Oncocytic carcinoma of the male breast.

Primary oncocytic carcinoma of the breast was diagnosed in a 76-year-old man. The histologic and electron microscopic features are characteristic of oncocytic neoplasms that occur at other sites, such as salivary glands and endocrine organs. The pathologic features and the presence of estrogen receptors biochemically are distinct from apocrine carcinoma. The patient is alive 7 years after modified radical mastectomy without additional chemotherapy or radiotherapy.