Axillary apocrine carcinoma associated with apocrine adenoma and apocrine gland hyperplasia.

Apocrine carcinomas represent a rare group of tumors with a potential for destructive local invasion, regional and distant metastases, and are equally common in both sexes. A case of a 79-year-old woman with axillary apocrine carcinoma associated with apocrine adenoma and apocrine gland hyperplasia is presented. To our knowledge, this is the first case diagnosed in a Caucasian and also the first case diagnosed in a female patient. Grossly, the tumor measured 3.2x1.5x1.2 cm and on cut section appeared granular, white to gray-tanned. Microscopically, the tumor was located in the dermis, poorly demarcated, focally necrotic with ulcerated overlying skin. It was predominantly composed of complex, closely packed tubuloglandular structures but in few areas papillary structures were also observed. The cells contained abundant eosinophilic, finely granular cytoplasm with pleomorphic nuclei and showed apocrine-like decapitation. The cytoplasm contained periodic acid Schiff diastase resistant granules. Mitoses were frequent and some were atypical. In one area, the tumor was lobular and composed of tubular structures lined with one layer of uniform cuboidal or columnar eosinophilic cells, indicating a pre-existing apocrine adenoma. Beneath the tumor, in the deep dermis and subcutaneous tissue, hyperplastic apocrine glands were also found. No additional therapy was used, and one year after the surgery the patient was alive and showed no signs of tumor spread. This and previously reported cases suggest that apocrine hyperplasia and apocrine adenoma may represent successive steps in the development of apocrine carcinoma.