A multicenter survey on BRAF screening for the implementation of perioperative cancer genomic medicine for resectable colorectal oligometastases.

BACKGROUND

Genomic screening is an essential, but potentially time-consuming procedure, especially in neoadjuvant settings. We evaluated the preoperative screening of the BRAF V600E mutation for recruitment to a clinical trial among patients with resectable colorectal oligometastases (CRM).

METHODS

In April 2022, an investigator-initiated trial was launched to investigate the efficacy and safety of perioperative use of the BEACON triplet regimen for BRAF V600E mutant resectable CRM. BRAF screening was retrospectively conducted in patients with resected colorectal liver metastases in 2019 for planning the trial and prospectively conducted in preoperative patients with resectable CRM from January 2022 to June 2025 for patient recruitment to the trial.

RESULTS

BRAF V600E mutation was detected in 12 (3.2%) of 379 postoperative patients retrospectively and in 36 (1.7%) of 2140 preoperative patients prospectively, with 1840 patients (86.0%) carrying the wild-type and 264 patients (12.3%) classified as untested. The detection rate of the BRAF V600E mutation was significantly lower when the screening was performed prospectively in preoperative patients (P < 0.001). The untested rates varied across metastatic organs, with 10.3% in the liver, 18.1% in the lungs, 12.0% in the lymph nodes, 16.7% in the peritoneum, and 7.8% in other organs. The untested rates decreased consistently across semiannual comparisons: 28.5% in the first evaluation, followed by 15.0%, 12.0%, 8.4%, 9.1%, 7.3%, and 7.1% (P < 0.01 when compared with the first period).

CONCLUSION

Raising physician awareness, as reflected by the untested rate, is a crucial factor in conducting clinical trials to implement perioperative cancer genomic medicine.