Real-world BRAF testing patterns for patients with metastatic colorectal cancer (mCRC), metastatic melanoma, and non-small cell lung cancer (NSCLC).

Abstract

e18778 Background: BRAF mutations are estimated to occur in up to 10% of people with colorectal cancer, 45% with melanoma, and 2-4% with NSCLC and generally represent a poor prognosis for these patients. The National Comprehensive Cancer Network (NCCN) recommends BRAF testing for patients with mCRC, melanoma and NSCLC, however adherence to guidelines and real-world testing rates are not well known. This study describes real-world BRAF testing rates among mCRC, m-melanoma and NSCLC patients. Methods: We performed a retrospective study of adult patients diagnosed with mCRC or m-melanoma from 1/2013 to 11/2020 in the nationwide Flatiron Health EHR-derived de-identified database and with NSCLC from 1/2013 to 11/2020 in the ConcertAI Definitive Oncology Dataset. We measured the proportion of patients receiving a BRAF test and timing of testing in relation to diagnosis and treatment line, concentrating the latter on a limited time frame when there was a stable period of testing (2018-2019 for mCRC and m-melanoma; 2018 for NSCLC). Results: We included 21,758 patients with mCRC, 4,276 patients with m-melanoma, and 12,236 patients with NSCLC of whom 52.7%, 92.0% and 17.2%, respectively, received a BRAF test. Testing rates for mCRC and NSCLC increased over time (mCRC: 27.3% in 2013, 49.9% in 2016, 71.4% in 2020; NSCLC: 6.4% in 2013, 13.5% in 2016 and 29.5% in 2018) and were relatively stable for m-melanoma (94.5% in 2013, 90.6% in 2016, 89.5% in 2020). Among BRAF-tested mCRC patients in 2018-2019 (70.3%, n=5,874), 7.8% were tested before metastatic (m-) diagnosis, with median time from test to m-diagnosis of 8.5 months; 32.1% on or after m-diagnosis and before 1L and 55.8% on or after 1L, with median time from m-diagnosis to test of 1.4 months. Among BRAF-tested m-melanoma patients in 2018-2019 (91.7%, n=1,174), 31.0% were tested before m-diagnosis, with median time from test to m-diagnosis of 9.5 months; 62.2% on or after m-diagnosis and before 1L and 2.5% on or after 1L, with median time from m-diagnosis to test of 0.0 months. Among BRAF-tested NSCLC patients in 2018 (29.5%, n=2,010), 3.0% were tested before earliest diagnosis, with median time from test to diagnosis of 0.3 months; 24.6% on or after earliest diagnosis and before 1L and 15.4% on or after 1L, with median time from diagnosis to test of 1.1 months. (For about 60% of the BRAF-tested patients, it was not possible to identify at which stage of treatment the test was conducted). Conclusions: BRAF testing rates were highest among m-melanoma patients, followed by mCRC and NSCLC. Testing rates for mCRC and NSCLC increased from 2013 to 2020, which may have been in response to guideline changes and availability of targeted treatments. The majority of BRAF testing occurred before 1L in melanoma and NSCLC, and on or after 1L in mCRC.