Adult BI-RADS Malignancy Estimates Overpredict Cancer Risk in Pediatric Breast Lesions.

Adult-derived BI-RADS malignancy estimates may overestimate malignancy risk in pediatric breast lesions and contribute to unnecessary procedures. Pediatric breast cancer is exceedingly rare, yet BI-RADS malignancy estimates, developed for adults, are frequently applied to pediatric patients despite lacking validation. We retrospectively reviewed patients <20 years old who underwent breast lesion excision at a single institution from 2018 to 2025 (N = 279); 217 had preoperative BI-RADS scores. Fibroadenomas accounted for 87% of lesions (n = 263), and no malignancies were identified. Among patients with multiple lesions (n = 44), 97.7% had at least one fibroadenoma. Despite overwhelmingly benign pathology, 55% of patients were assigned BI-RADS 4 and 15.4% BI-RADS 3. The discordance between adult-derived BI-RADS malignancy estimates and observed pathology suggests these estimates overpredict malignancy risk in pediatric patients and may contribute to avoidable surgical excision and anxiety. These findings support development of pediatric-specific risk stratification tools.