[{"content":"You have just learned that you have RET fusion lung cancer. Or that someone you love has received this diagnosis.\nI know what you are going through. I have been there.\nThe first reaction is to feel like the world has stopped. Then comes the need to do something \u0026ndash; anything \u0026ndash; immediately. But here is what I have learned: the most important thing you can do right now is understand what you have, what options exist, and how to avoid the mistakes that can cost you.\nThis guide gives you everything you need to know \u0026ndash; from diagnosis to treatment, from side effects to emergencies, from what lies ahead to how you live day to day with this diagnosis. It is the map I wish I had.\nThe good news, before anything else: Your cancer has an approved, targeted treatment that works. You are not stuck with generic chemotherapy. Read on.\nWhat you have \u0026ndash; understanding the diagnosis You have a rare subtype of non-small cell lung cancer (NSCLC) driven by a RET gene fusion. Two genes in your tumor cells have joined together, creating an abnormal protein that tells cells to grow without stopping. The good news: this fusion is targetable \u0026ndash; there is a precision drug designed specifically for it.\nWhat RET fusion means Your cancer cells carry a specific genetic alteration: the RET gene has fused with another gene (most commonly KIF5B or CCDC6, though other partners exist). This fusion creates a signaling protein \u0026ldquo;stuck on\u0026rdquo; that drives cancer growth. Selpercatinib (Retevmo) directly blocks this abnormal RET protein.\nThe fusion partner matters:\nRET Partner What it means Clinical notes KIF5B-RET Most common (over 50% of cases) May show higher initial resistance; responds well to selective RET inhibitors CCDC6-RET Second most common Generally more responsive; excellent response to Selpercatinib Others (NCOA4, TRIM33 etc.) Rare variants All respond to RET-specific inhibitors Ask your doctor: \u0026ldquo;What RET fusion partner do I have?\u0026rdquo; The answer influences prognosis and treatment decisions if resistance develops.\nHow the diagnosis was confirmed The RET fusion was identified through molecular testing \u0026ndash; a genetic analysis of your tumor. Selpercatinib must be given only to patients with confirmed RET fusions.\nTesting method What it does Accuracy NGS (Next-Generation Sequencing) Reads the tumor DNA/RNA to find RET and other mutations simultaneously Over 95% \u0026ndash; gold standard FISH Uses fluorescent probes to visualize RET breakpoints 90-95% sensitivity, but lower specificity RT-PCR Detects RET fusion mRNA transcripts High for common partners Warning If you only had FISH, without NGS: Request confirmation by NGS. FISH can produce false-positive results and does not identify the exact fusion partner. NGS also detects co-mutations that influence prognosis. Who gets RET fusion lung cancer This type of cancer has a distinct patient profile:\nAge: Younger patients (median 55-62 years) Smoking: 55-70% are never-smokers or light smokers Sex: More common in women (60-70%) Histology: 99%+ are adenocarcinomas Important: RET fusions occur alone \u0026ndash; they do not usually coexist with EGFR, ALK, or ROS1 Your cancer is NOT caused by smoking. It is a spontaneous genetic accident in the tumor cells, not in your inherited genes. If you are at the beginning of your journey, also read the complete oncology diagnosis guide \u0026ndash; it covers the correct order of steps, from PET-CT to molecular testing.\nPrognosis: the real numbers Without RET-targeted therapy (older data): Median survival of 8-12 months with standard chemotherapy.\nWith Selpercatinib (current treatment):\nOverall response rate (ORR): 84% in patients who receive it as first-line treatment Progression-free survival (PFS): 24.8 months \u0026ndash; most patients remained stable on treatment for nearly two years Disease control rate: 88% Overall survival (OS): Not yet reached after 3.5+ years in first-line treated patients Brain metastases are common: 46% of RET fusion patients develop brain tumors during their lifetime. Regular brain MRI is essential.\nThe number that truly matters: Your individual prognosis depends on stage, fusion partner, co-mutations (such as TP53), and how your specific tumor responds to Selpercatinib. Ask your oncologist for YOUR NUMBERS.\nCo-mutations to check for Co-mutation Frequency Clinical impact TP53 ~45-50% Associated with worse prognosis and higher metastatic burden PIK3CA / PTEN loss ~25-30% May drive resistance; suggests need for combination therapies KRAS Under 10% Rare, as RET and KRAS are usually mutually exclusive Ask your doctor: \u0026ldquo;Does my tumor have co-mutations besides RET? Especially TP53 or PIK3CA?\u0026rdquo;\nThe best treatment right now Selpercatinib (Retevmo) \u0026ndash; the standard first-line treatment Selpercatinib is the preferred selective RET inhibitor for RET fusion lung cancer. Here is why:\nDoubles PFS compared to chemotherapy + pembrolizumab: 24.8 months vs. 11.2 months Superior response rate: 84% tumor reduction in first-line treated patients Brain penetration: 91% intracranial response rate in patients with brain metastases at baseline Selective for RET \u0026ndash; fewer side effects than older multi-kinase inhibitors Why immunotherapy does NOT work in RET-fused cancer Approach Response rate Selpercatinib alone 84% Chemotherapy + pembrolizumab 56% Immunotherapy alone in RET+ patients Poor Why? RET fusion-positive tumors have \u0026ldquo;cold\u0026rdquo; immune microenvironments with low PD-L1 expression. Immunotherapy targets the PD-1/PD-L1 axis \u0026ndash; your cancer does not depend on this checkpoint.\nLIBRETTO-431 explicitly showed: Pembrolizumab added to chemotherapy did not improve outcomes compared to chemotherapy alone in RET+ patients, and both were inferior to Selpercatinib.\nImportant Do NOT accept immunotherapy alone for RET-fused lung cancer. The international standard of care is Selpercatinib, not pembrolizumab or nivolumab. Selpercatinib vs. Pralsetinib (Gavreto) Factor Selpercatinib Pralsetinib ORR (first-line) 84% 61% PFS (first-line) 24.8 months 16.5-17 months Brain activity 91% intracranial response ~56% intracranial response Dosing 120-160 mg twice daily 400 mg once daily (on empty stomach) Guideline preference Preferred first-line Alternative Important for Romania and the EU: Pralsetinib (Gavreto) was withdrawn from the EU in October 2024 \u0026ndash; not for safety reasons, but through a commercial decision by the manufacturer. Selpercatinib is the only targeted RET inhibitor available in Europe.\nWhat NOT to do \u0026ndash; mistakes that can cost you If you are on Selpercatinib, the decisions you make outside the clinic matter just as much as those inside it. Some mistakes are easy to make \u0026ndash; a glass of juice, a vitamin, a supplement recommended by a neighbor. All of them can cost you.\nRead this section carefully. Print it. Show it to your family.\nMISTAKE 1: Grapefruit juice What happens: Grapefruit inhibits CYP3A4, the liver enzyme that breaks down Selpercatinib. When CYP3A4 is blocked, Selpercatinib accumulates in the blood at dangerously high concentrations. A single glass of grapefruit juice is enough to cause harm.\nInstead: Completely eliminate grapefruit, grapefruit juice, and products containing grapefruit for the entire duration of treatment. Oranges, apples, and lemons are safe.\nMISTAKE 2: St. John\u0026rsquo;s Wort What happens: St. John\u0026rsquo;s Wort does the opposite of grapefruit \u0026ndash; it speeds up CYP3A4, dramatically reducing the amount of drug in your blood. Less drug = treatment stops working. The tumor may progress silently.\nInstead: Do NOT take St. John\u0026rsquo;s Wort in any form during treatment. If you have depression or fatigue, tell your oncologist \u0026ndash; there are options that do not interact with your treatment.\nMISTAKE 3: Antibiotics without telling your oncologist What happens: Clarithromycin (Biaxin/Klacid) is a strong CYP3A4 inhibitor. Like grapefruit, it can make your Selpercatinib level rise dangerously in the blood.\nInstead: Tell every doctor who prescribes you anything: \u0026ldquo;I am on Selpercatinib \u0026ndash; a CYP3A4 substrate.\u0026rdquo; If you are prescribed clarithromycin, ask for alternatives (azithromycin, amoxicillin) \u0026ndash; discuss with your oncologist first.\nMISTAKE 4: High-dose antioxidant supplements What happens: Research shows that antioxidant supplements (vitamin A, C, E, coenzyme Q10) taken during treatment can protect cancer cells from the effects of therapy, reducing treatment effectiveness.\nInstead: Get nutrients from food, not from megadose pills. Bring a complete list of every supplement to every appointment. \u0026ldquo;Natural\u0026rdquo; does not mean safe during cancer treatment.\nMISTAKE 5: Stopping Selpercatinib because you feel better What happens: RET inhibitors are not cures \u0026ndash; they continuously suppress tumor growth. Stopping allows residual cancer cells to resume proliferating. Underdosing can allow resistant clones to emerge.\nInstead: Side effects, even severe ones, usually have manageable solutions. If they become unbearable, call your oncologist the same day \u0026ndash; do not stop treatment on your own.\nMISTAKE 6: Replacing treatment with alternative medicine What happens: RET fusion-positive lung cancer has a specific, targetable molecular driver. No alternative remedy targets RET fusions. Delaying effective therapy allows cancer to progress to a point where subsequent treatment becomes less effective or impossible.\nInstead: Complementary approaches (nutrition, exercise) can support treatment \u0026ndash; they do not replace it. If you are considering cannabis-based products, tell your oncologist \u0026ndash; some can interact with CYP3A4 pathways.\nMISTAKE 7: Ignoring new respiratory symptoms What happens: Selpercatinib can cause interstitial pneumonitis (severe lung inflammation) \u0026ndash; a serious, potentially life-threatening complication documented in RET+ lung cancer patients.\nInstead: Call your oncology team immediately if you experience: new or worsening shortness of breath, persistent dry cough, chest discomfort, fever with respiratory symptoms. Do NOT wait for your next appointment.\nMISTAKE 8: Assuming your psychiatrist or GP knows the interactions What happens: Selpercatinib is a moderate CYP3A4 inhibitor \u0026ndash; it can affect the metabolism of other medications (including psychiatric ones). The interaction goes both ways.\nInstead: Give every doctor, every dentist, and every pharmacist the complete list of your oncology medications. Do not assume specialists communicate with each other \u0026ndash; they often do not.\nQuick reference: substances to avoid on Selpercatinib Substance Risk Grapefruit / grapefruit juice CYP3A4 inhibition \u0026ndash; toxic accumulation St. John\u0026rsquo;s Wort CYP3A4 induction \u0026ndash; treatment fails Clarithromycin (Biaxin/Klacid) Strong CYP3A4 inhibitor \u0026ndash; toxic accumulation Kaletra (lopinavir/ritonavir) Strong CYP3A4 inhibitor High-dose antioxidants (A, C, E, CoQ10) May protect cancer cells High-dose vitamin B12 Associated with increased recurrence risk Any unreviewed supplement Unknown interactions \u0026ndash; treat as unsafe How to take your treatment correctly Selpercatinib (Retevmo) dosing Your weight Standard dose Under 50 kg 120 mg orally twice daily (every 12 hours) 50 kg or more 160 mg orally twice daily (every 12 hours) Take the pills at the same times every day. Set phone alarms \u0026ndash; consistency prevents drug level drops.\nCritical rules for stomach acid and food Selpercatinib has pH-dependent solubility: it dissolves well in acid and becomes practically insoluble at neutral pH. Anything that raises stomach pH reduces how much drug reaches the blood.\nYour situation What to do Why You take a PPI (omeprazole, lansoprazole, pantoprazole) You MUST take Selpercatinib WITH FOOD PPIs reduce absorption by -69% (total drug in blood) and -88% (peak level) when taken on an empty stomach You take an H2 blocker (famotidine/Pepcid) Take Selpercatinib 2 hours BEFORE or 10 hours AFTER the H2 blocker H2 blockers also raise pH You take antacids (Tums, Rennie, Maalox) Separate by at least 2 hours Same pH problem Dairy products (milk, yogurt, cheese) Avoid 2 hours before and 2 hours after Selpercatinib dose Calcium in dairy buffers stomach acid Water: Take Selpercatinib with ~200 ml (a small cup) of water. Avoid drinking a full glass (over 400 ml) at the same time \u0026ndash; large amounts of water dilute stomach acid.\nIf you missed a dose Remembered within a few hours? Take it immediately, then resume your normal schedule It is nearly time for the next dose? Skip the missed dose. Do NOT take a double dose Not sure? Call your pharmacist or oncology nurse If you vomited after a dose Do NOT retake the dose. Your stomach has already absorbed most of it. Resume your normal schedule at the next planned time.\nSide effects \u0026ndash; real probabilities This section shows you what actually happens to patients on Selpercatinib. Real numbers, not vague phrases.\nThe honest picture: In a real-world study of 243 patients, 86% had at least one adverse event and 48% had a severe one (Grade 3+). But this does NOT mean treatment is intolerable \u0026ndash; most patients report stable or improved quality of life.\nWhat will PROBABLY happen (over 50% of patients) Side effect How common What it means What to do Elevated liver enzymes (AST) 59% You feel nothing \u0026ndash; it shows up in blood tests. 3% have serious liver damage. Blood tests every 2 weeks x 3 months, then monthly Elevated blood sugar 53% You may not notice initially. 2.8% have severe elevation. Baseline glucose + periodic monitoring Edema (face/leg swelling) 49% Can limit daily function in severe cases Elevate limbs; diuretics if needed Fatigue 46% Not normal tiredness \u0026ndash; a profound exhaustion. The most impactful daily side effect. Aerobic exercise 3 times per week \u0026ndash; proven to help Dry mouth Very common Persistent. Affects eating, speaking. Frequent sips of water; sugar-free gum Common and manageable Side effect Frequency (Grade 3+) What to do Hypertension 19.7% Grade 3+ Check before starting and regularly. Manageable with medication Elevated ALT (liver enzyme) 11.8% Grade 3+ Blood tests every 2 weeks x 3 months, then monthly Hyponatremia (low sodium) 9.2% Grade 3+ Routine electrolyte panel Diarrhea / constipation Very common BRAT diet; loperamide; hydration Nausea Common Small frequent meals; anti-nausea medication available Skin rash Common Moisturizer; topical steroids Elevated creatinine ~18% Usually a false alarm called pseudo-AKI \u0026ndash; selpercatinib blocks MATE transporters in the kidney, artificially raising creatinine without actual damage. To distinguish real from false: ask for cystatin C and electrolytes (sodium, magnesium, calcium) at every blood draw. If creatinine is up but cystatin C is normal and electrolytes are stable: continue full dose. If cystatin C is also elevated or electrolytes are dropping: contact oncologist immediately Rarer but DANGEROUS \u0026ndash; attention saves lives here Side effect Frequency What to watch for What to do QTc prolongation (heart rhythm) 33% some degree; 5% life-threatening Chest pain, fainting, palpitations ECG before starting + regular monitoring Severe liver injury 3% Yellowing skin/eyes, dark urine, right upper abdominal pain Blood tests every 2 weeks x 3 months Pneumonitis (lung inflammation) 4% but can be fatal New/worsening shortness of breath, cough, chest discomfort Emergency IMMEDIATELY. No \u0026ldquo;wait and see\u0026rdquo; Severe hemorrhage 2.3% serious Unusual bleeding from anywhere Stop the drug; call emergency services if you have neurological symptoms or cough up blood Tumor lysis syndrome Early in treatment Severe fatigue, cramps, dark urine, nausea Emergency \u0026ndash; especially in the first weeks Hypersensitivity reaction 4.3% Fever + rash + joint pain + low platelets Stop Selpercatinib immediately Newly identified risks (real-world data, December 2024) Side effects not previously on the label, found through pharmacovigilance and real-world studies:\nDysphagia \u0026ndash; difficulty swallowing. Report to oncologist if new or worsening Pericardial effusion \u0026ndash; fluid around the heart (chest pressure, shortness of breath when lying down). Baseline echocardiogram recommended, repeat every 6 months or at symptom onset Hemiparesis \u0026ndash; weakness on one side of the body (stroke-like). Requires urgent brain MRI to differentiate from brain metastases Intestinal lymphangiectasia \u0026ndash; protein-losing enteropathy found in up to 29% of patients (TTLC 2026, MSKCC). Causes chronic diarrhea, malabsorption, and low albumin. Manageable with low-fat MCT diet and dose adjustment. Monitor albumin at every blood draw Thyroid function \u0026ndash; the forgotten check Selpercatinib inhibits DIO2, the enzyme that converts T4 (inactive thyroid hormone) to T3 (the active form). Approximately 13% of patients develop clinical hypothyroidism \u0026ndash; which causes fatigue, weight gain, and fluid retention that can be confused with other side effects.