A critical appraisal of the current landscape of resectable BRAF mutated colorectal liver metastases: a systematic review.

ABSTRACT

BACKGROUND: Patients with surgically resectable BRAF-mutated colorectal liver metastases (CRLM) or limited extrahepatic disease constitute a highly selective subgroup among BRAF-mutated patients, characterized by a more indolent disease biology. This is evident in their suitability for surgical resection. However, initial studies from a decade ago presented a discouraging outlook for these patients, citing early, frequent, multifocal recurrences and a very limited median overall survival (OS) of less than two years. Our objective was to provide an updated, comprehensive, and critically assessed review of the current literature on the prognostic impact of BRAF variants in CRLM, as well as to explore optimal treatment strategies for these patients through a systematic search. METHODS: A systematic literature search of the Medline, Scopus, and CENTRAL databases for studies reporting long-term outcomes of patients with a known BRAF status was performed. RESULTS: A total of 386 unique studies were screened during the study selection process. After applying the exclusion criteria, a total of 18 studies published between 2012 and 2023 were deemed eligible for inclusion. CONCLUSIONS: In contrast to older studies, more recent studies, with larger sample sizes, have revealed that the rate of extrahepatic recurrence is comparable between BRAF-mutated and wild-type patients. Furthermore, they have reported significantly improved survival outcomes, with OS extending up to 52 months. Notably, patients with non-V600E BRAF mutations may even achieve outcomes comparable to those with wild-type BRAF CRLM. Additionally, a few recent studies have compared surgery and systemic therapies, indicating that surgery is associated with improved survival rates, even for patients with the V600E mutation. This challenges the previous belief that BRAF mutations are absolute contraindications to surgical treatment. Surgical denial for technically resectable patients may now be reserved for specific clinical scenarios, such as the presence of a BRAF V600E mutation and concurrent extrahepatic disease.