Radial scar/complex sclerosing lesions: a clinicopathologic correlation study from a single institution

Radial scars (RSs) or complex sclerosing lesions (CSLs) of the breast are benign radiologic and histologic entities. With the introduction of population-based screening programs, their incidence has increased to 0.03% to 0.09% of all core needle biopsies (CNBs). They can pose diagnostic difficulty because their radiologic and histologic appearances mimic carcinoma. We retrospectively searched for and reviewed all cases of RS/CSL diagnosed on image-guided CNB from January 1, 1994, to August 31, 2013, at a single institution. We also assessed the pathologic reports from excisional biopsies to identify cases upstaged to atypia or neoplasm. After exclusions, 100 CNBs were identified from 97 women, which showed RS/CSL without concomitant atypia. Mean age of the women was 52.9 years. Thirty-five women (38/100 CNBs, 38%) had follow-up excision. The median size of the excised RS/CSLs was 1.2 cm; 69% were larger than 1.0 cm. Almost all excised cases (92%) showed radiologic and pathologic concordance, and 79% were designated as suspicious for malignancy (Breast Imaging Reporting and Data System level 4). The most common findings of 38 follow-up excisional biopsies were residual RS (22 [58%]), atypical lobular hyperplasia (5 [13%]), and no residual lesion (5 [13%]). Eleven excisional biopsies (29%) were upstaged to invasive or in situ carcinoma or to atypical hyperplasia. Follow-up excisional biopsy is warranted for RS/CSLs, specifically those larger than 1.0 cm with worrisome radiographic findings or with radiologic and pathologic discordance. Approximately 29% of cases were upstaged to in situ or invasive carcinomas or other high-risk lesions in our study.