\nThe fix is simple: levothyroxine, a cheap medication with zero CYP3A4 interaction. But it only works if the problem is detected.\nAsk your oncologist to add TSH + free T4 to every blood draw. If TSH rises above 4.5 or free T4 drops below normal, levothyroxine should be started.\nHow side effects evolve over time The side effect profile of selpercatinib changes significantly over 6-24 months. What bothers you at month 2 is not the same as what bothers you at month 18:\nSide effect Early (months 1-6) Late (24+ months) Why it changes Edema 27.5% 63.2% Cumulative VEGFR inhibition impairs lymphatic drainage Diarrhea 30.5% 60.7% Intestinal lymphangiectasia develops gradually (median onset 15 months) Fatigue 36.6% 53.0% Multifactorial (metabolic, hypothyroidism, anemia) Liver enzymes (ALT) 30.5% 15.8% Liver adapts over time \u0026ndash; good news This is important to know because:\nIt is manageable \u0026ndash; only 2% of patients discontinue selpercatinib due to side effects Preparation helps \u0026ndash; compression stockings, loperamide supply, MCT diet knowledge, thyroid monitoring Dose adjustment works \u0026ndash; late side effects respond to dose reduction without necessarily losing efficacy Tip Proactive steps starting month 6: Begin wearing compression stockings for edema prevention. Ensure albumin is tested monthly to detect protein loss early. Have loperamide available. Continue TSH monitoring at every blood draw. Drug and food interactions Selpercatinib is primarily metabolized by CYP3A4 and CYP2C8 enzymes in the liver. Think of these enzymes as \u0026ldquo;chemical scissors.\u0026rdquo; If something blocks the scissors, the drug level rises. If something sharpens them, the drug level drops.\nSubstances that INCREASE Selpercatinib levels (DANGER) Substance Type What to do Grapefruit / Seville oranges Fruit AVOID COMPLETELY Itraconazole, ketoconazole, voriconazole Antifungals AVOID if possible. If necessary, Selpercatinib dose is reduced + more frequent ECGs Ritonavir, lopinavir HIV medications AVOID. Discuss alternatives Erythromycin, clarithromycin Macrolide antibiotics Ask for azithromycin instead Cyclosporine, tacrolimus Immunosuppressants Inform your transplant team If you MUST take a strong CYP3A4 inhibitor, your Selpercatinib dose may be reduced to 80 mg twice daily, with more frequent cardiac monitoring.\nSubstances that REDUCE effectiveness (treatment stops working) Substance Type What to do St. John\u0026rsquo;s Wort Herbal supplement DO NOT USE \u0026ndash; EVER Carbamazepine (Tegretol) Anticonvulsant CONTRAINDICATED Phenytoin (Dilantin) Anticonvulsant CONTRAINDICATED Rifampicin Antibiotic (TB) CONTRAINDICATED \u0026ndash; reduces Selpercatinib levels by half Other foods and substances that may affect Selpercatinib Food / substance Potential effect Action Black seed oil (Nigella sativa) May inhibit CYP3A4 and CYP2C8 \u0026ndash; risk of increased Selpercatinib levels Avoid during treatment Turmeric / curcumin in large doses CYP3A4 and CYP2C8 inhibitor Small amounts in food OK; concentrated supplements \u0026ndash; avoid Green tea (concentrated extract) May affect CYP450 enzymes Occasional tea OK; extract supplements \u0026ndash; discuss with oncologist Garlic (supplements or large amounts) May affect CYP3A4 metabolism Small amounts in cooking OK; garlic supplements \u0026ndash; avoid Red wine CYP3A4 effect + combined liver stress Avoid Alcohol Additional liver stress on a drug that affects the liver in 59% of patients Minimize or avoid completely Tip Check any food or supplement before consuming it. You can use an AI tool (such as ChatGPT, Claude, or Gemini) to quickly check the interaction between Selpercatinib and any ingredient or food. Ask: \u0026ldquo;Does [food/supplement name] interact with Selpercatinib (RET inhibitor, CYP3A4/CYP2C8 substrate)?\u0026rdquo; This does not replace medical advice, but can help you identify potential risks to discuss with your oncology team. Interaction checklist \u0026ndash; print and bring to every pharmacy Tell the pharmacist: \u0026ldquo;I am on Selpercatinib (RETEVMO) for lung cancer\u0026rdquo; Ask: \u0026ldquo;Does this new medication inhibit or induce CYP3A4?\u0026rdquo; Ask: \u0026ldquo;Does it interact with Selpercatinib?\u0026rdquo; Ask: \u0026ldquo;Can it affect heart rhythm or blood pressure?\u0026rdquo; What monitoring you need Monitoring is not optional \u0026ndash; it is an essential part of treatment that keeps you alive and catches problems early.\nBaseline tests BEFORE the first dose Test Why now Complete metabolic panel Kidneys, liver, electrolytes \u0026ndash; baseline Liver function (ALT, AST, bilirubin) Selpercatinib can affect the liver; you need a baseline ECG (12-lead) Selpercatinib prolongs QTc in ~33% of patients Blood pressure Selpercatinib causes hypertension in ~14-20% Fasting glucose or HbA1c 53% develop hyperglycemia TSH (thyroid hormone) Baseline for detecting future hypothyroidism Calcium and Vitamin D Essential, especially if you will be on Xgeva Pregnancy test (if applicable) Selpercatinib is teratogenic \u0026ndash; it causes birth defects Schedule: what tests, when Test Months 1-3 Month 4+ Liver function Every 2 weeks Monthly Blood pressure Week 1, then weekly x 8 weeks Monthly ECG Baseline, at 1-2 weeks and 4 weeks If palpitations, dizziness, new dose Electrolytes Every 2 weeks Monthly Kidney function Monthly Every 3 months Blood sugar Baseline done Every 3-6 months TSH Baseline done Every 6-12 months Imaging (CT chest/abdomen) Baseline; repeat at ~8 weeks Every 8-12 weeks Brain MRI \u0026ndash; do NOT wait for headaches 46% of RET fusion patients develop brain metastases. Many are asymptomatic initially.\nTiming Recommendation At diagnosis Brain MRI with contrast (standard of care) First year Every 8-12 weeks initially After stable response Every 3-6 months New neurological symptoms Urgent brain MRI, regardless of schedule If your doctor says \u0026ldquo;we will scan if you have symptoms,\u0026rdquo; push back \u0026ndash; surveillance scanning is the standard of care for RET fusion lung cancer.\nHow to interpret liver tests ALT elevation What it means Action Under 3x normal Mild; expected Continue Selpercatinib; repeat in one week 3-5x normal Moderate Reduce Selpercatinib dose or temporarily hold; repeat in 1 week Over 5x normal with symptoms Severe hepatotoxicity Stop Selpercatinib immediately. Contact your oncologist the same day When to go to the emergency room \u0026ndash; NOW PRINT THIS PAGE. PUT IT ON YOUR FRIDGE. CARRY IT IN YOUR WALLET. GIVE A COPY TO YOUR PARTNER/FAMILY.\nEMERGENCY CHECKLIST \u0026ndash; Go to the emergency room if you have any of these: Warning New or worsening shortness of breath + dry cough + fever \u0026ndash; Call emergency services / Go to the ER IMMEDIATELY. This triad is the warning sign for drug-induced pneumonitis. Do NOT take your next dose until a doctor evaluates you. Warning Coughing up blood OR unexplained bleeding that will not stop \u0026ndash; Call emergency services IMMEDIATELY. Hemorrhagic events are documented with Selpercatinib, including cerebral and respiratory bleeding. Warning Yellowing of skin/eyes + dark urine + right upper abdominal pain \u0026ndash; Go to the ER THE SAME DAY. Classic signs of severe hepatotoxicity. Stop Selpercatinib and go straight to the ER. Warning Chest pain + palpitations + fainting or near-fainting \u0026ndash; Call emergency services IMMEDIATELY. Selpercatinib causes QTc prolongation \u0026ndash; a dangerous change in heart rhythm. Tell the ER that you are on Selpercatinib \u0026ndash; they will do an ECG immediately. Warning Sudden weakness on one side of the body + severe headache + confusion \u0026ndash; Call emergency services IMMEDIATELY. Signs of cerebral hemorrhage or stroke. Warning Chest pressure + difficulty breathing when lying down \u0026ndash; Go to the ER THE SAME DAY. Suspect pericardial effusion (fluid around the heart). Warning Severe fatigue + muscle cramps + dark urine + nausea (especially in the first weeks) \u0026ndash; Go to the ER / Call the oncology hotline IMMEDIATELY. Suspect tumor lysis syndrome. Warning Fever above 38.5C + chills + rapid heart rate + no obvious cause \u0026ndash; Call the oncology hotline IMMEDIATELY. If no response within 15 minutes \u0026ndash; go to the ER. Fever in a cancer patient on targeted therapy is a medical emergency until proven otherwise. What to bring to the emergency room \u0026ndash; every time What Why Complete medication list (including dose and time) Selpercatinib has 664 documented interactions \u0026ndash; ER staff need to know before giving you anything Selpercatinib bottles Confirm the drug, dose, lot Latest blood test results Give the ER a comparison baseline Oncologist\u0026rsquo;s name and phone number The ER should contact them before major decisions This checklist So the ER staff understand you are on a RET inhibitor Do NOT take your next dose if you are in the ER for any of the situations above.\nSerious but NOT immediately life-threatening \u0026ndash; call your oncologist TODAY Blood pressure above 140/90 mmHg on two separate readings Unexplained weight gain of over 2 kg in 3 days (possible edema) Persistent nausea and vomiting preventing you from taking Selpercatinib New hyperglycemia symptoms (extreme thirst, frequent urination, blurred vision) Any new neurological symptoms Where it spreads and what to do Brain metastases \u0026ndash; complication number 1 Nearly 50% of RET fusion patients will develop brain metastases during their lifetime. This is not a rare event \u0026ndash; it is the most common complication.\nDoes Selpercatinib work in the brain? Yes. 82% brain response rate in the LIBRETTO-431 trial. Selpercatinib can also prevent the development of new brain metastases.\nIf brain metastases develop despite Selpercatinib:\nTreatment What it is When it is used Stereotactic radiosurgery (SRS) Focused radiation beam aimed at the brain tumor. 1-5 sessions. Outpatient. If you have 1-4 brain metastases. Can be combined with Selpercatinib. Continue Selpercatinib alone If lesions are small (under 5 mm) or asymptomatic Requires close follow-up imaging (at 4-6 weeks) Bone metastases Bone is a common site of metastasis. If you have unexplained bone pain, report it immediately \u0026ndash; do not assume it is arthritis or aging.\nBone pain: Radiation to the painful site + pain medication Fracture risk: Denosumab (Xgeva) or bisphosphonates to strengthen the bone Spinal metastases: If you develop back pain + weakness/numbness in the legs, go to the ER immediately \u0026ndash; risk of spinal cord compression Denosumab (Xgeva) protocol for bone metastases If you have bone metastases, Xgeva (denosumab) is recommended to prevent complications (fractures, spinal cord compression).\nAdministration: 120 mg subcutaneous injection every 28 days Vitamin D: Minimum 400 IU daily Calcium: Minimum 600 mg daily \u0026ndash; preferably calcium citrate (better absorption) CRITICAL: Take calcium supplements at least 2 hours BEFORE OR 2 hours AFTER Selpercatinib Practical example: Selpercatinib at 8:00 AM and 8:00 PM. Calcium + Vitamin D at noon Dental warning: Tell your dentist you are on Xgeva before any dental procedure Oligometastatic management \u0026ndash; the key concept If you have a limited number of metastases (1-5 sites), the most effective strategy may be local treatment of resistant lesions (radiation, ablation) while continuing Selpercatinib \u0026ndash; not changing the entire treatment plan.\nThe logic: if most of your cancer responds to Selpercatinib but 1-2 sites are growing, those sites may have local resistance. Destroying them eliminates the resistant cells while Selpercatinib continues to control the rest.\nAsk your oncologist: \u0026ldquo;Do I have oligometastatic disease? Would SBRT or ablation be appropriate for some lesions, while continuing Selpercatinib?\u0026rdquo;\nWhen treatment stops working The difficult truth: virtually every patient on Selpercatinib will eventually develop resistance. The question is not \u0026ldquo;if\u0026rdquo; \u0026ndash; but \u0026ldquo;when,\u0026rdquo; \u0026ldquo;how,\u0026rdquo; and \u0026ldquo;what do you do next.\u0026rdquo; You need a plan BEFORE you need it.\nTwo families of resistance Category What it means How common On-target (RET-dependent) The cancer mutates the RET gene itself (G810, V804M, Y806C mutations) ~12.4% of biopsies at progression Off-target (bypass) The cancer activates an entirely different survival pathway (MET amplification, KRAS, EGFR) The majority of resistance cases What to request at progression Do not accept \u0026ldquo;the cancer is growing\u0026rdquo; as a complete answer. Demand to know WHY.