Risk-reducing surgeries for breast cancer in Brazilian patients undergoing multigene germline panel: impact of results on decision making.

Purpose: To assess the behavior change of high-risk breast cancer patients regarding the intention to undergo risk-reducing mastectomies (RRM) before and after genetic testing results and to identify the main influencing factors in decision-making.

Methods: Prospective cohort study conducted between November 2021 and October 2022 with women under follow-up at the high-risk outpatient clinic of the State University of Campinas (UNICAMP). Patients were referred for genetic testing, followed by counseling according to the test result.