Takayuki Yoshino

Patients with newly diagnosed metastatic colorectal cancer whose tumour carries a BRAF V600E mutation, which is about 8-12% of cases, should now be offered encorafenib and cetuximab together with FOLFOX from the start rather than after chemotherapy fails; median survival has roughly doubled to about two and a half years. BRAF testing at diagnosis is therefore essential, alongside RAS and mismatch repair testing. The regimen is more toxic than chemotherapy alone.

Combination checkpoint blockade became a first-line standard for mismatch repair-deficient metastatic colorectal cancer in 2025; the later all-lines comparison against nivolumab alone showed the CTLA-4 antibody adds to the PD-1 antibody, the first phase 3 to prove that in this disease.

The blood test stratifies risk far better than stage or pathology. It supports treating ctDNA-positive patients and suggests ctDNA-negative patients gain little from chemotherapy, but because treatment was not randomised the de-escalation claim needs the randomised trials that are now under way.

It is the proof that plasma genotyping can enrol patients for a targeted colorectal trial, which matters most for a 2 to 3% alteration where archival tissue is often exhausted or out of date.

The antibody-drug conjugate route into HER2-positive colorectal cancer, extended by DESTINY-CRC02 at a lower dose; interstitial lung disease is the class risk that defines how the drug is monitored.

Every colorectal cancer should be tested for mismatch repair deficiency, because patients whose metastatic tumour is dMMR should receive pembrolizumab rather than chemotherapy as first treatment, gaining a much better chance of durable remission with fewer side effects. About a third of dMMR tumours do not respond initially, so early scans are essential and chemotherapy remains available. The trial does not apply to the 95% of metastatic colorectal cancers that are mismatch-repair proficient (the deficient share is higher in localised disease, about 15%).

Encorafenib with cetuximab became the standard second-line treatment for BRAF V600E disease, and the platform BREAKWATER later moved into first line with chemotherapy added, doubling survival again.

The largest de-escalation exercise in adjuvant oncology, and the reason a patient with a T3 N1 colon cancer is now offered four cycles of CAPOX rather than twelve of FOLFOX, with a fraction of the neuropathy.