\nLiquid biopsy (ctDNA) \u0026ndash; a blood test that detects resistance mutations months before scans show tumor growth Tissue re-biopsy \u0026ndash; if liquid biopsy is negative but progression is clear Full NGS \u0026ndash; mandatory with every re-biopsy Your resistance strategy: three levels LEVEL 1 \u0026ndash; Options available NOW:\nStrategy When Continue Selpercatinib beyond progression (oligoprogression) If progression is limited to 1-3 sites. Add local treatment (SBRT). Additional median benefit: 9.8 months Pralsetinib (Gavreto) If resistance is off-target. Limited access in the EU after October 2024 withdrawal Chemotherapy (pemetrexed-based) Standard fallback. Often a bridge between first and next-generation RET inhibitors Selpercatinib rechallenge Documented in 2026: reintroduction after a chemotherapy interval produced near-complete brain remission LEVEL 2 \u0026ndash; Next-generation RET inhibitors (in clinical trials NOW):\nDrug What it does Status EP0031 (Lunbotinib) Selective RET inhibitor; broad activity vs. solvent front mutations Phase 1-2, ASCO 2025 data LOXO-260 Targets solvent front and gatekeeper mutations Phase 1; estimated completion June 2026. No expanded access program currently available Vepafestinib Selective RET; improved brain penetration Phase 1-2; MARGARET trial SY-5007 Selective RET inhibitor; 62% response rate Phase 2-3 (China) LEVEL 3 \u0026ndash; Targeted combinations (based on YOUR resistance mechanism):\nBypass identified Combination strategy MET amplification Selpercatinib + crizotinib (MET inhibitor) \u0026ndash; 4 documented cases with response EGFR/HER3 activation Discuss with oncologist \u0026ndash; preclinical data exists (afatinib) but clinical adoption is limited due to toxicity concerns BRAF fusion RET inhibitor + MEK inhibitor \u0026ndash; 1 documented case of success Expert centers that think ahead Center Why it matters Memorial Sloan Kettering (NYC) Alexander Drilon \u0026ndash; world\u0026rsquo;s number 1 for RET tumors. Serial liquid biopsies, resistance profiling, personalized combinations MD Anderson (Houston) Vivek Subbiah \u0026ndash; RET research, off-label combinations Gustave Roussy (Paris) Largest cancer center in Europe. Active clinical trials with next-generation RET inhibitors. The most accessible major EU center for Romanian patients IRCCS Milan Real-world experience with RET+ NSCLC in the European context Ask your oncologist: \u0026ldquo;Can you refer me to one of the centers above for a second opinion or trial enrollment?\u0026rdquo;\nWhat lies ahead \u0026ndash; pipeline and clinical trials Frontier technologies (2-5+ years away, but real science) Histotripsy \u0026ndash; Focused ultrasound waves destroy tumors without surgery, without radiation. FDA-approved for liver tumors (2023). Relevant if you develop liver metastases.\nLungVax vaccine (Oxford/UCL) \u0026ndash; The first preventive lung cancer vaccine. Trains the immune system to recognize \u0026ldquo;alarm signal\u0026rdquo; proteins on abnormal lung cells. Phase I from summer 2026. Relevant if you achieve remission and worry about recurrence.\nPROTACs \u0026ndash; Instead of blocking the RET protein (as Selpercatinib does), they destroy the RET protein completely through the cell\u0026rsquo;s own disposal system. You cannot develop binding-site resistance if the entire protein is destroyed. 3-5 years from patients.\nANKTIVA + Keytruda \u0026ndash; IL-15 grows new T cells and NK cells; Keytruda unblocks them. Conditional EU authorization (February 2026). Phase 3 trial for NSCLC (ResQ201A) currently enrolling.\nmRNA cancer vaccines \u0026ndash; BNT116 (BioNTech): FDA filing 2025 for NSCLC. Over 120 mRNA oncology vaccine clinical trials underway.\nHow to find and enroll in a clinical trial ClinicalTrials.gov \u0026ndash; search \u0026ldquo;RET fusion NSCLC\u0026rdquo; for open trials LUNGevity Foundation \u0026ndash; LungMATCH navigator The Happy Lungs Project (happylungsproject.org) \u0026ndash; tracks RET-specific trials RETpositive.org \u0026ndash; clinical trial database and community Compassionate / expanded access: ask your oncologist if LOXO-260 or other experimental drugs are available outside of trials In Romania/EU: cross-border enrollment in an EU clinical trial is possible Day-to-day life on Selpercatinib Realistic treatment timeline Weeks 1-2: Nausea, appetite loss, fatigue, dry mouth. Establish your dosing routine. Highest risk of tumor lysis syndrome.\nMonths 1-3: Side effects declare themselves. Fatigue may deepen. Blood pressure may start to rise. Highest risk of hepatotoxicity \u0026ndash; blood tests every 2 weeks. 31% of patients need a dose reduction.\nMonths 3-12: If you have tolerated it this far, acute risks decrease (but do not disappear). The first scans will likely show response. Exercise and nutrition become critical.\nYear 1-2: Most patients still respond (median PFS ~24.8 months). Start discussing with your doctor: what is the plan if resistance develops?\nYear 2+: Statistically, roughly half of patients will see progression. Some continue to respond much longer.\nExercise \u0026ndash; the most supported non-drug intervention What works: Aerobic + resistance training combined.\nHow often: 3 times per week. Programs under 12 weeks show the strongest fatigue reduction.\nStart with: Walking. Even 10-15 minutes. Increase gradually.\nThe trap: Fatigue makes you want to rest. Resting makes fatigue worse. Movement breaks the cycle.\nStrategy How often Aerobic exercise 3-5 days/week, 30-45 min Resistance training 2-3 days/week, light weights Protein intake 1.2-1.5 g/kg body weight daily Anti-inflammatory diet Daily: vegetables, fish, olive oil Hydration 2-3 liters/day minimum Eating during treatment Small, frequent meals \u0026ndash; 5-6 per day instead of 3.\nProtein-rich foods \u0026ndash; protect against muscle wasting.\nFruits and vegetables: 5-6 servings per day. Antioxidants from food are OK; antioxidant supplements are NOT.\nWhen food tastes wrong: Cold foods (less smell), experiment with seasonings.\nRequest a referral to an oncology dietitian \u0026ndash; this is treatment support, not wellness advice.\nMental health Anxiety, depression, and adjustment disorders are common and predictable responses to diagnosis and ongoing treatment. This is not weakness.\nSeek psychological support proactively \u0026ndash; do not wait until you are in crisis:\nCounseling or therapy (individual, group, or couples) Support groups for lung cancer patients Financial counseling if treatment costs are a burden Fertility Selpercatinib is teratogenic (causes birth defects). Women must use effective contraception during treatment and for 1 week after stopping.\nIf you want children, discuss fertility preservation BEFORE continuing treatment. Freezing eggs or sperm before starting is an option.\nSurgery and travel Stop Selpercatinib at least 7 days before ANY surgery, including dental Travel: Carry Selpercatinib in the original bottles in your carry-on luggage. Carry a letter from your oncologist confirming the prescription Treatment access Romania \u0026ndash; FREE, but requires a legal procedure for first-line access Context: Selpercatinib was initially approved as a second-line treatment (after chemotherapy failure). In 2022 (FDA) and 2023 (EMA), it was updated to first-line treatment based on the LIBRETTO-431 results. Both ESMO and NCCN now recommend Selpercatinib as Category 1 first-line monotherapy.\nThe problem in Romania: CNAS (the national health insurance authority) has not updated its reimbursement guidelines. Selpercatinib is covered through standard channels only as a second-line treatment. Romanian patients are forced to undergo inferior chemotherapy first \u0026ndash; contradicting international guidelines \u0026ndash; unless they use the legal pathway below.\nHow to get free access to Selpercatinib in Romania Contact a lawyer experienced in medical law (a patient advocacy organization can recommend one) The lawyer files an \u0026ldquo;Ordonanta Presedintiala\u0026rdquo; (emergency court order) against CNAS The court file must include: A letter from your oncologist specifying Selpercatinib (Retevmo) as the recommended first-line treatment ESMO Clinical Practice Guidelines for metastatic NSCLC EMA Marketing Authorization for Retevmo Timeline: The court typically grants the order within 3-4 weeks Once approved, CNAS covers the full cost \u0026ndash; treatment is free for the patient Important Do NOT wait for CNAS to add Selpercatinib to the standard reimbursement list \u0026ndash; it could take years. The Ordonanta Presedintiala pathway is the established route that Romanian patients use for rare disease drugs not yet on the list. After the court approves your request Choose a pharmacy where you will pick up the medication from now on Your oncologist must write simple prescriptions (like antibiotic prescriptions) \u0026ndash; NOT electronic prescriptions with QR codes. QR prescriptions go through the standard CNAS system that does not cover first-line Selpercatinib. A simple prescription, backed by the court order, bypasses this limitation Contact the pharmacy at least 1 week before picking up the medication \u0026ndash; Selpercatinib is not routinely stocked and the pharmacy needs time to order it Keep copies of the court order with you at all times. The pharmacy will need to see it Be prepared: Even with the court order and full coverage, access can be unpredictable. The pharmacy may have supply delays, the prescription format may cause confusion for staff unfamiliar with the procedure. Patience and persistence are unfortunately part of treatment in Romania.\nAccess in other European countries Country Status France Approved and reimbursed; zero patient co-pay Germany Covered through statutory health insurance (GKV); positive G-BA assessment Italy Covered + mandatory RETSEVMO registry enrollment Spain Covered from April 2023 (after 840 days of waiting post-EMA approval) Poland Approved with restrictions; OncoMap precision medicine program underway UK Approved (restricted) through the Cancer Drugs Fund Manufacturer assistance programs (Eli Lilly) If you are uninsured or have high co-pays:\nContact: 1-844-RETEVMO (US) or the Eli Lilly support line in your country Offers: compassionate access, co-pay assistance, expanded access programs Processing in 2-3 weeks You are not alone RET-specific communities Resource What it offers RETpositive.org Private Facebook groups, clinical trial tracking, quality of life registries, patient stories The Happy Lungs Project RET-specific research updates, stories, webinars RET Renegades (Facebook) Support group co-founded by an 18+ year RET+ NSCLC survivor LUNGevity Foundation RET-specific support communities, LungMATCH navigator Cancer GRACE Forum for RET-fusion patients, treatment discussions Inspire Lung cancer survivor community and peer support forums HealthUnlocked GO2 for Lung Cancer community \u0026ndash; patient discussions and support Support for caregivers Your family members are affected too. Do not ask them to navigate this alone.\nLUNGevity Caregiver Support Groups \u0026ndash; online forums for families CancerCare Support Groups \u0026ndash; free support group for caregivers My Cancer Circle \u0026ndash; free online tool for organizing the care network American Lung Association Survivor Network \u0026ndash; peer support and shared experiences What to do now Print the \u0026ldquo;When to go to the emergency room\u0026rdquo; section and put it on your fridge and in your wallet Print the drug interaction list and show it to every doctor and pharmacist Ask your oncologist about the RET fusion partner, co-mutations, and brain MRI schedule \u0026ndash; also see the diagnosis guide for the correct order of investigations In Romania: Contact a lawyer for an Ordonanta Presedintiala if you need first-line access to Selpercatinib Sign up at RETpositive.org and The Happy Lungs Project \u0026ndash; find your community Discuss with your oncologist the action plan if resistance develops \u0026ndash; before you need it Request a liquid biopsy (ctDNA) for monitoring \u0026ndash; it can detect resistance months before scans show it Ready for more? Read Beyond Standard Treatment: A Proactive Strategy for RET Fusion Lung Cancer \u0026ndash; vaccines, cryoablation, ctDNA monitoring, and drug repurposing options The content of this article is for informational purposes only and does not constitute medical advice. Discuss any medical decision with your oncologist. If you have urgent symptoms, contact a doctor immediately. ","permalink":"https://oncoguide.github.io/en/cancer-types/lung-ret-fusion/","summary":"\u003cp\u003e\u003cstrong\u003eYou have just learned that you have RET fusion lung cancer. Or that someone you love has received this diagnosis.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eI know what you are going through. I have been there.\u003c/p\u003e\n\u003cp\u003eThe first reaction is to feel like the world has stopped. Then comes the need to do something \u0026ndash; anything \u0026ndash; immediately. But here is what I have learned: \u003cstrong\u003ethe most important thing you can do right now is understand what you have, what options exist, and how to avoid the mistakes that can cost you.\u003c/strong\u003e\u003c/p\u003e","title":"RET Fusion Lung Cancer: The Complete Patient Guide"},{"content":"You just found out you have cancer. Or that there is a serious suspicion. The world has stopped.\nI know what you are going through. I have been there.\nIn moments like these, the instinct is to do anything \u0026ndash;immediately. To accept the first plan someone proposes. To rush into treatment. But here is what I learned the hard way: the most important thing you can do right now is to reach a complete and accurate diagnosis before making any treatment decision.\nThis guide shows you exactly what steps to follow, in what order, and \u0026ndash;just as importantly \u0026ndash;what to avoid. It is the roadmap I wish I had.\nWhy the order of steps matters An oncology diagnosis is not a single test. It is a protocol \u0026ndash;a series of investigations that, done in the correct order, give you the full picture of your disease. Each step depends on the one before it.\nIn a specialized oncology center, this protocol can take 10 days. In a fragmented system, without coordination, it can take 8 weeks or more \u0026ndash;not because the tests themselves take longer, but because nobody is coordinating them efficiently.\nThe difference is not just about comfort. The difference can be between an optimal treatment and a suboptimal one. An incomplete diagnosis leads to incomplete decisions.\nStep 1: Whole-body PET-CT \u0026ndash;see the full picture FIRST The correct first step is to see the full extent of the disease. Not a simple CT, not an ultrasound. A whole-body PET-CT (from head to knee or below).\nWhat is PET-CT? PET-CT combines two technologies: PET (Positron Emission Tomography) shows metabolic activity \u0026ndash;meaning where cells are consuming energy more than normal (the sign of an active tumor). CT (Computed Tomography) shows anatomy \u0026ndash;the shape, size, and exact location.\nTogether, PET-CT shows you what is there and how active it is, across your entire body, in a single investigation.\nWhy PET-CT BEFORE biopsy? It shows whether the disease is localized or has spread (metastases) It guides the biopsy \u0026ndash; the doctor knows exactly where to sample, from the area with the strongest tumor activity. Without PET-CT, you risk the biopsy being taken from an inactive zone, and the result being inconclusive or inaccurate. It can completely change the approach: if metastases are present, the treatment plan is different PET-CT changes staging in 19-35% of cases compared to simple CT Warning DO NOT accept a biopsy without PET-CT. You need to know the extent of the disease before deciding where and how the biopsy is performed. In a specialized center, PET-CT is the first step. If your doctor suggests a biopsy without complete imaging, ask why. Equipment quality matters Not all PET-CTs are equal. State-of-the-art machines offer:\nLower radiation doses (important, especially if you will need multiple scans) Higher resolution \u0026ndash;detecting smaller lesions AI-assisted interpretation in some centers Ask what PET-CT model the center uses and when it was installed. Newer, latest-generation machines make a difference.\nStep 2: Biopsy \u0026ndash;the material everything is built on A biopsy is the procedure through which a piece of the tumor is collected to be analyzed under a microscope. Without a biopsy, there is no definitive diagnosis.