Endodermal sinus tumor and mucinous cystadenofibroma of the ovary. Occurrence in an 82-year-old woman.

We encountered an unusual ovarian tumor consisting of a mixture of typical endodermal sinus tumor (EST) and mucinous cystadenofibroma that occurred in the ovary of an 82-year-old female patient. The EST component showed the classic histologic features of this tumor. Serum alpha-fetoprotein (AFP) level was not determined. Tumor stains were negative for AFP but positive for alpha-1-antitrypsin. The malignant germ cell component was intimately associated with the benign mucinous component. Focal production of epithelial mucin and carcinoembryonic antigen (CEA) in the EST component suggested a probable association between the two tumor types. The tumor was confined to one ovary, and the patient is disease-free 2 years after surgical therapy. This neoplasm is unique not only for the malignant germ cell component occurring in an 82-year-old woman, but for the unusual combination of tumor types. The pathogenesis is unknown.