Women with atypical hyperplasia (AH) on breast biopsy have an aggregate increased risk of breast cancer (BC), but existing risk-prediction models do not provide accurate individualized estimates of risk in this subset of high-risk women. Here, Mayo Clinic researchers used the Mayo benign breast disease cohort to develop and validate a model of BC risk prediction that is specifically for women with AH, which we have designated as AH-BC. Retrospective cohorts of women age 18 to 85 years with pathologically confirmed benign AH from Rochester, Minnesota, and Nashville, Tennessee, were used for model development and external validation, respectively.
The model-building set consisted of 699 women with AH, 142 of whom developed BC, and the external validation set consisted of 461 women with 114 later BC events. The final AH-BC model included three covariates: age at biopsy, age at biopsy squared, and number of foci of AH.
Researchers created a new model with which to refine BC risk prediction for women with AH. The AH-BC model demonstrates good discrimination and calibration, and it validates in an external data set. The study was published in the Journal of Clinical Oncology.