Oxyphilic clear cell carcinoma of the ovary. A report of nine cases.

Nine clear cell carcinomas (CCC) of the ovary with a prominent component of cells with abundant eosinophilic cytoplasm are reported. The majority of these tumors--which we have designated "oxyphilic clear cell carcinomas"--were misinterpreted by the referring pathologists as tumors of other types. Each specimen, however, had one or more features establishing it as a clear cell carcinoma, including tubules and cysts lined by cuboidal, hobnail, or flattened cells; nests and sheets of cells with abundant clear cytoplasm containing glycogen; and an adjacent adenofibromatous component. Two tumors were bilateral. The ages of the patients (average, 55 years), their clinical presentation, and the gross appearance of the neoplasms were similar to those of clear cell carcinomas in general. The diagnosis of clear cell carcinoma should always be considered in the differential diagnosis of an ovarian tumor with oxyphil cells, particularly if the patient is postmenopausal. Thorough sampling should be undertaken in such cases to identify other, more typical foci of clear cell carcinoma in order to avoid misdiagnosis.