Microcystic Adnexal Carcinoma. A Rare Entity

Area of Science:

• Dermatopathology
• Surgical Oncology

Background:

• Microcystic adnexal carcinoma (MAC) is a rare, locally aggressive malignant tumor originating from sweat glands.
• It typically affects the deep dermis, sparing the epidermis, and has a low rate of lymphatic or metastatic spread.

Observation:

• A case report details a 46-year-old woman with a slow-growing upper lip lesion diagnosed as MAC.
• The lesion exhibited characteristics of an adnexal epithelial neoplasm with imprecise borders, perineural invasion, and dermal and adipose tissue infiltration.

Findings:

• MAC presents as a solitary papule or plaque on the central face, common in middle-aged Caucasian females.
• Histopathology reveals nests and strands of cells in the deep dermis with perineural invasion, necessitating incisional biopsy for diagnosis.

Implications:

• Due to its rarity, there is no established consensus on the optimal management or follow-up for MAC.
• MAC should be considered in the differential diagnosis of facial lesions, particularly those with aggressive local characteristics.