\nTypes of biopsy Fine needle aspiration (FNA): Fast, minimally invasive. Used for thyroid, superficial lymph nodes. But it may collect too little material. Core needle biopsy: Collects a cylinder of tissue. Preferred for most solid tumors. Sensitivity 85-100%. CT-guided or ultrasound-guided biopsy: The needle is guided by imaging to the tumor. Essential for deep tumors (lung, liver, bone). Surgical biopsy: When other methods are not possible or sufficient. How long do results take? Basic histopathology report: 3-7 business days in a good center With immunohistochemistry (IHC): another 1-2 days In a specialized oncology center, the biopsy result can come in 3 days Ideally, choose a center that can guarantee fast turnaround times. If you are told the result takes 2-3 weeks, ask whether faster options exist \u0026ndash; including sending the sample to another lab or having it evaluated at a specialized center.\nWarning Insist on enough tissue. Tell the doctor performing the biopsy that you will need molecular/genetic testing (NGS). If too little material is collected, you may need to repeat the biopsy \u0026ndash;which means lost time and an additional procedure. Tip When scheduling your biopsy, ask: \u0026ldquo;Will enough material be collected for NGS molecular testing?\u0026rdquo; This needs to be planned from the start, not discovered later. Request fresh frozen tissue \u0026ndash;not just FFPE By default, your biopsy tissue will be preserved in formaldehyde and embedded in paraffin (called FFPE). This is standard and sufficient for most tests. But some advanced options \u0026ndash; cancer vaccines, organoid drug testing, high-quality RNA sequencing \u0026ndash; require fresh frozen tissue stored at -80 degrees Celsius.\nYou cannot go back and freeze tissue after it has already been fixed in formaldehyde. The decision must be made before the biopsy, not after.\nAsk the interventional radiologist or surgeon: \u0026ldquo;Can you also store some tissue cores fresh frozen at -80 degrees for future research and advanced testing?\u0026rdquo; If the center cannot do this, ask whether they can send cores to a biobank that can.\nIdeally, request 4-8 biopsy cores distributed between:\nPathology (diagnosis \u0026ndash; mandatory, always done) Molecular testing (NGS, WES, RNA-seq) Fresh frozen biobank at -80 degrees (for future options: vaccines, organoids, retesting) This one request, made at the right moment, can open treatment doors that do not yet exist today.\nStep 3: Molecular and genetic testing \u0026ndash;the most overlooked step This is probably the most important step that nobody talks about enough. Molecular tests analyze the DNA of your tumor and identify the specific mutations driving it. These mutations determine which treatment works and which does not.\nWhy does it change everything? Modern oncology has evolved enormously. Today there are targeted therapies \u0026ndash; drugs designed to specifically attack certain genetic mutations in your tumor. These treatments are often more effective and better tolerated than traditional chemotherapy.\nBut to receive the right treatment, you need to know what mutation you have.\nTwo patients with \u0026ldquo;lung cancer\u0026rdquo; can have completely different diseases at the molecular level. One has an EGFR mutation \u0026ndash; and there is a targeted drug that works remarkably well. The other has a KRAS G12C mutation \u0026ndash; and a different drug works. Without molecular testing, the doctor does not know which treatment is right for YOU.\nNot just for lung cancer This is a common misconception. Molecular testing is the standard of care (meaning mandatory according to international guidelines) for most advanced cancers:\nCancer type Mandatory tests (examples) Why it matters Lung (NSCLC) EGFR, ALK, ROS1, KRAS G12C, PD-L1 + others Over 10 targeted therapies available Breast ER, PR, HER2, BRCA1/2, PIK3CA Determines whether you receive hormonal therapy, anti-HER2 or PARP Colorectal KRAS/NRAS, BRAF, MSI/MMR Anti-EGFR is contraindicated in RAS-mutant Melanoma BRAF V600E, PD-L1 BRAF/MEK combination available only with BRAF mutation Ovarian BRCA1/2, HRD PARP inhibitors available for BRCA-mutant Prostate (metastatic) BRCA, HRR genes, MSI/MMR PARP inhibitors, immunotherapy Gastric HER2, PD-L1, MSI/MMR Trastuzumab, immunotherapy For a concrete example, read our complete guide to RET fusion-positive lung cancer \u0026ndash; a molecular subtype with a highly effective targeted treatment.\n\u0026ldquo;Agnostic\u0026rdquo; biomarkers \u0026ndash;valid for ANY cancer Regardless of your cancer type, there are biomarkers that can unlock treatment options for any solid tumor:\nMSI-H/dMMR \u0026ndash;responds to immunotherapy (pembrolizumab) NTRK fusions \u0026ndash;responds to larotrectinib or entrectinib TMB-H (high tumor mutational burden) \u0026ndash;responds to immunotherapy BRAF V600E \u0026ndash;combination dabrafenib + trametinib These should be tested regardless of what cancer you have.\nTwo types of tests: somatic and germline Somatic testing (of the tumor): Analyzes mutations acquired by your tumor. Done from biopsy tissue or from blood (liquid biopsy). Guides treatment. Germline testing (hereditary): Analyzes inherited mutations, present since birth. Done from a blood sample. Important for you AND for your family (cancer risk in relatives). They are not interchangeable. You may need both.\nHow long do they take? Rapid panel (subset of mutations): 3 days in specialized centers Full NGS panel: 7-14 days in a good lab Outsourced: can take 2-4 weeks Warning DO NOT start treatment without molecular testing results. A treatment chosen without this information may be ineffective or even counterproductive. The exception: medical emergencies where delaying treatment puts your life at risk. Warning DO NOT accept 21+ days of waiting for molecular testing without asking what faster options exist. Specialized centers get results in 3-10 days. If the local lab cannot deliver, ask about sending the sample to a faster lab or about liquid biopsy (from blood) as an alternative. Beyond standard panels: WES, WGS and RNA-seq A standard NGS panel tests 50-500 genes. This is usually sufficient \u0026ndash; but not always. For rare cancers, unusual molecular subtypes, or when the standard panel finds nothing actionable, more comprehensive options exist:\nWhole Exome Sequencing (WES): Tests all protein-coding genes (~20,000). Identifies co-mutations, neoantigen candidates for vaccines, and DNA repair defects (BRCA, FANCL, ATM) Whole Genome Sequencing (WGS): Tests the entire genome, including non-coding regions. The most comprehensive option \u0026ndash; 73-89% of patients receive actionable findings. Non-profit and academic programs exist in some EU countries: Hartwig Medical Foundation OncoAct (Netherlands, NSCLC explicitly covered) and NCT MASTER (Heidelberg, Germany \u0026ndash; WGS + RNA-seq + methylome). Access depends on your country \u0026ndash; these programs are typically reimbursed for patients in their home country\u0026rsquo;s healthcare system, but international patients usually need a cross-border referral, an S2 form (EU Cross-Border Healthcare Directive), or private payment. Ask your oncologist whether your country has a pathway to these programs or whether they accept international referrals RNA-seq: Shows which genes are actually active in your tumor. Can detect gene fusions, bypass resistance mechanisms, and transcriptional changes invisible to DNA-only testing These advanced tests are not always reimbursed by standard health insurance. Ask your oncologist whether they are covered or whether academic programs (often free) accept your case.\nStep 3b: AI-assisted pathology \u0026ndash;preserving precious tissue A new generation of AI tools can predict biomarkers directly from standard biopsy slides (H\u0026amp;E staining), before cutting additional tissue for immunohistochemistry. This matters because biopsy tissue is limited \u0026ndash; every additional test consumes irreplaceable material.\nValidated platforms:\nHEX (Stanford, Nature Medicine 2026) \u0026ndash; predicts 40 proteins and immune phenotype from standard H\u0026amp;E slides. Open-source and free Paige Predict (Tempus, commercial since January 2026) \u0026ndash; predicts 123+ biomarkers from H\u0026amp;E Not all centers have adopted these tools yet. But if your biopsy is small and tissue is limited, ask: \u0026ldquo;Can AI-assisted pathology help prioritize which additional tests to run, to conserve tissue?\u0026rdquo;\nStep 3c: Liquid biopsy \u0026ndash;diagnosis and monitoring from blood A liquid biopsy (ctDNA test) detects tumor DNA fragments circulating in your blood. It requires only a blood draw \u0026ndash; no needle in the tumor.\nWhen it helps at diagnosis:\nWhen the tumor is in a location difficult to biopsy (deep lung, brain, bone) When the biopsy yielded insufficient tissue for molecular testing As a complement to tissue biopsy \u0026ndash; liquid biopsy can detect mutations the tissue sample missed, and vice versa When it helps during treatment:\nDetects resistance mutations 3-6 months before imaging shows progression Confirms treatment response at the molecular level (ctDNA clearance at week 8 is the strongest predictor of outcome) Monitors for minimal residual disease after local treatment (surgery, radiation, ablation) Available platforms: FoundationOne Liquid CDx (300+ genes, available through partner labs in many countries including Romania), Guardant360 CDx (74 genes), and ultra-sensitive personalized platforms like Signatera and Haystack MRD for ongoing monitoring.\nTip Liquid biopsy does not replace tissue biopsy \u0026ndash; the two are complementary. Tissue provides histology (what the cancer looks like under the microscope) and enough material for comprehensive testing. Liquid biopsy provides real-time molecular monitoring and catches what tissue may miss. Step 4: Complete staging \u0026ndash;leave nothing to chance In addition to the initial PET-CT, some cancers require additional staging investigations:\nBrain MRI Mandatory for:\nLung cancer \u0026ndash;high risk of brain metastases Melanoma \u0026ndash;high risk of brain metastases HER2+ breast cancer \u0026ndash;increased risk PET-CT does not \u0026ldquo;see\u0026rdquo; the brain well because of its naturally high metabolic activity. Brain MRI is the correct investigation.\nOther staging investigations Bone scintigraphy: for prostate cancer, breast cancer (when bone metastases are suspected) Pelvic MRI: for pelvic cancers (rectal, cervical, prostate) Ask your oncologist: \u0026ldquo;Is the staging complete? Do I also need a brain MRI?\u0026rdquo;\nStep 5: Tumor board \u0026ndash;doctors who talk to each other The tumor board (also called a multidisciplinary team meeting) is the session where all involved specialists review your case and jointly decide the treatment plan.\nWho participates? Medical oncologist \u0026ndash;the specialist in systemic treatments (chemotherapy, targeted therapy, immunotherapy) Surgical oncologist \u0026ndash;evaluates whether and when surgery is indicated Radiation oncologist \u0026ndash;evaluates whether radiation therapy is indicated Pathologist \u0026ndash;the one who read the biopsy, can review the diagnosis Radiologist \u0026ndash;reviews the imaging live Clinical trials coordinator \u0026ndash;checks whether you are eligible for clinical studies Plus: geneticist, nutritionist, palliative care specialist, psychologist, as needed Why does it matter so much? The numbers speak for themselves:\n40% of cases presented at tumor board have the treatment plan modified 29-45% of cases have diagnostic changes (the pathologist or radiologist discovers something new) In neuro-oncology: 59% of cases have clinical management changes Studies show significant reductions in mortality risk for patients discussed at tumor board Not all tumor boards are equal Daily: top specialized oncology centers have daily tumor boards. Your case is discussed quickly, without weeks of delay. Weekly: many large hospitals have tumor board once a week. Acceptable, but can add days of waiting. Nonexistent or superficial: some centers do not have a real tumor board. The decision is made by a single doctor. This is a red flag. Integrated information system In a good center, all doctors on the board have access to a single digital record \u0026ndash;imaging, pathology, lab results, everything. There is no more \u0026ldquo;I have not seen the colleague\u0026rsquo;s result\u0026rdquo; or \u0026ldquo;you need to bring the file from another hospital.\u0026rdquo;\nWarning DO NOT accept a treatment plan decided by a single doctor. Ask: \u0026ldquo;Will my case be presented at the tumor board? When? Can I find out what was decided?\u0026rdquo; If there is no tumor board, take that into consideration when choosing where to be treated. Step 5b: Free AI tools for genomic interpretation When your molecular testing results arrive, several free, clinically validated platforms can help you and your oncologist interpret them:\nOncoKB (Memorial Sloan Kettering) \u0026ndash; 8,000+ alterations classified by actionability level (FDA-approved, clinical evidence, investigational). Free for clinical use CIViC (Washington University) \u0026ndash; crowd-curated clinical evidence database linking mutations to treatments. Open access ClinicalTrials.gov \u0026ndash; search your specific mutations to find open clinical trials worldwide These tools do not replace your oncologist\u0026rsquo;s judgment. They complement it by ensuring no actionable finding is overlooked \u0026ndash; especially for rare mutations where even experienced oncologists may not be aware of every option.\nTip On the day you receive molecular results: Enter each identified mutation into OncoKB. If any mutation shows \u0026ldquo;Level 1\u0026rdquo; or \u0026ldquo;Level 2\u0026rdquo; evidence for a treatment you are not receiving, bring this to your next oncology appointment. Step 6: Second opinion \u0026ndash;it is not optional, it is responsible Asking for a second medical opinion is not an insult to your doctor. It is a responsible step that any good doctor respects.\nWhen is it necessary? Always for rare cancers or unusual molecular subtypes When the proposed treatment plan does not seem clearly explained to you When you did not have a tumor board When something feels off \u0026ndash;trust your instincts How to ask without feeling awkward? Simply say: \u0026ldquo;I want to make sure we are doing the best possible thing. I would like a second opinion at another center.\u0026rdquo; A good doctor will not be offended. If they are offended, that is itself a signal.\nTip Prepare a complete file before the second opinion: imaging on CD/DVD or link, histopathology report, molecular testing results, all blood tests. The more complete the file, the more valuable the opinion will be. Where it matters to go: specialized oncology centers Not all hospitals are equal when it comes to oncology diagnosis. A specialized oncology center makes the difference through: state-of-the-art equipment, daily tumor board, rapid molecular testing, and an integrated system where all doctors see all the information.