15713 Endocrine mucin-producing sweat gland carcinoma: Expanding the differential of eyelid tumors

Abstract

Endocrine mucin-producing sweat gland carcinoma (EMPSGC) is an uncommon low-grade adnexal neoplasm that most commonly occurs on the eyelid of elderly women. Clinically, this neoplasm presents as a flesh-colored to bluish or pink papule, nodule or swelling, often with overlying telangiectasias. It is often mistaken for basal cell carcinoma. Histopathologically, EMPSGC is positive for one or more neuroendocrine markers: synaptophysin, chromogranin, or neuron-specific enolase. It is often also positive for cytokeratin 7 (CK7), estrogen receptor (ER), and progesterone receptor (PR). Although EMPSGC is uncommon, it is being increasingly reported in the literature. This is likely due to an increase in diagnosis, not necessarily an increase in incidence. EMPSGC can be locally aggressive and can recur, but it is not known to metastasize. Treatment options include excision with wide margins or Mohs micrographic surgery. We present a case series of three biopsy proven EMPSGCs at our institution that demonstrated classic histopathologic and immunohistochemical patterns. We hope to increase awareness of this entity in the clinical and histopathologic differential diagnosis of eyelid tumors. We also hope to stress the importance of using immunohistochemistry to aid in the diagnosis of basaloid neoplasms.