The first 60 days: BRAF V600E-mutant colorectal cancer
BRAF V600E bowel cancer carries the same mutation as many melanomas, but BRAF drugs alone did nothing here because the tumour re-routes its growth signal through EGFR. Blocking both with encorafenib and cetuximab, now given with chemotherapy from the start, has doubled survival in a subtype that used to be the worst. Below, week by week, is what OnCo's record of BRAF V600E-mutant colorectal cancer says about the first two months: the order is typical, the timing is yours to ask about. Sections appear only where the record has something to say. Orientation, not medical advice.
What happens now
Staging tests establish exactly what and where the cancer is. Everything else follows from the answers.
Ask which of these were tested and what the results were; see the report reader for what each value means.
These specialties appear in the standard of care for this cancer. In most centres they meet weekly as a tumour board to agree each plan; you can ask when yours was discussed and what was decided.
- SurgeonNamed in the standard of care for: Localised.
- Medical oncologistNamed in the standard of care for: Metastatic, microsatellite-stable, first line, Metastatic, previously treated, Metastatic, mismatch-repair deficient, Localised.
A second opinion from a centre that treats many similar cases is normal, not rude; the standard of care tells you what to compare it against.
Each row is a setting from the standard of care, in the order it usually arises. Not all will apply to you; your stage and biomarkers decide which do. The guideline grade, where recorded, says how strong the evidence is.
Surgery and stage-based adjuvant FOLFOX or CAPOX as for colorectal cancer; BRAF status does not yet change adjuvant treatment outside trials.
Encorafenib plus cetuximab plus mFOLFOX6 (BREAKWATER); encorafenib plus cetuximab alone for patients unfit for chemotherapy.
Checkpoint blockade first (pembrolizumab, or nivolumab plus ipilimumab); BRAF-targeted therapy at progression.
Encorafenib plus cetuximab (BEACON CRC) if not already given; then trifluridine-tipiracil with bevacizumab, fruquintinib or regorafenib.
Generated from this cancer's standard of care, biomarkers and open problems. Take the group that matches where you are. To tick, add your own and print, open the one-page appointment sheet.
Newly diagnosed
- What is my exact diagnosis, stage, and grade, and which tests established them?Everything else follows from an accurate stage and subtype.
- Which biomarkers have been tested on my tumour (for example BRAF V600E by sequencing or VE1 immunohistochemistry, Mismatch repair status, RAS wild-type by definition; co-mutations rare, Consensus molecular subtype 1 enrichment, Circulating tumour DNA to track MAPK reactivation on treatment), and what were the results?These results decide eligibility for targeted therapy, immunotherapy, and trials.
- Which subtype is my cancer, and does that change the recommended treatment?Recognised subtypes for this cancer include BRAF V600E, microsatellite-stable, BRAF V600E with mismatch-repair deficiency, BRAF non-V600mutations, a distinct and less aggressive group.
- Is germline (inherited) genetic testing recommended for me or my family?Inherited variants can change treatment and matter for relatives.
Metastatic, microsatellite-stable, first line
- For my situation (metastatic, microsatellite-stable, first line), which of the standard options do you recommend and why?Guideline options include: Encorafenib plus cetuximab plus mFOLFOX6 (BREAKWATER); encorafenib plus cetuximab alone for patients unfit for chemotherapy.
- Am I a candidate for Encorafenib, Cetuximab, FOLFOX (5-FU, leucovorin, oxaliplatin), and what side effects should I expect?Knowing the expected toxicities helps you plan work, family, and supportive care.
- How do the results of BREAKWATER apply to someone like me?Trial populations differ from individual patients; ask how closely you match.
Metastatic, previously treated
- For my situation (metastatic, previously treated), which of the standard options do you recommend and why?Guideline options include: Encorafenib plus cetuximab (BEACON CRC) if not already given; then trifluridine-tipiracil with bevacizumab, fruquintinib or regorafenib.
- Am I a candidate for Encorafenib, Cetuximab, Trifluridine/tipiracil or related drugs, and what side effects should I expect?Knowing the expected toxicities helps you plan work, family, and supportive care.
- How do the results of BEACON CRC apply to someone like me?Trial populations differ from individual patients; ask how closely you match.
Metastatic, mismatch-repair deficient
- For my situation (metastatic, mismatch-repair deficient), which of the standard options do you recommend and why?Guideline options include: Checkpoint blockade first (pembrolizumab, or nivolumab plus ipilimumab); BRAF-targeted therapy at progression.
