Study Sets Tumor-First BRCA Testing Against Germline-Guided Strategy in Ovarian Cancer

In JCO Precision Oncology, University of British Columbia and BC Cancer researchers explore testing strategies for uncovering pathogenic or likely pathogenic BRCA1 or BRCA2 gene variants in ovarian cancer patients — results that can help guide the use of PARP inhibitor drugs such as olaparib. The team compared the so-called "ASCO strategy" — an American Society of Clinical Oncology-recommended approach that involves germline testing on BRCA1/2 and other risk genes followed by somatic testing in cases without inherited pathogenic variants — with tumor-first "triage" approach to testing for BRCA1/2 alterations. The team's modeling analyses suggest that tumor-first testing is more cost-effective, though the germline- and tumor-based approach would be expected to uncover more pathogenic variants when large numbers of epithelial ovarian cancer patients are tested each year. Overall, the authors conclude that "the strategy of germline testing first, followed by tumor testing … has the potential to identify the highest number of individuals with BRCA [pathogenic variants]," though "this is not a cost-effective strategy, and it relies on a high proportion of patients with ovarian cancer having germline testing at initial diagnosis.