Malignant peripheral primitive neuroectodermal tumor of the uterus.

Peripheral primitive neuroectodermal tumor (PPNET) is rare, occurring most often in young adults. Approximately 50 cases have been reported, with only four cases involving the female genital tract. We report the fifth patient. The term "PPNET" should be used only for tumors with neuroectodermal elements exclusively that occur at sites outside the central and sympathetic nervous system. The pathologic differential diagnoses include rhabdomyosarcoma, immature malignant teratoma, small cell carcinoma of the cervix, and ganglioneuroma. Therapy for this tumor has varied, and no effective regimen has been established.