A Case of a Malignant Cutaneous Mixed Tumor (Chondroid Syringoma) of the Scapula Treated With Staged Margin-Controlled Excision

We report a case of a malignant cutaneous mixed tumor in an 86-year-old white man who presented with a pink indurated plaque on his left scapula. He had a history of nonmelanoma skin cancers, a stage IB malignant melanoma of a lower extremity and Gleason 4 + 3 prostate cancer treated with brachytherapy, external beam irradiation, and bicalutamide. A shave biopsy was performed and histologic examination revealed infiltrative single-unit atypical cells and small ducts in a superficially transected sclerotic dermis suggestive of a poorly differentiated adenocarcinoma. No epidermal connection was identified. Immunohistochemical studies revealed that the tumor was positive for CK7, CAM5.2, and mCEA and negative for CK20, epithelial membrane antigen, P63, prostate-specific antigen, prostatic specific acid phosphatase, and alpha-methylacyl-coenzyme A racemase. A metastasis of the breast or upper digestive tract was favored, although a primary eccrine carcinoma was also considered. Imaging was performed and no other masses were identified. A slow Mohs excision was performed with negative margins. Microscopic examination revealed a biphasic neoplasm comprised of infiltrative epithelial strands and tubules consistent with an eccrine carcinoma in a hyalinized and chondromyxoid stroma within the dermis, arising from a well-circumscribed chondroid syringoma located in the deep dermis and subcutis. Areas of clear cell change, intracytoplasmic vacuolization, and mucin pools were noted. Mult...
Source: The American Journal of Dermatopathology - Category: Pathology Tags: Extraordinary Case Report Source Type: research