Myoepithelial carcinoma of the skin: a case report.

Abstract

Cutaneous myoepithelial carcinoma (MEC) is extremely rare and its diagnosis is challenging due to its broad morphological spectrum. We reported the case of a 50-year-old woman with a 7 mm cutaneous nodule on the left nasal wing, initially misdiagnosed as a fibrous papule. The lesion recurred 6 months after excision. Histopathological analysis revealed a dermal neoplasm with epithelioid cells exhibiting moderate atypia and mitotic activity. Immunohistochemical analysis confirmed a myoepithelial phenotype with positive staining for CK7 and S-100, while excluding adnexal, vascular, muscular, histiocytic, plasmacytic, and melanocytic origins. A diagnosis of primary cutaneous MEC was established. The patient underwent complete surgical excision with clear margins, and no recurrence or metastasis was observed after 6 years of follow-up. This case highlights the diagnostic challenges associated with primary cutaneous MEC and underscores the importance of complete surgical excision. Increased awareness and further case reporting are necessary to refine diagnostic and therapeutic approaches for this rare malignancy.