- Am I a candidate for Pembrolizumab, Nivolumab, Ipilimumab, and what side effects should I expect?Knowing the expected toxicities helps you plan work, family, and supportive care.
- How do the results of KEYNOTE-177 and CheckMate 8HW apply to someone like me?Trial populations differ from individual patients; ask how closely you match.
Localised
- For my situation (localised), which of the standard options do you recommend and why?Guideline options include: Surgery and stage-based adjuvant FOLFOX or CAPOX as for colorectal cancer; BRAF status does not yet change adjuvant treatment outside trials.
- Am I a candidate for FOLFOX (5-FU, leucovorin, oxaliplatin), CAPOX (capecitabine, oxaliplatin), Oxaliplatin, and what side effects should I expect?Knowing the expected toxicities helps you plan work, family, and supportive care.
Any stage
- Are there clinical trials I could join, for example of A Study of Encorafenib Plus Cetuximab Taken Together With Pembrolizumab Compared to Pembrolizumab Alone in People With Previously Untreated Metastatic, Efficacy and Safety of Tunlametinib Plus Vemurafenib in Patients With BRAF V600E-mutant Metastatic Colorectal Cancer, BREAKWATER, Encorafenib?Trials are how the next standard of care is set; asking early keeps options open.
- Would a second opinion at a high-volume centre change anything, and can you help arrange it?Rare or high-stakes decisions benefit from a centre that treats many similar patients.
- What supportive care (symptom control, nutrition, exercise, mental health, financial help) is available from the start?Supportive care improves quality of life and helps patients complete treatment.
- I read that “No standard therapy after progression on encorafenib and cetuximab”. How does that affect my plan?Open problems are where trials and second opinions matter most.
- I read that “Resistance through MAPK reactivation and MET amplification is common and untargeted”. How does that affect my plan?Open problems are where trials and second opinions matter most.
Trials open now for this cancer in OnCo, largest phase first. Joining a trial is a decision like any other: ask what the comparison arm is, whether a placebo is used, and what happens if you leave. The cancer page searches ClinicalTrials.gov live for more.
- Efficacy and Safety of Tunlametinib Plus Vemurafenib in Patients With BRAF V600E-mutant Metastatic Colorectal CancerPhase 3 · recruiting · NCT06008119A Multicenter, Randomized, Open-label, Phase 3 Study to Evaluate the Efficacy and Safety of Tunlametinib Plus Vemurafenib in Patients With BRAF V600E-mutant Metastatic Colorectal Cancer
- A Study of Encorafenib Plus Cetuximab Taken Together With Pembrolizumab Compared to Pembrolizumab Alone in People With Previously Untreated MetastaticPhase 2 · active · NCT05217446A PHASE 2, RANDOMIZED, OPEN-LABEL STUDY OF ENCORAFENIB AND CETUXIMAB PLUS PEMBROLIZUMAB VERSUS PEMBROLIZUMAB ALONE IN PARTICIPANTS WITH PREVIOUSLY UNTREATED BRAF V600E-MUTANT, MSI H/DMMR METASTATIC COLORECTAL CANCER
Much of what helps in the first weeks is free if you know to ask: testing, helplines, rides and lodging, second opinions, trial travel.
- BRAF V600E-mutant colorectal cancer: the full pageBRAF V600E bowel cancer carries the same mutation as many melanomas, but BRAF drugs alone did nothing here because the tumour re-routes its growth signal through EGFR. Blocking both with encorafenib and cetuximab, now given with chemotherapy from the start, has doubled survival in a subtype that used to be the worst.
- One-page appointment sheetYour questions, the words you may hear, what to bring, and space for the answers. Print it.
- Treatment sequencingWhich treatment tends to follow which, line by line.
- NavigatorStandard of care for your stage, what you have tried, and trials near you.
- Consensus molecular subtypes (CMS1-4): The consensus molecular subtypes are four gene-expression groups of bowel cancer: immune (CMS1), canonical (CMS2), metabolic (CMS3), and mesenchymal (CMS4), with different prognoses.
- Sidedness (left vs right colon): Where in the colon a tumour starts changes its biology and which drugs work.
- Circulating tumour DNA (ctDNA): Circulating tumour DNA (ctDNA) consists of fragments of DNA shed by tumour cells into the blood, detectable with sensitive sequencing.
- Microsatellite instability (MSI-H) / mismatch repair deficiency (dMMR): Microsatellite instability is the mark of a broken DNA spell-checker (loss of MLH1, MSH2, MSH6 or PMS2) that leaves thousands of mutations, so the tumour displays abnormal proteins that T cells can recognise.
Every term links to the glossary.