\nReal-world experience: Anadolu Medical Center, Istanbul A patient with lung cancer had the following experience at Anadolu Medical Center:\nPET-CT as the first step \u0026ndash; done immediately, with state-of-the-art equipment (low doses, high resolution, results in 24 hours) CT-guided biopsy \u0026ndash; from the area with the highest tumor activity, identified on PET-CT Rapid molecular testing \u0026ndash; subset in 3 days, full NGS panel in 10 days Daily tumor board \u0026ndash; the case discussed by all specialists together, not passed from one doctor to another Single information system \u0026ndash; all doctors have access to all information, zero fragmentation Complete diagnosis + first treatment (CyberKnife) in 10 days What made the difference: Anadolu is a specialized oncology center \u0026ndash; this is what they do continuously. They have concentrated experience, high case volumes, and optimized protocols. It is not a general hospital that \u0026ldquo;also does oncology.\u0026rdquo;\nTip This is not an advertisement for a specific center. It is an example of how any serious oncology center should operate. Use these benchmarks as a standard when evaluating where to be treated. Leading oncology centers in Europe and Turkey If you are evaluating options for diagnosis or second opinion, here are renowned centers with internationally recognized oncology expertise:\nTurkey:\nAnadolu Medical Center, Istanbul \u0026ndash; specialized oncology center, academic partner of Johns Hopkins (USA). Daily tumor board, AI PET-CT, rapid molecular testing. France:\nGustave Roussy, Paris \u0026ndash; one of the largest oncology centers in Europe. Pioneer of rapid diagnosis (one-day breast diagnosis, since 2004). Institut Curie, Paris \u0026ndash; excellence in oncology research and treatment Germany:\nCharite Comprehensive Cancer Center, Berlin \u0026ndash; top university center Heidelberg University Hospital \u0026ndash; leader in oncology research University Hospital Munich (LMU) \u0026ndash; comprehensive cancer center Other European centers:\nNetherlands Cancer Institute (NKI), Amsterdam \u0026ndash; cutting-edge research and treatment Karolinska University Hospital, Stockholm \u0026ndash; excellence in oncology When evaluating a center, ask: Do they have a tumor board dedicated to my cancer type? How long do molecular tests take? What generation of PET-CT do they have? Do they have an integrated information system? Also check ClinicalTrials.gov for active clinical trials in your area.\nWhat NOT to do \u0026ndash; summary Here are the most common and costly mistakes you can avoid:\nDO NOT accept a biopsy without PET-CT \u0026ndash; you need to know the extent of the disease first DO NOT start treatment without molecular testing \u0026ndash; you may miss the treatment that suits you best DO NOT accept a plan from a single doctor \u0026ndash; ask for a tumor board DO NOT settle for 21+ day wait times for tests \u0026ndash; faster options exist DO NOT make major decisions in the first 48 hours \u0026ndash; emotions are at their peak, information is at its minimum DO NOT search Google randomly \u0026ndash; unverified information increases panic without real benefit DO NOT assume your doctor does everything automatically \u0026ndash; be your own advocate, ask, verify, request Timeline: what is normal vs cause for concern Stage Specialized center Fragmented pathway Red flag PET-CT + result 1-2 days 1-2 weeks \u0026gt; 3 weeks Biopsy + pathology result 3-7 days 1-3 weeks \u0026gt; 3 weeks Molecular testing 3-10 days 2-4 weeks \u0026gt; 4 weeks Tumor board Daily Weekly Does not exist Total: suspicion to treatment plan ~10 days 4-8 weeks \u0026gt; 8 weeks If your complete diagnosis takes longer than 8 weeks, actively ask what is causing the delay and whether faster options exist \u0026ndash;including at another center.\nUse AI tools as an ally in your journey Artificial intelligence tools (ChatGPT, Claude, Gemini, and others) can be a valuable ally in your diagnostic journey. They do not replace your doctor, but they can help you:\nUnderstand medical terms \u0026ndash; copy a paragraph from your pathology or imaging report and ask for an explanation in plain language Prepare questions for your doctor \u0026ndash; describe your situation and ask for a list of relevant questions to bring to your next appointment Verify information \u0026ndash; if you read something online and are not sure whether it is correct, ask the AI to check against NCCN or ESMO guidelines Understand treatment options \u0026ndash; ask for explanations about the difference between two proposed treatments, side effects, relevant clinical trials Translate medical documents \u0026ndash; if you have reports in another language, AI can translate and explain simultaneously Compare treatment options \u0026ndash; check our molecular subtype guides for detailed information, then discuss with your doctor Tip When using AI for medical information, be specific: include your cancer type, stage, mutations (if you know them), and what treatment you are on. The more context you provide, the more relevant the answer will be. Always verify the information with your medical team. What to do now Ask for a whole-body PET-CT as the first step, before biopsy Tell the doctor performing the biopsy that you need enough material for NGS molecular testing Ask explicitly about molecular testing \u0026ndash;what is being tested, when will results come, is there a rapid panel? Request presentation at the tumor board \u0026ndash;ask when it will be and what was decided Prepare your file for a second opinion \u0026ndash;imaging, pathology, molecular tests, lab results The content of this article is for informational purposes only and does not constitute medical advice. Discuss any medical decision with your oncologist. If you have urgent symptoms, contact a doctor immediately. ","permalink":"https://oncoguide.github.io/en/diagnosis/complete-diagnosis-guide/","summary":"\u003cp\u003e\u003cstrong\u003eYou just found out you have cancer. Or that there is a serious suspicion. The world has stopped.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eI know what you are going through. I have been there.\u003c/p\u003e\n\u003cp\u003eIn moments like these, the instinct is to do anything \u0026ndash;immediately. To accept the first plan someone proposes. To rush into treatment. But here is what I learned the hard way: \u003cstrong\u003ethe most important thing you can do right now is to reach a complete and accurate diagnosis before making any treatment decision.\u003c/strong\u003e\u003c/p\u003e","title":"The Complete Oncology Diagnosis Guide: Step by Step"},{"content":"If you are reading this, it means you have made it through the first few months. You have the diagnosis, you have the treatment, you understand the basics. Selpercatinib is working \u0026ndash; the tumor has probably shrunk, you probably feel better than you expected.\nAnd yet, the question that never goes away: how long will it last?\nThis guide is for you. Not to scare you, but to show you that there are options your oncologist does not always mention \u0026ndash; not because they are irrelevant, but because they are new, specialized, and not (yet) part of standard protocols. Your oncologist remains the central piece of your treatment. This guide gives you the tools to have a more informed conversation with them.\nIf you are just starting out, first read the complete guide for newly diagnosed patients. This article picks up where that one ends.\nIf you are a physician: this article is designed as a complement to clinical practice \u0026ndash; a structured inventory of emerging options for RET+ lung cancer, with references. The goal is to facilitate the physician-patient dialogue, not to replace it.\nThe problem with \u0026ldquo;wait and see\u0026rdquo; The current standard of care for RET fusion lung cancer looks like this:\nDiagnose the RET fusion through molecular testing (NGS) Start Selpercatinib (RETSEVMO) Monitor with CT every 2-3 months When the tumor progresses, switch treatment This protocol works. Selpercatinib offers an 84% response rate as first line, and the median progression-free survival is nearly 25 months. Compared to traditional chemotherapy, that is an enormous difference.\nBut \u0026ldquo;median\u0026rdquo; means half of patients progress before 25 months. Some resistance mechanisms appear early: solvent front mutations (G810) can be detected on ctDNA at just 3-4 months, and MET amplification \u0026ndash; the most common bypass mechanism \u0026ndash; appears on average at 8 months. Other patients remain stable well past 3 years. Every case is different.\nBut the strategy remains passive. You wait for the disease to return, then react.\nWhat \u0026ldquo;standard of care\u0026rdquo; means and why it matters:\n\u0026ldquo;Standard of care\u0026rdquo; is the treatment that hospitals and clinics routinely apply. For a new treatment to reach this level, it must go through rigorous clinical trials \u0026ndash; Phase 1 (safety), Phase 2 (efficacy), Phase 3 (direct comparison with existing treatment). This process has traditionally taken many years, but the pace is accelerating. Selpercatinib, for example, received accelerated FDA approval just 3 years after the first patient was treated, and programs like \u0026ldquo;breakthrough therapy\u0026rdquo; and \u0026ldquo;expanded access\u0026rdquo; are constantly shortening the path from discovery to patient.\nNevertheless, many of the options described in this article have not yet gone through all stages \u0026ndash; not because they do not work, but because the process, although increasingly faster, requires time and validation across hundreds or thousands of patients. Your oncologist follows validated protocols \u0026ndash; and is right to do so. This guide does not contradict their protocol, but shows you what complementary options exist beyond it, with what level of evidence, and how you can discuss them in an informed way.\nThe fundamental problem remains: at stage IV, nearly every patient will develop resistance at some point. The question is not \u0026ldquo;if\u0026rdquo; but \u0026ldquo;when\u0026rdquo; \u0026ndash; and \u0026ldquo;what have you prepared for that moment.\u0026rdquo;\nThe good news: technology has advanced enough that proactive action is now possible. We are not talking about baseless experimental treatments. We are talking about options with clinical trials, published data, and solid biological rationale \u0026ndash; available now or within the next 1-3 years.\nThe window of opportunity is now, while treatment is working. Your immune system and treatment response are at their best. Once resistance sets in, options narrow.\nAdvanced molecular profiling \u0026ndash; know your enemy The NGS test that confirmed the RET fusion was just the beginning. There are much deeper layers of molecular information that directly influence what options you have.\nBeyond NGS: complete sequencing Whole Exome Sequencing (WES) analyzes all genes in your tumor, not just a panel of 50-500. Why it matters:\nIdentifies co-mutations that influence prognosis (TP53, PIK3CA, KEAP1) Finds tumor neoantigens \u0026ndash; protein fragments unique to your tumor that the immune system can recognize. They are the basis of personalized vaccines Detects DNA repair defects (FANCL, BRCA, ATM) that can open additional therapeutic options, such as PARP inhibitors RNA-seq goes even further: it shows which genes are actually active in your tumor, not just present. It can confirm the RET fusion partner (KIF5B, CCDC6, etc.) with certainty and detect resistance mechanisms that do not appear at the DNA level.\nTip In practice: Ask your oncologist for a referral for WES + RNA-seq on tumor tissue. If you already have a stored biopsy (paraffin block, called FFPE) at a laboratory, that may be sufficient. Laboratories with experience in molecular oncology are available throughout Europe. Important note: These advanced tests are not always covered by public health insurance; check with your oncologist whether they are covered or require private payment. There are also European academic programs that offer free sequencing for eligible patients, though international access typically requires cross-border referral or an S2 form. Specific biomarkers that open trial options Beyond general sequencing, a few specific biomarkers are worth explicitly testing because they gate access to emerging treatment classes:\nMTAP loss (methylthioadenosine phosphorylase) \u0026ndash; A peer-reviewed 2026 study (Aldea et al., Annals of Oncology, March 2026) documented MTAP loss in 18-35% of RET fusion-positive NSCLC patients \u0026ndash; a high prevalence that opens eligibility for PRMT5 inhibitors, a new class of targeted therapies currently in phase 2-3 trials. MTAP status is best confirmed by IHC on tumor tissue (not by liquid biopsy, which cannot reliably detect MTAP deletions). If you have a stored FFPE biopsy, MTAP IHC can be added at marginal additional cost. RB1 status (tumor suppressor gene) \u0026ndash; Relevant for understanding lineage plasticity risk (see the \u0026ldquo;Resistance mechanisms\u0026rdquo; section below). Usually reported as part of a standard NGS panel; worth confirming is included. Ask your oncologist whether these markers are part of the panel already run. If not, they can often be added to the existing tissue sample at marginal additional cost.\nGenetic testing: not just the tumor, but also you Three genetic tests that matter beyond the tumor:\n1. Germline (hereditary) testing\nThe tumor has acquired mutations, but some may be inherited. For example, mutations in the FANCL or BRCA genes may indicate a vulnerability in DNA repair \u0026ndash; which opens therapeutic options (PARP inhibitors) and has implications for blood relatives.\n2. HLA typing\nHLA genes determine which protein fragments your immune system can \u0026ldquo;see.\u0026rdquo; They are essential for:\nEligibility for anti-cancer vaccines (some require specific HLA types) Design of personalized vaccines (neoantigens are filtered through your HLA type) Immunotherapy planning A simple blood test, performed once.\n3. Pharmacogenomics\nHow your body metabolizes medications. Selpercatinib is processed by the CYP3A4 and CYP2C8 enzymes. Genetic variants in these enzymes can explain why some patients have more side effects than others at the same dose.\nImportant Ask your oncologist: \u0026ldquo;Have I been tested for germline mutations? Do we know if I have inherited mutations in DNA repair genes?\u0026rdquo; If the answer is no, request a referral. ctDNA \u0026ndash; real-time disease monitoring Imaging (CT, PET-CT) shows what the tumor looked like weeks ago. Circulating tumor DNA (ctDNA) shows what the tumor is doing today.\nWhat is ctDNA Tumor cells release DNA fragments into the bloodstream. These can be detected through a simple blood draw \u0026ndash; no biopsy, no anesthesia. It is called a liquid biopsy.\nWhy it matters ctDNA can detect disease progression 3-6 months before it becomes visible on imaging. In practice, this means:\nYou detect resistance early, when intervention options are at their maximum You can identify the mechanism of resistance (RET mutation, MET amplification, KRAS activation) directly from blood You can monitor treatment response without additional radiation After local treatment (radiotherapy, cryoablation), undetectable ctDNA is a strong indicator of complete response Available platforms There are multiple ctDNA monitoring platforms, with different levels of sensitivity:\nNote: Sensitivity is measured in VAF (Variant Allele Frequency) \u0026ndash; the minimum percentage of mutant DNA out of total circulating DNA that the test can detect. The smaller the number, the finer the traces of disease the test can pick up.