A case of cotyledonoid leiomyoma and review of the literature.

We report a case of a rare, unusual benign tumor, the cotyledonoid leiomyoma or Sternberg tumor, detected incidentally in a 67-year-old woman who underwent total hysterectomy and bilateral salpingo-oophorectomy because of a persisting left ovarian cyst of 5 cm. This is the 14th case of cotyledonoid leiomyoma and 2nd case which had no intrauterine portion but had extrauterine extensions. At laparotomy, it was detected that a deep red nodular papillary tumor had been dissecting the posterior leaf of the left broad ligament, projecting into the abdominal cavity just near the left cornu of the uterus, and extending in downward direction. The remaining portion was lying between the layers of the left broad ligament and arose from the subserosa of the left side of the uterine isthmus. Although the bizarre and unusual shape was in favor of malignity, the frozen-section examination revealed a benign histology. Although the cotyledonoid leiomyoma is a benign entity, it may suggest a malignant disease owing to its unusual sarcomatoid appearance and its rarity. Therefore, awareness of obstetricians and gynecologists regarding this rare entity will prevent unnecessary anxiety and interventions.