Extraovarian pelvic yolk sac tumors.

The clinical and pathologic features of four extraovarian pelvic yolk sac tumors (YST) are described. The women, 17 to 39 years of age, were found to have a pelvic mass on physical examination, or in one case, at cesarean section. The tumors were bulky and arose within, or in close proximity to, the uterus. One tumor involved the endometrial cavity and myometrium extensively, another was attached to the anterior uterine serosa, another was in the cul-de-sac, and one lay between the lower uterine segment and urinary bladder. The ovaries were grossly unremarkable in all cases. Peritoneal metastases were present at the time of operation in two patients and were documented on histologic examination in a third. The serum alpha fetoprotein (AFP) level was elevated postoperatively in the three patients in whom it was determined. Three of the YST were pure and had a typical histologic appearance, whereas the fourth had an endometrioid-like glandular pattern and was associated with a teratoma. Immunohistochemical stains performed in three cases all showed AFP and alpha-1-antitrypsin (AAT). All patients received postoperative combination chemotherapy. Two of them died of tumor 14 and 24 months, respectively, postoperatively and two were disease-free 6 and 8.5 years, respectively, postoperatively.