\nPlatform What it measures Sensitivity Availability Guardant360 74 genes, fixed panel 0.1% VAF Europe (through partner laboratories) FoundationOne Liquid CDx 300+ genes, fixed panel 0.1-0.5% VAF Europe and USA Signatera (Natera) 16 personalized variants from your tumor (fixed from initial biopsy) 0.01% VAF EU (CE-IVD marked) NeXT Personal (Personalis) Tumor-informed hybrid-capture, can track emergent resistance variants during treatment 1.7 ppm (0.00017%) US + EU via partner laboratories Haystack MRD (HPH Hamburg) 50 variants from tumor WGS 0.0006% Germany, accessible EU-wide The difference between fixed panels and personalized monitoring is enormous. A fixed panel like Guardant360 detects known mutations at a relatively high level. A personalized platform (Signatera, NeXT Personal, Haystack) detects traces of disease 100-1000 times smaller \u0026ndash; essential for confirming whether the disease has been completely eliminated.\nA further distinction matters for patients already on treatment months in: most personalized platforms (Signatera, Haystack) track a fixed set of variants selected from your initial tumor biopsy. If new resistance mutations emerge during treatment, those fixed panels may not see them. NeXT Personal (Personalis) introduced in April 2026 a \u0026ldquo;Real-Time Variant Tracker\u0026rdquo; capability that uses hybrid-capture to detect new mutations as they appear during therapy \u0026ndash; useful for early detection of emerging resistance. Ask your lab which approach they use and whether emergent-mutation tracking is available.\nWhen to test Timepoint Why At diagnosis (before treatment) Baseline reference At 8-12 weeks of treatment Confirmation of molecular response Before local therapy (SBRT/cryo) Quantification of residual disease At 4-6 weeks after local therapy Response confirmation \u0026ndash; undetectable ctDNA = excellent prognosis Every 3 months thereafter Continuous molecular surveillance Tip ctDNA monitoring is not (yet) standard of care in most countries. But it is available, clinically validated, and provides information that imaging cannot. Discuss with your oncologist about integrating it into your monitoring plan. Practical access in Romania and the EU FoundationOne Liquid CDx (Roche/Foundation Medicine) is the most widely used broad-panel liquid biopsy test (300+ genes) and is available in Romania through partner laboratories, including the Regina Maria network and other molecular oncology centers. The test requires only a blood draw and provides results in 2-3 weeks.\nGuardant360 CDx is accessible in the EU through partner laboratories in Germany (TherapySelect) or the UK.\nSignatera (Natera) \u0026ndash; the personalized MRD (minimal residual disease) monitoring platform \u0026ndash; has CE-IVD marking and is available in the EU through Oncompass Medicine (Hungary/Switzerland).\nHaystack MRD (HPH Hamburg) \u0026ndash; the most sensitive platform available in Europe \u0026ndash; accepts samples from across the EU.\nFor personalized platforms (Signatera, Haystack), the first step is sending the tumor NGS result (from biopsy) to the laboratory, which creates a personalized monitoring profile. Afterward, each test requires only a blood draw.\nImportant Ask your oncologist: \u0026ldquo;Can we add ctDNA monitoring to my plan? Which partner laboratory do you recommend?\u0026rdquo; If your oncologist is not familiar with these tests, you can contact the laboratories mentioned above directly \u0026ndash; all of them accept samples sent by patients through their treating physician. Consolidative local therapy \u0026ndash; treat what remains If treatment is working and you have a small number of residual lesions (1-5 sites), you do not have to wait for progression. You can actively treat what remains, while Selpercatinib controls the rest of the disease.\nThis concept is called consolidative local therapy (CLT) and has solid evidence from randomized trials.\nWhy it works The logic is simple: if 90% of the disease responds to Selpercatinib, but a few lesions have cells that could develop resistance, destroying them now eliminates the source of future problems.\nThe evidence is strong:\nSINDAS (randomized trial, Phase III): SBRT + TKI vs TKI alone \u0026ndash; median survival +8 months (25.5 vs 17.4 months) SABR-COMET (8-year follow-up): 21% of patients progression-free at 8 years \u0026ndash; a cure signal in 1 out of 5 oligometastatic patients LIBRETTO-001 (RET-specific data): Continuing selpercatinib + SBRT at oligoprogression adds +9.8 months of progression-free survival The optimal window for CLT: months 4-6 from starting treatment, when response is maximal but residual lesions are still visible on imaging.\nLocal treatment options SBRT (stereotactic body radiation therapy) A focused radiation beam destroys the tumor with millimeter precision, in 1-5 sessions. It is the most studied form of CLT.\nAdvantages:\nLocal control \u0026gt;95% at 1 year Outpatient, no anesthesia Low risk of pneumothorax Covered by insurance in many countries Limitations:\nCumulative doses limit repeatability At standard ablative doses, tumor antigens can be denatured by radiation \u0026ndash; systemic immune activation is often modest Two dosing philosophies:\nSBRT can be delivered with two different intents, and the correct choice depends on the clinical objective:\nIntent Typical dose What it does Local control Immune activation Ablative (tumor destruction) BED \u0026gt; 100 (e.g., 54 Gy/3 fx or 50 Gy/5 fx) Completely destroys tumor tissue \u0026gt;95% at 1 year Moderate (antigens partially denatured by high-dose radiation) Immunogenic (immune activation) Lower BED (e.g., 8 Gy x 3 fx) Fragments tumor while keeping antigens more intact Inferior Superior (stays below the Trex1 enzyme threshold, which degrades cytoplasmic DNA) The PEMBRO-RT trial used the immunogenic dose (8 Gy x 3) combined with pembrolizumab and achieved 41.7% abscopal response even in \u0026ldquo;cold\u0026rdquo; tumors. But local control of the irradiated lesion is lower than with ablative doses.\nIn practice, the radiation oncologist may choose an intermediate or ablative dose for the primary lesion (local control priority) and an immunogenic dose for a secondary lesion (immune activation priority). The decision belongs strictly to the radiation oncologist, depending on tumor location, the priority goal for each lesion, and the overall treatment strategy.\nCryoablation \u0026ndash; the \u0026ldquo;in-situ vaccine\u0026rdquo; Cryoablation destroys the tumor through repeated freeze/thaw cycles, using a CT-guided probe inserted percutaneously.\nWhat makes it special: Unlike heat or radiation, cryoablation preserves tumor antigens intact \u0026ndash; the tumor proteins remain recognizable to the immune system. The result:\nSTING pathway activation (immune signaling pathway) without PD-L1 overexpression NK cell and CD8+ lymphocyte expansion Potential abscopal effect \u0026ndash; untreated distant tumors shrink Clinical evidence:\nBOOSTER (randomized trial): Cryo + immunotherapy vs immunotherapy alone \u0026ndash; progression-free survival 26.7 vs 11.7 months (HR 0.213). The strongest clinical effect demonstrated for cryoablation ECLIPSE (Gustave Roussy, 5 years): Local control 79.2% at 5 years \u0026ndash; the longest follow-up for pulmonary cryoablation in the world JVIR 2026 meta-analysis (786 patients): Local control at 1 year 90.5%. For tumors under 2 cm, 3-year control reaches 96-100% SOLSTICE (128 patients, 7 centers): Local control after re-cryoablation rises to 91.1% \u0026ndash; cryoablation is repeatable without limit, with no cumulative dose Robotic vs manual cryoablation:\nRobotic platforms (Perfint MAXIO, Quantum Epione) offer precision of 1.7-6.1 mm, major complications of only 3%, and over 80% reduction in radiation exposure for the patient. They are available at a few reference centers in Europe, but do not yet have long-term data (the technology is 3-5 years old). Manual CT-guided cryoablation has two decades of experience and proven results.\nLimitations:\nRisk of pneumothorax (15-25% for tumors under 2 cm; 75% resolve spontaneously) Does not produce tumor tissue for analysis \u0026ndash; cryoablation destroys in-situ. If you need tissue for molecular testing or vaccines, a separate biopsy during the same session is required Important European reference centers for pulmonary cryoablation:\nGustave Roussy (Paris) \u0026ndash; the largest global experience (~600+ patients), ECLIPSE/SOLSTICE programs, robotic capability (Quantum Epione) + conventional, integration with MATCH-R for molecular profiling Royal Marsden (London) \u0026ndash; published data with robotic cryoablation (97% local control at 12 months on 37 pulmonary lesions), shortest TKI pause protocol (24-48h) IEO Milan \u0026ndash; vast experience in general ablation (6000+ procedures), IceCure ProSense platform (liquid nitrogen, -196C) Surgery Rarely indicated at stage IV, but may be considered if:\nThe residual lesion is solitary and completely resectable There is a need for fresh tumor tissue for functional testing or vaccines Other local options are not anatomically feasible What to choose: SBRT, cryo, or surgery? Criterion SBRT Cryoablation Surgery 1-year local control 95%+ 90.5% 95%+ Immune activation Moderate Superior Minimal Repeatability Limited Unlimited Limited Tissue for analysis No No (requires separate biopsy) Yes Pneumothorax risk \u0026lt;1% 15-25% Variable Recovery time Days Days Weeks Selpercatinib pause 3-7 days 1-3 days 7+ days The optimal approach may combine methods: for example, cryoablation on the primary tumor (for immune activation) and SBRT on the bone metastasis (for maximum local control).\nTip Ask your oncologist: \u0026ldquo;Do I have oligometastatic disease? Would stereotactic radiotherapy or cryoablation be appropriate for the residual lesions, while continuing Selpercatinib in parallel?\u0026rdquo; Anti-cancer vaccines \u0026ndash; train your immune system Therapeutic anti-cancer vaccines do not prevent cancer. They train the immune system to recognize and attack existing tumor cells. And RET fusion cancer has a unique advantage in this space.\nWhy the RET fusion is an ideal vaccine target The RET fusion occurs when two genes (for example, KIF5B and RET) join abnormally. At the junction point, a protein sequence that does not exist anywhere in the normal body is formed \u0026ndash; a perfect tumor neoantigen.\nThis means:\nZero risk of autoimmunity \u0026ndash; the vaccine targets something only the tumor has The tumor cannot escape without losing the mutation it depends on for survival A single design covers all patients with the same fusion type (e.g., KIF5B-RET) Unlike other cancers where each patient must be sequenced individually, the RET fusion offers a shared, clonal, and specific target.\nTypes of vaccines 1. Peptide vaccines (protein-based) The simplest concept: a synthetic protein fragment (peptide) from the fusion junction, injected with an adjuvant that stimulates the immune response.\nFusionVAC (University of Tubingen, Germany):\nProven platform on other cancers with genetic fusions \u0026ndash; in the Phase 1 trial on the DNAJB1-PRKACA fusion (Nature Medicine 2025): 75% disease control (9 out of 12 patients), 3 patients with no detectable disease, one patient on compassionate use cancer-free for over 4 years. Note: these results are from a different cancer type (fibrolamellar carcinoma), not RET+ lung cancer. The platform is modular \u0026ndash; it adapts to any fusion, but RET-specific clinical data do not exist yet The 22-amino acid peptide covers 93-96% of the European population, without requiring specific HLA typing The XS15 adjuvant is specifically designed for immunocompromised patients (relevant, since 52% of selpercatinib patients develop lymphopenia) Requires fresh frozen tumor tissue (-80C) for feasibility assessment and vaccine design. Paraffin blocks (FFPE) are not sufficient. This means biopsy planning is essential \u0026ndash; at any future intervention (cryoablation, CT-guided biopsy), explicitly request that tissue cores be preserved in cryopreservation at -80C for Tubingen Estimated production time of a few weeks at the GMP facility in Tubingen (peptide synthesis, not cell culture) Access: Through the German \u0026ldquo;individual use\u0026rdquo; procedure (Individueller Heilversuch) Important For the FusionVAC vaccine, the RET fusion partner must be confirmed (KIF5B vs CCDC6 vs other). Each fusion partner creates a different junction and requires a different peptide design. Confirmation is done through extended tumor genetic sequencing (WES or RNA-seq, described above). Validated KIF5B-RET neopeptides:\nNNDVKEDPK \u0026ndash; strongest HLA-C*07:02 binder, immune response experimentally confirmed (Gunaratne, Frontiers in Immunology 2025) KEDPKWEFP \u0026ndash; second immunogenic hit 15 TCR clonotypes identified, 5 with high activation markers The FusionNeoAntigen database (Oxford) maps KIF5B-RET to 92 HLA-I alleles, covering approximately 94% of the global population 2. mRNA vaccines The same technology from the COVID vaccines, adapted for oncology. A messenger RNA encodes the tumor antigens, and the body\u0026rsquo;s cells produce and present them to the immune system.\nBNT116 (BioNTech) + Cemiplimab:\nEncodes 6 common tumor antigens (not RET fusion-specific) Phase 1/2 ongoing: 45% response rate, 80% disease control in NSCLC Active clinical trial at multiple European centers (including Turkey) Limitation: Most protocols exclude patients with driver mutations (EGFR, ALK, RET) \u0026ndash; eligibility verification is essential V940/mRNA-4157 (Moderna + Merck):\nPersonalized vaccine: encodes up to 34 unique neoantigens from your tumor Combined with pembrolizumab (Keytruda) Results in melanoma: 44% reduction in recurrence Phase 3 for NSCLC (INTerpath-002) \u0026ndash; actively recruiting, estimated results ~2030+ mRNA-4359 (Moderna, Mobilize Trial):\nExplicitly accepts patients with driver mutations (including post-TKI) Personalized vaccine with up to 34 neoantigens Combined with pembrolizumab 3. Dendritic cell vaccines Dendritic cells are the \u0026ldquo;teachers\u0026rdquo; of the immune system \u0026ndash; they present tumor antigens directly to T lymphocytes, activating a targeted immune response.\nIOZK (Cologne, Germany) \u0026ndash; IO-VAC:\nAutologous dendritic cells (from the patient\u0026rsquo;s blood), loaded with tumor antigens Combined with oncolytic Newcastle Disease Virus (NDV) and hyperthermia 350+ patients treated annually No restrictions related to standard immune markers (PD-L1, TMB \u0026ndash; tumor mutational burden) or driver mutations Important limitation: Requires fresh or frozen tumor tissue (FFPE does not work). Also has limited data in lung cancer, with zero RET+-specific data PDC*lung01:\nAllogeneic dendritic cells (pre-manufactured, standardized) \u0026ndash; does not require the patient\u0026rsquo;s own tumor tissue Phase 1/2: 51-55% response rate in combination with immunotherapy Limitation: Requires HLA-A*02:01 (present in approximately 40% of Europeans) CeGaT CancerNeo (Tubingen, Germany):\nComplete pipeline: tumor sequencing, AI neoantigen prediction, GMP synthesis, administration 90% immune response rate (87 out of 97 patients) Median survival of 53 months in responders, compared to 27 without response Accepts FFPE (important advantage if you already have a stored biopsy) Production time: approximately 2 months 4. Personalized neoantigen vaccines The most advanced concept: complete sequencing of your tumor, identification of all unique neoantigens, and creation of a vaccine targeting all of them.