Primary neuroectodermal tumors of the ovary. A report of 25 cases.

Twenty-five primary ovarian neuroectodermal tumors occurred in females from 6 to 69 (average, 23) years of age; they had the usual presenting symptoms of abdominal swelling or pain. The tumors, which varied from cystic to solid, ranged from 4 to 20 cm (average, 14 cm) in diameter. Microscopic examination revealed three histologic categories--differentiated, primitive, and anaplastic--with the tumors in the first group having a better prognosis than those in the other two groups. Five of the six differentiated gliomas were pure ependymomas, and one was an ependymoma with an astrocytoma component; none contained teratomatous elements. Two patients with stage I tumors were alive 4 and 5 years postoperatively. The one patient with stage IIA tumor was free of disease at 3 years; one of the two patients with a stage III tumor died of tumor after 5 years, and one had two recurrences but was alive and well at 5 years. Twelve tumors were primitive, resembling medulloepithelioma, ependymoblastoma, neuroblastoma or medulloblastoma. Seven tumors had teratomatous foci of other types, including three dermoid cysts. Three patients with stage I tumors were alive at 7 months, 3 years, and 9 years postoperatively; six of seven patients with stage III tumors died of tumor 2 to 20 months postoperatively, and one was alive with disease at 1 year. Seven tumors were anaplastic, resembling glioblastoma. All contained foci of squamous epithelium. One patient with stage IA tumor died of tumor at 2 years, but two were free of tumor after 3 and 4 years. One patient with a stage IIA tumor died of disease after 5 years; another was alive with tumor at 1 year. One patient with a stage III tumor died after 4 months. The differential diagnosis of neuroectodermal tumors of the ovary includes many primary and metastatic ovarian neoplasms of diverse types, and distinction among them is important. Neuroectodermal tumors should be considered when examining unusual ovarian tumors, particularly if the patient is young.