Flat epithelial atypia of the breast: characteristics and behaviors

BackgroundFlat epithelial atypia (FEA) increasingly is being recognized as a pathologic entity on core needle biopsies. However, definitive management of this columnar cell lesion remains debatable because its malignant potential is unknown.MethodsA PubMed search for “flat epithelial atypia” and “columnar cell lesions” was performed.ResultsFEA commonly was encountered in the background of higher-grade lesions such as atypical ductal hyperplasia, ductal carcinoma in situ, and tubular and lobular carcinomas. Its molecular and cytogenetic profile revealed some alterations similar to precancerous lesions. Pure FEA on core needle biopsies was upgraded to higher-grade lesions on subsequent surgical excision.ConclusionsCurrent management of FEA is best achieved through a multidisciplinary review considering various factors to determine if surgical excision is warranted. Further studies are required to elucidate the malignant potential of this columnar cell lesion.