Cellular fibroma of the ovary containing Leydig cell hyperplasia: a case report.

Ovarian stromal tumors containing Leydig cell components are rare. Only a few cases of ovarian stromal Leydig cell tumors characterized by clusters of Leydig cells have been reported to date. Here, we present the first case report of a 65-year-old woman with a cellular fibroma of the ovary containing Leydig cell hyperplasia. Microscopic examination revealed the proliferation of spindle cells arranged in intersecting bundles with mild nuclear atypia and an average of 2-3 mitotic figures per ten high-power fields. Multifocal nests of polygonal cells with abundant eosinophilic cytoplasm and round nuclei were seen within the spindle cells. Final pathology of the tumor revealed a cellular fibroma including Leydig cell hyperplasia.