Background: Cotyledonoid dissecting leiomyoma (Sternberg tumor) is a rare variant of the uterine smooth muscle tumor. Although this tumor is a benign tumor clinically and pathologically, the appearance and growth pattern is unusual, so it may be misdiagnosed as malignancy.
Case reports: We report two cases of cotyledonoid dissecting leiomyoma of the uterus that occurred in two 44- and 31-year-old women, respectively. Total hysterectomy and bilateral salpingo-oophorectomy were performed in one of the patients, and myomectomy was done in the other one. Macroscopically, both tumors were grape-like exophytic masses resembling placental tissue. The patients were well after surgery, and one patient gave birth. To our knowledge, this is the first case report of a successful delivery after myomectomy of this tumor.
Conclusion: To prevent aggressive surgery it is important to recognize that this tumor is a benign and unusual appearing variant of leiomyoma. A fertility-sparing surgical procedure should be considered if the patient wishes to preserve her fertility.