title: Cutaneous adnexal carcinoma with apocrine differentiation.
abstract: Primary cutaneous apocrine carcinomas are uncommon malignant neoplasms that can be difficult, if not impossible, to distinguish histologically from metastatic breast carcinomas. We present the case of a 71-year-old man with a 5-year history of extensive ulcerated plaques on the posterior neck and posterior scalp. Biopsy revealed a poorly differentiated infiltrating adenocarcinoma consistent with either primary cutaneous apocrine carcinoma or occult metastatic breast carcinoma. Immunohistochemical analysis demonstrated positive staining for cytokeratin (CK) 7, estrogen receptor, and progesterone receptor, and negative staining for p63, podoplanin, CK20, and thyroid transcription factor 1. Extensive radiologic imaging studies showed no evidence of occult breast or other internal malignancies. Based on the indolent clinical course, lack of evidence for an internal primary site, and immunohistochemical staining, the lesion was determined to be consistent with a cutaneous neoplasm with features of apocrine differentiation. This case highlights the distinction between apocrine carcinoma and other primary adnexal carcinomas for which p63 and D2-40 have been reported to be sensitive and specific markers but are negative in apocrine carcinomas.
authors.affiliation: Department of Dermatology, The George Washington University School of Medicine, Washington, DC, USA.
authors.forename: Vikram
authors.initials: V
authors.lastname: Prasad
authors.affiliation: Department of Dermatology, The George Washington University School of Medicine, Washington, DC, USA.
authors.forename: Wynn H
authors.initials: WH
authors.lastname: Kao
authors.affiliation: Department of Dermatology, University of Maryland School of Medicine, Baltimore, USA.
authors.forename: Grace F
authors.initials: GF
authors.lastname: Kao
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis* / Q000473:pathology; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D018567:Breast Neoplasms, Male / Q000175:diagnosis / Q000473:pathology; D018280:Carcinoma, Skin Appendage / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D012680:Sensitivity and Specificity; D012878:Skin Neoplasms / Q000175:diagnosis* / Q000473:pathology; D013544:Sweat Gland Neoplasms / Q000175:diagnosis* / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor