Perineural and Vascular Invasion in an Endocrine Mucin-Producing Sweat Gland Carcinoma of the Ear with Associated Mucinous Carcinoma

Endocrine mucin-producing sweat gland carcinoma (EMPSGC) is a low-grade, indolent tumor found almost exclusively on the eyelids that may histologically mimic metastatic breast carcinoma. To our knowledge, we present the first case of EMPSGC located on the external ear, and the first case with histologic evidence of vascular and perineural invasion. Due to the aggressive potential of this lesion, wide local excision and adjuvant radiation therapy were performed to help reduce the risk of recurrence.