EGFR-Inhibitor Therapy for non-V600E BRAF-Mutant Colorectal Cancer

BRAF V600E mutation is a rare but adverse prognostic factor in metastatic colorectal cancer (mCRC) that confers resistance to EGFR-targeted agents. Up to 25% of BRAF mutations are non-V600E and are categorized as class 2 (kinase-activating and RAS-independent) or class 3 (kinase-impaired and RAS-dependent).

Investigators have now conducted a retrospective, multicenter study to characterize the response to anti-EGFR agents according to BRAF mutation functional class among 40 patients with non-V600E BRAF-mutant mCRC. Of these patients, 30% had class 2 mutations and 70% had class 3 mutations.

Response to anti-EGFR therapy was observed in 50% of patients with class 3 mutations and in 8% of patients with class 2 mutations. Responses were seen with…