A Case of Endocrine Mucin-Producing Sweat Gland Carcinoma of the Eyelid

Purpose: We report an endocrine mucin-producing sweat gland carcinoma diagnosed by biopsy in a patient who presented with an eyelid mass.Case summary: A 64-year-old male presented with a 3 x 3 mm solitary, painless pinkish mass on the right lower eyelid that had developed over the past year. The mass was excised and a biopsy was performed. The pathological findings included basaloid nodules composed of cells with eosinophilic cytoplasm, focal mucin production, and occasional glandular structures. Immunohistochemical examination was positive for cytokeratin 7 (CK-7), tumor protein 63 (P63), and the androgen receptor (AR). The patient was thus diagnosed with an endocrine mucin-producing sweat gland carcinoma. The lesion healed, and there has been no sign of recurrence over 6 months of follow-up.Conclusions: An endocrine mucin-producing sweat gland carcinoma is a very rare low-grade glandular malignancy that has not been reported in Korea previously. The prognosis is good (i.e., there is no recurrence) when the lesion is completely surgically excised. We thought it would be useful to report this very rare case.