\nAdvantages: Broad coverage (the tumor cannot escape by losing a single antigen). Disadvantages: Higher cost, longer production time (2-5 months).\nActive companies and programs:\nCeGaT CancerNeo (Tubingen, Germany) \u0026ndash; described above, complete pipeline from sequencing to administration. Accepts FFPE Jaime Leandro Foundation (USA) \u0026ndash; personalized neoantigen peptide vaccine. Explicitly accepts lung cancer. 48 patients treated (August 2025). Access through FDA Expanded Access (Form 3926, approval rate \u0026gt;99%). Production: 4-5 months BioNTech Individualized Neoantigen Therapy (iNeST/BNT122) \u0026ndash; personalized mRNA platform (autogene cevumeran). Phase 2 in pancreatic cancer and melanoma, with significant reduction in recurrence. Extension to NSCLC is anticipated Moderna mRNA-4157/V940 \u0026ndash; described above under mRNA vaccines. Up to 34 personalized neoantigens per patient Gritstone Bio (GRANITE/SLATE) \u0026ndash; combined platform: adenoviral vector (prime) + self-amplifying mRNA (boost). Phase 2 in MSI-stable solid tumors (direct relevance for RET+, which is MSI-stable) Most of these programs are accessible through clinical trials or compassionate use. CeGaT is the only one with direct commercial access in Europe.\nTip FusionVAC and CeGaT CancerNeo \u0026ndash; complementary, not competing\nBoth programs are in Tubingen, but are independent entities: FusionVAC is a research program of the University Hospital (Prof. Walz), and CeGaT is a private company with a commercial service. The essential difference:\nFusionVAC = a precise bullet targeting the RET fusion junction (a single antigen, the most important one) CeGaT CancerNeo = broad coverage of all unique mutations in your tumor (dozens of antigens) Theoretically, they can be combined: FusionVAC for the primary target (the fusion) + CeGaT for broader coverage. FusionVAC requires fresh frozen tissue, CeGaT accepts FFPE too \u0026ndash; so they can work from different tissue sources.\nVaccines: what is available now vs what is coming Availability Options Available now (compassionate use/commercial) FusionVAC (Tubingen), CeGaT CancerNeo (Tubingen), IOZK IO-VAC (Cologne) Active clinical trials BNT116, mRNA-4359/Mobilize, PDC*lung01, V940 1-3 years Personalized mRNA vaccines specific to RET, KAIST B-cell AI vaccines 3-5+ years Anti-RET PROTACs, next-gen lipid mRNA The combination that amplifies efficacy Vaccines work best when combined with other treatments that amplify the immune response. The optimal evidence-based sequence:\nImmune activation (ANKTIVA/IL-15 \u0026ndash; see next section) \u0026ndash; restores lymphocytes before vaccination Vaccination (FusionVAC or another platform) \u0026ndash; trains the immune system Cryoablation \u0026ndash; releases tumor antigens in-situ, amplifying the vaccine\u0026rsquo;s effect Vaccine booster at 6-12 weeks after cryoablation \u0026ndash; within the window of maximum immune activation Continuing Selpercatinib throughout \u0026ndash; tyrosine kinase inhibitors (TKIs, the class to which Selpercatinib belongs) upregulate HLA class I on tumors, making them more visible to vaccine-trained T cells Warning No anti-cancer vaccine has yet cured RET fusion lung cancer. The evidence is strong from other cancer types with fusions, and the biological rationale is solid, but RET-specific clinical data are in early stages. These options are complementary to standard treatment, not a replacement. Immune system activation RET fusion cancer has an unfortunate characteristic: the tumor is immunologically \u0026ldquo;cold\u0026rdquo; \u0026ndash; few lymphocytes infiltrate it, PD-L1 expression is low. That is why classical immunotherapy (pembrolizumab, nivolumab) works poorly.\nBut that does not mean the immune system cannot be activated. It just requires different tools.\nANKTIVA (N-803) \u0026ndash; IL-15 superagonist ANKTIVA is a biologic drug that activates NK cells (natural killers) and CD8+ T lymphocytes without expanding regulatory T cells (which would suppress the immune response).\nWhy it matters for RET+:\nWorks independently of PD-L1 \u0026ndash; it does not matter that your tumor is \u0026ldquo;cold\u0026rdquo; Reverses lymphopenia (low lymphocyte counts) \u0026ndash; 80% of patients in trials achieved lymphocytes \u0026gt;1200/uL In the QUILT-3.055 trial (86 refractory NSCLC patients), PD-L1 negative patients had superior median survival compared to PD-L1 positive (15.4 vs 13.8 months) \u0026ndash; cold tumors benefited more Status:\nFDA approved (2024) and EC approved (February 2026) for bladder cancer Approved in Saudi Arabia (January 2026) for metastatic NSCLC \u0026ndash; the first global approval for lung cancer Phase 3 trial ResQ201A actively recruiting \u0026ndash; the first Phase 3 trial that explicitly includes RET+ patients Access in the EU:\nOff-label (EC-approved drug, use outside indication) Named patient programs (Everyone.org or Accord Healthcare, EU distributor) Clinical trial (ResQ201A \u0026ndash; requires progression after immunotherapy) Pembrolizumab (Keytruda) \u0026ndash; limited role, but not zero The LIBRETTO-431 trial clearly demonstrated: Selpercatinib alone is superior to chemotherapy + pembrolizumab as first line (84% vs 56% response rate). Pembrolizumab alone has a response rate of only 6-10% in RET+.\nWhen it could still help:\nAfter cryoablation: Tissue destruction + immune activation + systemic pembrolizumab \u0026ndash; the abscopal effect (PEMBRO-RT: 41.7% abscopal response even in cold tumors, with SBRT 8 Gy x 3 + pembrolizumab within 7 days) Combined with vaccines: Vaccines + checkpoint inhibitors \u0026gt; vaccine alone With ANKTIVA: IL-15 activates T lymphocytes, pembrolizumab \u0026ldquo;unblocks\u0026rdquo; them Warning Important risk: Patients who have received immunotherapy (pembrolizumab, nivolumab) have a 13.9% risk of hypersensitivity reaction upon reintroduction of selpercatinib (compared to 3.1% without prior immunotherapy). Treatment sequencing must be carefully planned. The abscopal effect \u0026ndash; treat one lesion, benefit all When you destroy a tumor (through cryoablation, SBRT, or even a vaccine), it releases antigens and danger signals. If the immune system is already activated (through ANKTIVA, vaccine, or checkpoint inhibitor), it can attack distant tumors you did not directly treat.\nThe combination that maximizes the abscopal effect: cryoablation (intact antigen release) + vaccine (specific training) + ANKTIVA (immune amplification).\nOn the horizon: cellular cancer therapies Beyond activating existing NK and T cells in the body, research is advancing toward adoptive cell therapies \u0026ndash; immune cells harvested, genetically modified in the laboratory, and reinfused into the patient.\nCAR-NK (chimeric antigen receptor NK cells): \u0026ldquo;Off-the-shelf\u0026rdquo; NK cells (from donors, not the patient) modified to recognize tumor markers. Advantage: does not require HLA matching, low risk of graft-versus-host disease. Multiple active clinical trials in NSCLC, but none specifically for RET+ TCR-T anti-RET: The only program in the world developing T cells genetically modified to specifically recognize peptides derived from the RET protein. Led by Dr. Alexandre Reuben at MD Anderson (Houston). Preclinical stage \u0026ndash; estimated 3-5 years until clinical trial These therapies are not available now, but represent an important direction for patients who exhaust current options. ANKTIVA remains the nearest available NK activation option today.\nDrug repurposing \u0026ndash; existing medications with anti-cancer potential Some medications approved for decades for other conditions have demonstrated anti-cancer properties in clinical or preclinical studies. They are inexpensive, available, and have well-known safety profiles.\nThe basic principle: As long as Selpercatinib is working, you do not want to add significant toxicity. Drug repurposing focuses on options with low risk and potential supplementary benefit.\nCandidates with evidence Aspirin (in studies, the dose of 100 mg/day with enteric coating was used)\nMechanism: Inhibits TXA2, which forms a \u0026ldquo;platelet shield\u0026rdquo; around circulating tumor cells, protecting them from the immune system. Aspirin removes this shield.\nEvidence: Retrospective study in NSCLC (Chen, Lung Cancer 2020): 21% reduction in death risk. Nature 2025: TXA2/Treg mechanism confirmed.\nWarning Caution: Selpercatinib has a documented 2.3% risk of severe hemorrhage. Aspirin additionally increases bleeding risk. Do not start aspirin without your oncologist\u0026rsquo;s explicit approval, who will evaluate the benefit/risk ratio in your specific case. Propranolol (in studies, 10-20 mg twice daily was used)\nMechanism: Non-selective beta-blocker that reduces adrenergic signaling \u0026ndash; chronic stress stimulates metastasis through beta-adrenergic receptors.\nEvidence: 2025 meta-analysis in lung cancer: distant metastasis-free survival HR 0.67, overall survival HR 0.78.\nPrecaution: Requires prior cardiology evaluation, especially in patients with low resting heart rate.\nRosuvastatin (in studies, doses of 10-20 mg/day were used)\nMechanism: HMG-CoA inhibitor \u0026ndash; blocks the mevalonate pathway, with anti-angiogenic effects and suppression of mutant p53 function. Important: not atorvastatin, simvastatin, or lovastatin, which are processed by CYP3A4 (the same enzyme as selpercatinib \u0026ndash; risk of toxic interaction).\nEvidence: 41% mortality reduction in combination with immunotherapy (JCI Insight 2022).\nVitamin D3 (in studies, doses of 4000-5000 IU/day were used)\nEvidence: DKFZ 2025 meta-analysis (14 randomized trials, \u0026gt;100,000 patients): -12% all-cause cancer mortality. Target in studies: 60-80 ng/mL in blood. Optimal dose should be determined by your physician based on your current level.\nMetformin (if indicated for diabetes or pre-diabetes)\nThe strongest level of evidence among all: a randomized trial (JAMA Oncology Japan) shows progression-free survival 13.1 vs 9.9 months and overall survival 31.7 vs 17.5 months in patients with driver mutations (EGFR+). The benefit is dependent on body mass index \u0026ndash; stronger in overweight patients. It is not prescribed off-label solely for the anti-cancer effect without a metabolic indication.\nWhat to avoid Substance Why Fenbendazole The case study was retracted (January 2026). Risk of hepatotoxicity. The Joe Tippens case was actually enrolled in a pembrolizumab trial (confounding factor) Ivermectin Zero evidence in NSCLC. Interaction with selpercatinib through P-gp Itraconazole Absolutely contraindicated \u0026ndash; strong CYP3A4 inhibitor, increases selpercatinib levels by 2.3x Atorvastatin CYP3A4 substrate \u0026ndash; use rosuvastatin instead High-dose antioxidant supplements May protect tumor cells from treatment effects Important None of these options replace Selpercatinib. They are complementary to standard treatment, with varying levels of evidence. Discuss with your oncologist before adding any medication, including seemingly harmless ones. Your role is not to prescribe, but to come prepared with informed questions. Next-gen RET inhibitors and ADCs \u0026ndash; your backup plan If Selpercatinib is working, why do you need a Plan B? Because resistance will appear at some point \u0026ndash; and when it does, you want to act fast, not search for options.\nWhy resistance occurs Two main mechanisms:\n1. On-target RET mutations (14%): The tumor modifies the RET protein itself, so selpercatinib can no longer bind. Most common: G810R/S/C (solvent front mutations).\n2. Bypass (off-target, 86%): The tumor activates another survival pathway, completely bypassing RET. Most common:\nMET amplification (18.2% \u0026ndash; most frequent and most aggressive, appears on average at 8.4 months) KRAS activation (7.1%) YAP/HER3/EGFR bypass (adaptive, appears early) MAPK reactivation (30% of cases) 3. Lineage plasticity \u0026ndash; the tumor changes identity\nA third, less-known mechanism: under sustained targeted therapy, some adenocarcinomas can transition toward a neuroendocrine phenotype \u0026ndash; the tumor changes what it is, not just how it responds. This was a major theme at AACR 2026 (MSK opening plenary by Charles Sawyers), documented across EGFR, ALK, and other targeted therapy classes. It is driver-agnostic, including RET.\nRB1 gene loss is the strongest predisposing biomarker. Patients with RB1 loss at baseline \u0026ndash; or acquired during treatment \u0026ndash; face a higher risk of this transition. Preclinical data (mostly from prostate cancer, cross-domain) suggests FGFR and JAK inhibitors may reverse lineage plasticity in RB1-deficient tumors, but this is not yet validated in NSCLC.\nClinical implication: If RB1 loss is detected on your NGS or ctDNA (now or later), a rebiopsy at progression becomes essential \u0026ndash; not just switching to a next-generation TKI. Neuroendocrine-phenotype disease responds to different drugs (platinum/etoposide-based regimens, not RET TKIs). Acting on imaging progression without re-confirming tumor biology risks choosing the wrong next treatment.\nNext-generation RET inhibitors These agents are designed to work where selpercatinib fails \u0026ndash; including solvent front mutations.\nAgent Response rate (ORR) Mutation coverage Brain penetration Status EP0031 (Lunbotinib) 69.7% G810R/S/C Yes Phase 2, recruiting at European centers Vepafestinib 30% (disease control: 80%) G810 + V804 Best in class Phase 1/2 (MARGARET) SY-5007 69.4% G810 Yes Phase 3 (the only one with Phase 3 data) APS03118 Preclinical G810 + V804 + L730 + Y806 Yes Broadest spectrum, Phase 1 EP0031 (Lunbotinib) is currently the most clinically advanced, with an active trial at European centers (VHIO Barcelona, Gemelli Rome, Christie Manchester, Sarah Cannon London).\nADCs (Antibody-Drug Conjugates) A new class of drugs: antibodies that deliver a chemotherapy payload directly to tumor cells, reducing systemic toxicity.\nRelevant for RET+ at progression:\nTelisotuzumab Vedotin (Emrelis) \u0026ndash; targets MET (the most common bypass mechanism). FDA approved 2025. Response rate 35% as monotherapy, 50% in combination. Available in Turkey Datopotamab Deruxtecan (Dato-DXd) \u0026ndash; targets TROP2. FDA approved 2025. Response rate 35.8% in driver-mutated cancers HER3-DXd (Patritumab Deruxtecan) \u0026ndash; targets HER3. Phase 2. Excellent results in brain and leptomeningeal metastases PROTACs \u0026ndash; the future of protein destruction PROTACs do not block the RET protein \u0026ndash; they completely destroy it through the cell\u0026rsquo;s recycling system (the proteasome). If the protein no longer exists, resistance mutations at the binding site become irrelevant.\nQZ2135 (Peking University): active on G810 variants RD-23: independent validation Estimate: 2028+ for clinical trial entry Combinations at progression If resistance appears, drug combination based on the identified mechanism is critical:\nIdentified mechanism Combination MET amplification Selpercatinib + capmatinib (documented CR) or crizotinib (4/4 responded) EGFR/HER3 activation Selpercatinib + afatinib BRAF fusion RET inhibitor + trametinib (near-complete response documented) KRAS mutation Selpercatinib + adagrasib/sotorasib NTRK fusion Selpercatinib + larotrectinib The golden rule: At progression, never stop selpercatinib without an alternative. Continue + add.