A Closer Look at Breast Cancer Risk Across Benign Breast Diagnoses
A new Breast Cancer Surveillance Consortium (BCSC) study finds that future breast cancer risk varies widely across specific benign breast disease diagnoses, even among diagnoses commonly grouped into the same broad histologic categories.
Benign breast disease (BBD) includes a wide range of noncancerous findings diagnosed after a breast biopsy. Although BBD is associated with future breast cancer risk, diagnoses are often grouped into broad histologic categories when studying risk. Previous studies have examined risks associated with some specific diagnoses, but modest sample sizes for individual diagnoses have made it difficult to evaluate a wide range of BBDs.
A new study from the Breast Cancer Surveillance Consortium (BCSC), published in Cancer Epidemiology, Biomarkers & Prevention, examined associations between 38 specific BBD diagnoses and subsequent invasive breast cancer and ductal carcinoma in situ (DCIS). The study included 131,075 benign breast biopsy episodes from eight BCSC registries between 1994 and 2022. For comparison, researchers also included nearly 1.6 million negative screening mammograms among women without a prior breast biopsy.
Breast cancer risk varied substantially across specific BBD diagnoses. LCIS was associated with the greatest increases in risk, with a 5.6-fold increased risk of invasive breast cancer and an 8.8-fold increased risk of DCIS. Proliferative lesions with atypia were consistently associated with higher risk, although the magnitude varied across specific diagnoses, with 2.8- to 4.9-fold increased risks of invasive breast cancer and 5.1- to 8.5-fold increased risks of DCIS. Importantly, variation among individual diagnoses was also apparent within the lower-risk histologic categories. Among proliferative lesions without atypia, for example, associations with invasive breast cancer ranged from little or no increased risk for papillomatosis to a 1.6-fold increased risk for usual ductal hyperplasia and a 2.8-fold increased risk for multiple papillomas. Variation was also observed among nonproliferative diagnoses, which generally showed weaker associations with breast cancer risk.
Most associations also decreased with increasing time since biopsy, indicating that both the specific BBD diagnosis and the amount of time that has passed since diagnosis may be informative when assessing future breast cancer risk.
These findings highlight how broad histologic categories can mask meaningful differences in breast cancer risk across individual benign breast diagnoses. Incorporating more detailed information about specific BBD diagnoses may help improve breast cancer risk prediction and support more individualized approaches to screening and prevention.
Sattayapiwat O, Weaver DL, Borowsky AD, et al. Advancing Evidence of the Associations between Specific Benign Breast Diagnoses and Future Breast Cancer Risk. Cancer Epidemiol Biomarkers Prev. 2026. doi:10.1158/1055-9965.EPI-26-0640. [link]
The full article can be found here: