Pilomatrixoma, a Rare Mimicker of Male Breast Cancer

Pilomatrixoma or calcifying epithelioma of Malherbe is a benign skin tumor arising from the hair follicle; breast occurrence is considered a rarity. Clinically presenting as a palpable abnormality and with both benign and malignant mammographic and sonographic features, it can be easily misdiagnosed as a breast neoplasm. We report a very rare case of pilomatrixoma of the male breast in a 36-year-old male presenting with a firm, superficial nodule in the upper outer quadrant. Though the sonographic trifecta of imaging features (shape- margins-orientation/oval, circumscribed mass, parallel to the skin) is consistent with a benign lesion, a histologic diagnosis was warranted based on its most suspicious feature of internal pleomorphic calcifications. Pathologic diagnosis revealed the uncommon benign entity of pilomatrixoma in the male breast. Our patient was recommended for surgical excision based on current literature recommendations for management in most reports of pilomatrixoma. One alternative recommendation presented in a single report of pilomatrixoma in the breast supported follow-up imaging based on benign imaging characteristics.