Track
Case ReportsAbstract
Endocrine mucin-producing sweat gland carcinoma (EMPSGC) is an exceptionally rare, low-grade malignant adnexal neoplasm with neuroendocrine differentiation. It often arises in the periorbital region of older females and is considered a precursor to primary mucinous carcinoma.
We present a 77-year-old male veteran referred by ophthalmology for biopsy of a recurrent small, pearly papule on the left upper eyelid. The patient first presented to ophthalmology four years prior and excisional biopsy exhibited adnexal tumor with eccrine differentiation, with findings consistent with hidradenoma. Complete excision to better characterize the tumor was recommended, but patient elected for clinical monitoring given its presumed benign nature. The patient recently re-presented to ophthalmology due to tumor progression. A curette biopsy was performed with histology consistent with previous biopsy. Due to fragmented excision and poor margin evaluation, complete removal was recommended for definitive diagnosis. Patient was referred to dermatology for eyelid margin biopsy via shave, exhibiting features of EMPSGC with extravasated mucin suggesting early invasion. Immunohistochemical staining included positive PR and WT1, partially positive synaptophysin, INSM-1, GCDFP and ER, and negative chromogranin and CD56, indicative of EMPSCG. Tumor was present at biopsy edge and Mohs surgery with oculoplastic closure was planned to ensure complete removal.
Our case emphasizes diagnostic challenges posed by inadequate sampling and curette biopsies of clinically concerning lesions of the eyelid margin, a high-risk site for malignant neoplasms, such as sebaceous carcinoma and the rarer EMPSGC. While incomplete excisional and curette biopsies are minimally invasive, they can increase the risk of inaccurate histologic diagnoses.