\nTip Prepare now: Discuss with your oncologist about pre-screening for trials with EP0031 or vepafestinib. You do not have to be eligible today \u0026ndash; but when the time comes, you want to have the relationship established and documentation ready. The path to NED \u0026ndash; eradication strategy NED means No Evidence of Disease \u0026ndash; no evidence of disease. Not a cure (we cannot guarantee that), but the absence of any detectable sign of cancer.\nWhat NED means in practice Both criteria must be met simultaneously and sustained (minimum 6 months):\nNegative PET-CT at all known sites Undetectable ctDNA (\u0026lt;1 copy/mL) on an ultrasensitive platform Is it realistic? Yes. It is not guaranteed, but the data support it:\nSABR-COMET (8 years): 21% progression-free at 8 years \u0026ndash; a cure signal in 1 out of 5 oligometastatic patients LIBRETTO-432: Selpercatinib has curative potential in early stages CML (chronic myeloid leukemia) analogy: 40-60% of patients on imatinib (another TKI) achieve treatment-free remission \u0026ndash; they stop the medication and remain disease-free. RET fusion cancer is not CML, but the model is relevant Realistic probability for an integrated strategy (TKI + CLT + vaccines + immunomodulation):\n10-20%: Sustained functional NED (\u0026gt;5 years with no detectable disease) 40-50%: Long-term control (3-4+ years with minimal disease) 30-50%: Treatment does not generate detectable immune response \u0026lt;5%: Net risk (the safety profile of vaccines is excellent) The 4 phases of the eradication strategy Phase 1: Response and optimization (months 1-3)\nSelpercatinib as main line Complete molecular profiling (WES + RNA-seq + ctDNA baseline) Low-risk drug repurposing (aspirin, rosuvastatin, vitamin D) ctDNA monitoring at 8-12 weeks Phase 2: Consolidation + local therapy (months 4-6)\nPET-CT for re-evaluation Cryoablation/SBRT on residual lesions Biopsy for fresh tumor tissue (vaccines, functional testing) ctDNA pre and post intervention Phase 3: Immune activation (months 7-12)\nImmune activation (ANKTIVA \u0026ndash; lymphocyte recovery) Vaccination (FusionVAC or alternative) with booster at 6-12 weeks Cryoablation provides an immune amplification window ctDNA every 3 months Assessment of specific immune response (ELISpot anti-fusion T cells) Phase 4: TFR evaluation (from month 24)\nIf sustained negative ctDNA + negative PET-CT \u0026gt;12 months Discussion with oncologist about reducing or stopping TKI Intensive monitoring protocol: ctDNA every 3 months If disease returns: resume Selpercatinib (in CML, 96% re-response rate) The \u0026ldquo;Stay Paranoid\u0026rdquo; principle: Even at NED, never stop monitoring Real-world example: Sid Sijbrandij Sid Sijbrandij, co-founder of GitLab, publicly documented his strategy against cancer (osteosarcoma). When doctors told him he had exhausted the standard of care and there were no clinical trials for his situation, he went into \u0026ldquo;Founder Mode\u0026rdquo; \u0026ndash; he assembled a team of physicians and researchers, used AI to analyze medical data, and systematically explored every diagnostic and treatment option beyond standard protocols. The full story is on his blog and at sytse.com/cancer. It is not RET cancer, but it demonstrates that a proactive, informationally aggressive strategy is possible and can generate results beyond average statistics.\nBiobanking \u0026ndash; protect your future options At every biopsy or surgical intervention, explicitly request that a portion of tissue be properly preserved. This simple step can open options that do not exist today.\nWhy it matters Personalized vaccines require tumor tissue (either fresh or frozen) Functional testing (organoids, drug sensitivity) requires living tissue Complete molecular profiling works best on fresh frozen tissue (not just FFPE) If the tumor changes under treatment (and it will change), tissue from each biopsy is a \u0026ldquo;snapshot\u0026rdquo; of disease evolution What to request At every biopsy or intervention:\nFFPE (formaldehyde + paraffin) \u0026ndash; standard, sufficient for most molecular tests. This is done routinely anyway Cryopreservation at -80C \u0026ndash; essential for organoids, dendritic cell vaccines, and high-quality RNA sequencing. Must be explicitly requested Sufficient samples \u0026ndash; not a single fragment. Request 4-8 biopsy cores if possible, distributed between: Pathology (diagnosis, mandatory) Molecular sequencing (WES + RNA-seq) Biobank (-80C, for the future) Vaccine/functional testing (if already planned) Important You cannot do biobanking retroactively. Once tissue has been processed as FFPE only or discarded, the option disappears. Discuss before the intervention, not after. Ask your oncologist or surgeon: \u0026ldquo;Can you also preserve frozen tissue at -80C for future research?\u0026rdquo; ROSE evaluation ROSE (Rapid On-Site Evaluation) means that a pathologist verifies during the procedure whether the biopsy fragments contain viable tumor cells. Without ROSE, you risk freezing tissue that does not contain tumor.\nNot all centers offer ROSE. Ask specifically whether it is available.\nHow to access these options Many of the options described in this article are not available through the standard pathway (oncologist prescription, pharmacy). But that does not mean they are inaccessible. Specific legal mechanisms exist.\nClinical trials The most direct access to new treatments. Treatment is free, monitoring is intensive, and you contribute to advancing knowledge.\nWhere to search:\nClinicalTrials.gov \u0026ndash; search \u0026ldquo;RET fusion NSCLC\u0026rdquo; EU Clinical Trials Register LUNGevity Foundation \u0026ndash; LungMATCH navigator RETpositive.org \u0026ndash; RET-specific database Practical tip: You can be pre-screened for a trial without being eligible today. The relationship with the research center is established before you need it.\nCompassionate use / expanded access New medications that are not yet approved can be accessed for individual patients:\nExpanded Access (USA): FDA Form 3926, approval rate \u0026gt;99%, processing in 48h Heilversuch (Germany): Individual compassionate use procedure, legal basis Sec. 34 StGB. Covers vaccines, experimental drugs, and off-label combinations Named Patient Programs (EU): Through platforms like everyone.org (11,000+ patients served, 100% confirmed delivery) S2 form (EU Cross-Border Healthcare Directive) If you are insured in the EU, you can receive medical treatment in another member state with health insurance authorization. The S2 form (or E112) covers:\nConsultations and second opinions Procedures (cryoablation, biopsy) at specialized centers Treatment that is not available or has excessive waiting times in your country The process: Your oncologist completes the medical justification -\u0026gt; the health insurance body approves -\u0026gt; the external center bills the insurance body, not the patient.\nOff-label (outside indication) Medications approved for another indication, used based on scientific evidence for your situation. Examples: ANKTIVA (EC approved for bladder cancer, used off-label for NSCLC).\nRequires a prescription from the oncologist + documented medical justification.\nTimeline: what is available and when Available NOW 1-2 years 3-5 years Selpercatinib (standard) EP0031 (anticipated approval) Anti-RET PROTACs SBRT / Cryoablation Personalized RET-specific mRNA vaccines Molecular glues targeting fusions ctDNA monitoring (Signatera, Haystack) SY-5007 (anticipated approval) 3rd generation immunotherapies Drug repurposing (aspirin, statins) New ADCs (BL-B01D1, HER3-DXd) Vaccines targeting B cells + T cells FusionVAC (compassionate use) APS03118 (broad spectrum) Anti-RET cellular therapy (TCR-T) CeGaT CancerNeo (compassionate use) ANKTIVA + vaccine combo trials ANKTIVA (off-label EU) Tedopi/OSE2101 (after approval) IOZK IO-VAC (commercial) Organoids / functional testing BNT116, V940 (clinical trials) Resources RET-specific communities RETpositive.org \u0026ndash; patient community, clinical trials, registries The Happy Lungs Project \u0026ndash; research updates, webinars RET Renegades (Facebook) \u0026ndash; support group LUNGevity Foundation \u0026ndash; LungMATCH navigator, communities Cancer GRACE \u0026ndash; forum for RET+ patients Clinical trial databases ClinicalTrials.gov \u0026ndash; global database EU Clinical Trials Register \u0026ndash; European trials Reference centers for RET+ NSCLC Memorial Sloan Kettering (New York) \u0026ndash; Dr. Alexander Drilon, the world\u0026rsquo;s largest RET registry Gustave Roussy (Paris) \u0026ndash; the largest oncology center in Europe, active RET research programs MD Anderson (Houston) \u0026ndash; Dr. Vivek Subbiah, RET combination research IEO Milan \u0026ndash; real-world experience with RET+ in a European context What to do now Request complete molecular profiling (WES + RNA-seq) if you have not already been tested beyond the standard NGS panel Discuss ctDNA monitoring with your oncologist \u0026ndash; integrate it into the surveillance plan Ask about consolidative local therapy (SBRT/cryoablation) if you have residual lesions Explore eligibility for clinical trials with vaccines or next-generation RET inhibitors At every future biopsy, request biobanking \u0026ndash; frozen tissue at -80C in addition to standard FFPE Prepare your backup plan \u0026ndash; discuss pre-screening for trials with EP0031 or vepafestinib Discuss these options with your oncologist \u0026ndash; come prepared with specific questions for your next consultation The content of this article is for informational purposes only and does not constitute medical advice. Discuss any medical decision with your oncologist. If you have urgent symptoms, contact a doctor immediately. ","permalink":"https://oncoguide.github.io/en/cancer-types/lung-ret-fusion-proactive-strategy/","summary":"\u003cp\u003e\u003cstrong\u003eIf you are reading this, it means you have made it through the first few months.\u003c/strong\u003e You have the diagnosis, you have the treatment, you understand the basics. Selpercatinib is working \u0026ndash; the tumor has probably shrunk, you probably feel better than you expected.\u003c/p\u003e\n\u003cp\u003eAnd yet, the question that never goes away: \u003cstrong\u003ehow long will it last?\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis guide is for you. Not to scare you, but to show you that there are options your oncologist does not always mention \u0026ndash; not because they are irrelevant, but because they are new, specialized, and not (yet) part of standard protocols. Your oncologist remains the central piece of your treatment. This guide gives you the tools to have a more informed conversation with them.\u003c/p\u003e","title":"RET Fusion Lung Cancer: Proactive Strategy -- Beyond Standard Treatment"},{"content":"Our mission OncoGuide exists for a simple reason: no one should have to navigate a cancer diagnosis without clear, accurate, and accessible information.\nWhen you are diagnosed with cancer, the world stops. Then comes an avalanche of medical terms, urgent decisions, and conflicting information from across the internet. We have been through it. We know how overwhelming it is.\nThat is why we created this guide: a place where medical information is explained in plain language, grounded in scientific evidence, free of advertising and commercial interests. Free. Always.\nWhy anonymous? This project is not about who writes. It is about who reads.\nWe choose to remain anonymous because the message matters more than the messenger. We do not want our personal story to distract from the real purpose: providing useful, verified, and easy-to-understand information.\nAnonymity also allows us to write freely, without external pressure.\nWho writes this? OncoGuide is written by a cancer patient who has been through the diagnostic journey \u0026ndash; from first symptoms, through investigations, biopsy, diagnosis, and treatment decisions.\nWe are not doctors. We do not replace medical advice. But we know what it means to be a patient searching desperately for answers at 2 in the morning.\nEverything we publish is documented from authoritative medical sources: ESMO and NCCN clinical guidelines, peer-reviewed publications, and official healthcare system resources.\nHow you can help Are you a patient or caregiver? Share your experience. What information were you missing at the time of diagnosis? What do you wish you had known sooner? Flag errors. If you find inaccurate or incomplete information, let us know. Spread the word. If an article helped you, it might help someone else too. Are you a medical professional? Review our content. We need expert eyes. If you spot inaccuracies or information that needs updating, please write to us. Suggest topics. What questions do your patients ask most often? What could we explain better? Collaborate. If you would like to contribute articles or reviews, we welcome you. Contact You can reach us any time at: nog.opt.3o@icloud.com\nWe read every message. We reply whenever we can. We appreciate every suggestion.\nOncoGuide is an independent, non-commercial project, created by patients, for patients.\nThe content of this article is for informational purposes only and does not constitute medical advice. Discuss any medical decision with your oncologist. If you have urgent symptoms, contact a doctor immediately. ","permalink":"https://oncoguide.github.io/en/about/","summary":"Who we are, why we exist, and how you can contribute to OncoGuide.","title":"About OncoGuide"},{"content":"We\u0026rsquo;d love to hear from you OncoGuide is a project created by a patient, for patients. Every message matters to us.\nYou can write to us at: nog.opt.3o@icloud.com\nGeneral questions or feedback Have a question about the content on this site? Want to tell us what was helpful or what could be improved?\nWe\u0026rsquo;d love to hear from you. Write to us anytime at the address above.\nAre you a medical professional who wants to contribute? If you are a doctor, pharmacist, nurse, or other healthcare professional and would like to help review or improve our articles, we warmly invite you to get in touch.\nEvery professional contribution makes the information safer for patients.\nFound an error or outdated information? We do our best to keep information accurate and up to date, but medicine evolves rapidly.\nIf you notice something that is no longer accurate or an error of any kind, please let us know. You\u0026rsquo;ll be helping us and everyone who reads this guide.\nAre you from outside Romania? We would be very interested to learn how patient rights and treatment access work in your country.\nYour experience could help other patients around the world. Write to us and share your story.\nImportant note: We do not provide individual medical advice. The information on this site is educational and does not replace consultation with your doctor. For any medical decision, please speak with your treatment team.\nThe content of this article is for informational purposes only and does not constitute medical advice. Discuss any medical decision with your oncologist. If you have urgent symptoms, contact a doctor immediately. ","permalink":"https://oncoguide.github.io/en/contact/","summary":"Reach out with questions, suggestions, or to collaborate","title":"Contact"}]