SEER-based analysis of risk of contralateral breast cancer

Analysis of the SEER database found that among 812,851 women with unilateral breast cancer diagnosed between 1990 and 2015 who were followed for up to 25 years, the annual risk of contralateral breast cancer was 0.37% and the 25-year actuarial risk of contralateral invasive breast cancer was 9.9%. The 25-year actuarial risk was similar for DCIS (10.1%) and invasive breast cancer (9.9%) patients; it was higher for black women (12,7%) than for white women (9.7%), and it was lower for women with ER-positive breast cancer (9.5%) than for women with ER-negative breast cancer (11.2%).