Pathologic findings of follow-up surgical excision for radial scar on breast core needle biopsy.

The data regarding radial scar (RS) as a risk factor for breast cancer are conflicting, and it is unclear whether an excision is warranted for patients with RS identified on core needle biopsy (CNB). In this study, we investigated the follow-up excisional results for patients with RS on CNB with no history of or concurrent breast cancer or atypical proliferative lesions. The study cohort was composed of 403 such cases, and follow-up excision (FUE) was performed in 220 (54.6%). There was no significant difference in the radiologic findings in cases with and without FUE. Of the 220 cases with FUE, only 2 (0.9%) were upgraded to malignancy (1 invasive carcinoma and 1 ductal carcinoma in situ), whereas 44 cases (20.0%) were upgraded to atypical ductal hyperplasia and 13 cases (5.9%) to lobular neoplasia. Upgrades were associated with greater age but not with any other variable. This is one of the largest studies to evaluate excisional findings in patients with RS identified on CNB but no history of or concurrent breast cancer or atypical proliferative lesions, and the extremely low malignancy-upgrade rate indicates that conservative follow-up with imaging rather than surgical excisions may be more appropriate for these patients.