Evaluating the Implementation and Impact of BRAF Reflex Mutation Testing in Melanoma, Lung, and Colorectal Cancers

Reflex molecular testing, the process of profiling specimens at diagnosis, is emerging in oncology, allowing for prompt therapy initiation, and potentially improving outcomes. This study evaluates the impact of reflex BRAF testing on treatment timelines and outcomes in melanoma, lung and colorectal cancers at the McGill University Health Center (MUHC).

A retrospective chart review was conducted at the MUHC. The study included patients with melanoma, lung, and colorectal cancers who underwent BRAF testing from 2017 to 2022. Data on demographics, cancer type, stage, test ordering specialist, testing method, and treatment outcomes were extracted. Statistical analyses included descriptive and multivariate regression analyses.

518 BRAF molecular tests were performed, with 173 patients meeting the inclusion criteria [median age 72 (IQR 60-80 years), 46.2% female]. Of these, 75.7% had melanoma, 23.7% colorectal cancer and 0.58% lung cancer. Pathologists ordered 71.1% of BRAF tests, primarily relying on immunohistochemistry. By 2022, all BRAF results were available before oncology consultations. Patients with pre-consultation BRAF results were more likely to receive targeted therapy (59.4% vs 36.4%). The availability of BRAF test results was associated with quicker treatment initiation and better alignment of therapy with mutation status.

This study underscores the success of the pathology team at MUHC in implementing reflex BRAF mutation testing, enhancing clinical care by ensuring the timely availability of test results. Delays in testing may adversely affect clinical decision-making and therapy selection, highlighting the need for standardized reflex testing protocols across Canada to optimize patient outcomes in melanoma, lung, and colorectal cancers.