Immunocytochemical and ultrastructural diagnosis of a rare mixed apocrine-medullary carcinoma of the breast in a fine needle aspirate.
A rare mixed apocrine-medullary mammary carcinoma in a 57-year-old woman was preoperatively diagnosed by fine needle aspiration cytology. The aspirate was characterized by carcinoma cells with an apocrine differentiation and significant cellular atypia admixed with many lymphocytes and plasma cells. These findings were confirmed by histologic examination of the breast tumor and its metastasis in lymph nodes. Electron microscopy (EM) and immunoperoxidase staining for cytokeratin, S-100 protein, epithelial membrane antigen and carcinoembryonic antigen were done on samples of the aspirated material. Although immunostaining was of little help in this case, the EM findings did show many carcinomatous cells of apocrine type in the tumor.
Biopsy, Needle↗