Model for Predicting Breast Cancer Risk in Women With Atypical Hyperplasia.
Level 3 - non-randomized controlled study
Retrospective cohort study developing and validating a prognostic prediction model
PubMed 29676945 · doi:10.1200/JCO.2017.75.9480
What was done
The authors developed and externally validated a breast cancer (BC) risk prediction model (AH-BC) tailored for women aged 18 to 85 years with pathologically confirmed benign atypical hyperplasia (AH). Retrospective cohorts from Rochester, MN (model derivation) and Nashville, TN (external validation) were analyzed. Clinical risk factors and histologic features were selected using L1-penalized Cox proportional hazards regression and modeled using Fine and Gray competing risk regression (accounting for death). Discrimination and calibration were assessed at 10 years.
What was found
The derivation cohort included 699 women (142 developed BC; median follow-up 8.1 years) and the external validation cohort included 461 women (114 developed BC; median follow-up 11.4 years). The final model retained three variables: age at biopsy, age at biopsy squared, and number of foci of AH. At 10 years, the model achieved a discrimination of 0.63 (95% CI, 0.57 to 0.70) and calibration of 0.87 (95% CI, 0.66 to 1.24) in the development set. In external validation, discrimination was 0.59 (95% CI, 0.51 to 0.67) and calibration was 0.91 (95% CI, 0.65 to 1.42).
Why it matters
Standard breast cancer risk models lack accuracy for women with atypical hyperplasia. This model provides an individualized 10-year risk estimate using easily accessible variables: age at biopsy and the number of AH foci.
Limits
The study is retrospective. Discrimination in the external validation cohort was modest (concordance index 0.59 with lower CI 0.51). The abstract does not report patient racial/ethnic demographics or account for subsequent chemoprevention or risk-reducing surgeries.
Cited by
- supports A breast biopsy showing atypia significantly increases a woman's lifetime risk of developing breast cancer.