HealthDay News — According to a study published in JAMA Oncology, African-American (AA) identity is associated with increased risk of triple-negative breast cancer (TNBC) among women with a prior diagnosis of benign breast disease (BBD).
In a retrospective analysis of data from a cohort of 2588 AA and 3566 white American (WA) women with a biopsy-proven BBD diagnosis, Lisa Newman, MD, MPH, from the Henry Ford Health System in Detroit, and colleagues examined whether AA identity is associated with TNBC among women with a prior diagnosis of BBD.
The researchers found that 4.1% of AA patients (mean follow-up interval, 6.8 years) and 4.0% of WA patients (mean follow-up interval, 6.1 years) developed subsequent breast cancers.
In each subset, more than three-quarters of subsequent breast cancers were DCIS or stage I. The 10-year probability estimate for developing TNBC was 0.56% (95% confidence interval, 0.32 to 1.0%) and 0.25% (95% confidence interval, 0.12 to 0.53%) for AA and WA patients, respectively.
Among AA patients who developed subsequent invasive breast cancers, 16 of 66 developed TNBC, compared with 7 of 94 of the WA patients who developed subsequent invasive breast cancers and had complete biomarker data (24.2 versus 7.4%; P=.01).
“This study is the largest analysis to date of TNBC in the context of racial/ethnic identity and BBD as risk factors,” the authors write. “This finding suggests that AA identity is associated with inherent susceptibility for TNBC pathogenetic pathways.”
Newman LA, et al. “Association Between Benign Breast Disease in African American and White American Women and Subsequent Triple-Negative Breast Cancer.” JAMA Oncol. 2016. doi:10.1001/jamaoncol.2016.5598. [Epub ahead of print]