- A review and expert opinion offers guidance on treating microsatellite instability-H (MSI-H)/deficient DNA mismatch repair (dMMR) tumors, treatment intensification, and combination treatment for metastatic colorectal cancer (mCRC).
Why this matters
- There has been significant progress recently in improving response rates in BRAFV600E mCRC, which responds poorly to standard chemotherapy.
- All patients with mCRC should be tested with a tumor mutation panel that includes RAS and BRAF.
- MSI-H or MSI-H/dMMR tumors, regardless of BRAFV600E status, should be treated with immunotherapy, which has been shown to result in high and durable response.
- Patients with BRAFV600E mCRC and favorable performance status can be considered for intensified treatment with FOLFOXIRI (irinotecan, oxaliplatin, fluorouracil, folinate) + bevacizumab.
- A 3-pronged approach, consisting of an epidermal growth factor receptor (EGFR) inhibitor, BRAF inhibitor, and MEK inhibitor, is effective in patients with BRAFV600E mCRC.
- The optimal treatment strategy to avoid acquired drug resistance has not yet been determined.
- Expert opinion.