Comparing Breast Cancer and Cardiovascular Disease Risk and Use of Chemoprevention and Statins among Women with High-risk Breast Lesions

Breast cancer chemoprevention with selective estrogen receptor modulators (SERM) or aromatase inhibitors (AI) remains underutilized among high-risk women. A potential barrier to chemoprevention is competing comorbidities such as atherosclerotic cardiovascular disease (ASCVD), due to concern for additional medication side effects. We conducted a retrospective cohort study among women with atypical hyperplasia (AH) or lobular carcinoma in situ (LCIS), an important target population for chemoprevention. We compared risks for breast cancer and ASCVD, as well as use of SERMs/AIs versus statins among high-risk women (defined as a 5-year invasive breast cancer risk >= 1.67% and 10-year ASCVD risk >= 7.5%, respectively). We used clinical data extracted from the electronic health record to calculate breast cancer risk according to the Breast Cancer Surveillance Consortium model and ASCVD risk according to the 2013 American College of Cardiology/American Heart Association risk calculator. Among 298 evaluable women, mean age was 58.2 years (SD, 8.34), with 33% non-Hispanic White, 41% Hispanic, 9% non-Hispanic Black, 6% Asian, and 11% other/unknown race/ethnicity. About 98% of women met high-risk criteria for breast cancer, whereas 30% were high-risk for ASCVD. Mean 10-year risk of breast cancer was higher than mean 10-year risk of ASCVD (9.14% vs. 6.69%; P < 0.001). Among women who met high-risk criteria for both diseases, use of statins was higher compared with SERMs/AIs (58% vs. 21%; P < 0.001). Among women with AH or LCIS, statin use was higher compared with breast cancer chemoprevention among eligible women, despite having a higher mean risk of breast cancer than ASCVD.