Primitive neuroectodermal tumor of the testis. Report of a case.

A 30-year-old man died of a testicular tumor with widespread metastases. Both the right testis and the adjoining epididymis were replaced by a mass that consisted mainly of small cells, but differentiated focally into medullary tubules, ependymal rosettes, and glia in which glial fibrillary acidic protein was demonstrated; rare foci of cartilage and cellular mesenchyme established the teratomatous nature of the neoplasm. We believe this is the first reported case of a primitive neuroectodermal tumor of the testis.