Endodermal sinus tumor: the Stanford experience and the first reported case arising in the vulva.

A review of the histology, clinical findings and results of therapy in 9 females with endodermal sinus tumor (EST) is presented. Five patients had histologically pure EST; 4 had EST mixed with other germ cell components. The site of primary tumor was the ovary in 8 of the 9 females; the remaining patient with an extraovarian primary represents the first reported case of EST arising in the vulva. The addition of combination chemotherapy has prolonged survival over historical controls treated with surgery or surgery plus irradiation. Adjuvant chemotherapy appears warranted as treatment for occult metastatic disease; postoperative radiation therapy appears useful in providing local control of primary disease. There is a suggestion of increased sensitivity of EST to combination chemotherapy as compared to other germ cell histologies with which it is commonly admixed.