168P Cardiovascular risks in breast cancer: Insights from BRCA1/2 mutation carriers and sporadic cases

Breast cancer (BC) survival has improved, but cancer therapy-related cardiovascular toxicity (CTR-CVT) remains a concern. While BRCA1/2 genes, involved in DNA repair, may offer cardiovascular protection, pathogenic variants in these genes could compromise this defense. This study examines cardiovascular disease (CVD) incidence in BC patients with BRCA1/2 mutations and sporadic BC cases, before and after BC diagnosis. A retrospective cohort study (1995-2020) in the Stockholm-Gotland region involved 522 BRCA1/2 mutation carriers with BC and 32,632 sporadic BC patients linked to population registers. Cardiovascular risk factors, events, and cancer treatments were assessed, using the general female population in Stockholm as a CVD incidence reference. BRCA1/2 mutation carriers, younger and often premenopausal at diagnosis, and sporadic BC patients were studied. Pre-BC diagnosis, 5.4% of carriers and 16.5% of sporadic patients had CV risk factors. Post-BC diagnosis, 25.9% of carriers and 33.4% of sporadic patients developed risk factors. Both groups experienced increased CV risk factors post-diagnosis. Pre-diagnosis, CVD incidence was lower in BRCA1/2 carriers but became similar post-diagnosis. The general female population had lower CVD incidence, indicating higher CVD risks in BC patients. BC patients, whether BRCA1/2 carriers or sporadic cases, face increased CVD risk post-diagnosis. The study underscores the need for cardiovascular surveillance. These findings support current guidelines advocating CVD screening for cancer patients.