Treatment of metastatic colorectal cancer with BRAF V600E mutation: A multicenter real-world study in China

Abstract

Background: BRAF V600E mutant-metastatic colorectal cancer (mCRC) is characterized by its short survival time. Treatment approaches vary depending on whether or not the metastases are initially resectable. The benefit of metastasectomy remains unclear, and the optimal first-line treatment is controversial. This study aimed to describe the prognosis of BRAF V600E mutant-mCRC, analyze the recurrence pattern in resectable patients, and explore the optimal first-line treatment for unresectable patients.

Methods: Patients diagnosed with BRAF V600E mutant-mCRC between February 2014 and January 2022 in five hospitals were enrolled. Date on clinical and pathological characteristics, treatment features, and survival outcomes were collected.

Results: Of the 220 included patients, 64 initially resectable patients had a significantly longer overall survival (OS) (37.07 vs. 20.20 months, P < 0.001) than initially unresectable patients. Of 156 unresectable patients, 54 received doublet (FOLFOX, XELOX or FOLFIRI) or triplet (FOLFOXIRI) chemotherapies (Chemo), 55 received Chemo plus Bevacizumab (Chemo+Bev), and 33 received vemurafenib plus cetuximab and irinotecan (VIC). The VIC regimen had a better progression-free survival (PFS) (12.70 months) than the Chemo (6.70 months, P < 0.001) and Chemo+Bev (8.8 months, P = 0.044) regimens. Patients treated with VIC had the best overall response rate (60.16%, P < 0.001), disease control rate (93.94%, P < 0.001) and conversional resection rate (24.24%, P = 0.003).

Conclusions: Metastasectomy is beneficial to the survival of patients with BRAF V600E mutant-mCRC. For initially unresectable patients, VIC as first-line therapy is associated with a better prognosis and efficacy than doublet and triplet chemotherapy with or without bevacizumab.

Keywords: BRAF V600E mutation; First-line therapy; Metastasectomy; Metastatic colorectal cancer; VIC.