Unilateral primary ovarian leiomyoma masqueraded as ovarian fibroma: A histopathological diagnosis

Leiomyoma is the commonest benign mesenchymal tumor of the uterus, which can be developed at any site where smooth muscle cells are found. The broad ligament is the most common and ovary is one of the rarest extrauterine sites, accounting for 0.5-1% of all benign ovarian tumors. Herein, we report a case of ovarian leiomyoma in a perimenopausal female, clinically presented with heavy menstrual bleed, radiologically diagnosed as subserosal uterine fibroid. Intraoperatively, it was considered as ovarian fibroma but finally diagnosed as ovarian leiomyoma on histomorphology, which was confirmed on special stains and immunohistochemistry. A review of literature showed that less than 100 cases of primary ovarian leiomyomata have been reported until now. Ovarian leiomyoma is usually small, asymptomatic, and an incidental finding mostly, usually synchronously seen with uterine leiomyoma. Ovarian leiomyoma is a rare tumor, often misdiagnosed prior to surgical removal and it should be differentiated from other spindle cell neoplasm and solid tumors of the ovary.