Massive cystic degeneration of a uterine leiomyoma presenting as an ovarian cyst: a case report.

An unusual case of massive cystic degeneration in an uterine leiomyoma measuring 21 cm in diameter, in a 40 year old female is being presented. It was diagnosed as a cystic adnexal tumor on ultrasonogram. Interlacing bundles of smooth muscle were identified in the cyst wall, which was confirmed on special stains. The differential diagnoses considered in this case are discussed. To the best of our knowledge, this is the largest cystic degeneration in an uterine leiomyoma reported in the literature.