Abstract A60: Second primary breast cancer incidence rates among black and white female breast cancer survivors

Abstract

Abstract Background: Breast cancer incidence increases with age and exhibits a Black-to-White incidence crossover around age 45. Breast cancer survivors are at a significantly elevated risk of developing a second primary breast compared with the general population. The purpose of this study was to determine whether a similar crossover occurs in second primary breast cancer incidence in Black and White women. Methods: The Surveillance, Epidemiology, and End Results’ Registry 9 was used to follow 415,664 White and 39,887 Black female breast cancer survivors, diagnosed at age 19 or older, for a second primary breast cancer between 1973 and 2007. Cumulative incidence curves, which account for the competing risk of death and the occurrence of second primary non-breast cancers, were generated; Pepe and Mori's test was used to test for significance. Results: A total of 22,290 (40.7%) second primary breast cancers were observed among 450,936 women who had survived 2 months or more after an in situ or invasive breast cancer. The majority, 18,227 (81.7%) cases, occurred in women diagnosed with a first primary breast cancer at age 45 or older. Second primary breast cancer followed the incidence pattern of the first primary breast cancer in Black and White women diagnosed before age 45. It was opposite of the pattern of first primary breast cancer in Black and White women diagnosed at age 45 or later. Despite the Black-to-White crossover of first primary breast cancer around age 45, the incidence of second primary breast cancer was higher in Blacks than in Whites. Citation Information: Cancer Epidemiol Biomarkers Prev 2011;20(10 Suppl):A60.