Breast lesions associated with mammographic architectural distortion: a study of 588 core needle biopsies

Architectural distortion (AD) on mammography is a localized alteration in the uniform texture of the breast characterized by lines radiating from a central point. Radiologic/pathologic correlation is challenging because the types of lesions associated with AD are not well defined and, thus, what signifies a discordant finding requiring excision is less clear. This retrospective case series was performed to elucidate the pathologic lesions associated with AD. Over a 6-year period, 588 core needle biopsies (CNBs) were performed for AD. Thirty-eight percent of the lesions were AD alone (single feature AD) and 62% had additional imaging features (multi-feature AD). Overall, 31% showed invasive carcinoma or ductal carcinoma in situ (DCIS), 37% showed benign lesions likely to correlate with AD, and 32% showed nonspecific benign findings. The invasive carcinomas tended to be low-grade (60%), ER-positive (98%), HER2-negative (98%), and often had lobular features (52%). Ninety-two percent were AJCC pathologic stage group I. Ninety-four cases of benign findings that correlated with AD without atypia underwent excision, and only one was found to have DCIS adjacent to the sclerosing lesion (1%). The remaining cases had benign findings without a clear correlate for AD. Sixty-eight cases without atypia underwent excision, and six multi-feature AD were upgraded to invasive carcinoma (9%). In conclusion, about one-third of CNBs for lesions associated with AD reveal carcinomas that are predominantly invasive, low-grade, ER-positive, HER2-negative, and low stage. Single-feature AD differed from multi-feature AD due to a lower number of carcinomas on CNB (18% vs 39%). For CNBs showing benign lesions on biopsy with a correlate for AD, the finding of malignancy on excision is low (1%). Radiologic/pathologic correlation and decisions to recommend excision will continue to be a challenge after CNB reveals nonspecific findings as some patients with multi-feature AD were found to have undetected invasive carcinomas.