Synchronous invasive ductal carcinoma in encapsulated papillary ductal carcinoma

Encapsulated papillary ductal carcinoma (EPC) of the breast is a rare form of cancer with defining histopathology of encapsulation. These lesions are typically indolent but may rarely have concomitant, synchronous invasive lesions. This report details a 56-year-old black female who presented with a palpable left breast mass. Adenosis with focal fibrous and ductal hyperplasia characteristics were found on core needle biopsy. Excisional biopsy showed EPC with invasive components. A simple mastectomy was performed and a second lesion was identified as invasive ductal carcinoma. EPC typically has good prognosis and a low incidence of invasion. The risk increases in the presence of a second, synchronous lesion as in our case. Management is typically performed with breast conserving methods; however, missing a second lesion is possible. This report provides an overview of the literature and discussion of the role of MRI in preoperative workup.