Endodermal sinus tumor of the ovary. Clinicopathologic study of 6 cases

6 cases of endodermal sinus tumor of the ovary are presented. In 4 patients pure endodermal sinus tumor was found microscopically. 1 patient had endodermal sinus tumor in one ovary and gonadoblastoma in the contralateral one. In another case endodermal sinus tumor was accompanied by an embryonal teratoma. Histologically, the tumor had characteristic features with meshwork of spaces and channels lined by embryonal cells, glomerulus-like structures known as Schiller-Duval bodies, solid aggregates of epithelial cells, hyaline basement membranes and round, PAS-positive small globules found both intra- and extracellulary. In 1 patient the elevated serum alpha-fetoprotein was stated. All patients were treated surgically with adjunctive radiation and/or with chemical agents. None of them were cured. The median duration of survival amounted to 8.5 months. Discussing the value of the more recent approach to diagnostic and therapeutic methods found in the literature, it must be emphasized that the demonstration of elevated serum alpha-fetoprotein in patient with that tumor lend not only further support to its yolk sac origin but also might be useful to monitor response to the therapy applied. It is also of prognostic significance by indicating the presence of residual or recurrent disease, even in its subclinical stage. Combined postoperative irradiation and triple chemotherapy according to the VAC regimen of patients can prevent recurrence and in some cases even may cause permanent remission of the neoplasm.