Malignant mesenchymoma arising from a uterine leiomyoma in the menopause

Background Malignant mesenchymoma is a rare tumor and location in the uterus is even rarer. We describe the first case of malignant mesenchymoma arising from a uterine fibroid in the menopause. Case report A 64-year-old woman presented with abdominal pain and underwent surgery for a large "uterine fibroid" with suspicious features on ultrasound scan. The mass had developed after the menopause. Histology showed benign leiomyomatous tissue with malignant areas consistent with malignant mesenchymoma. Conclusion We report the first case of malignant mesenchymoma arising from the uterus in menopause. Certain radiological features may be associated with this tumor. Due to its rarity, information on management of uterine malignant mesenchymoma is lacking and management options of uterine leiomyosarcomas are reviewed as a surrogate.