Primitive neuroectodermal tumor of the endometrium: report of two cases, one with electron microscopic observations.

Two primary primitive neuroectodermal uterine malignant tumors are reported. One initially had the appearance of neuroblastoma but after radiotherapy showed both glial and ganglionic differentiation. The second neoplasm exhibited medulloepithelial canals, as well as glial, neuroblastic, and focal neuronal differentiation. Both patients died with widespread metastatic disease after both radiotherapy and chemotherapy.