Leiomyoma (fibroid) Introduction benign smooth muscle tumor arising from myometrium malignant transformation is rare most common of all tumors in females multiple tumors with well-demarcated borders more common in blacks estrogen sensitive tumor size ↑ with pregnancy and ↓ with menopause peak occurrence at 20-40 years of age (premenopausal) Presentation symptoms may be asymptomatic abnormal uterine bleeding recurrent miscarriage physical exam anemia result of bleeding pelvic mass on abdominal palpation Evaluation histology whorled pattern of smooth muscle cells Prognosis, Prevention, and Complications does not progress to leiomyosarcoma leiomyoma Leiomyosarcoma Introduction malignant smooth muscle tumor arising from myometrium bulky, irregularly shaped tumor with areas of necrosis and hemorrhage typically arising de novo (not a progression of a benign leiomyoma) more common in blacks most commonly seen in postmenopausal women Presentation symptoms abnormal uterine bleeding physical exam may protrude from cervix Prognosis, Prevention, and Complications highly aggressive tumor with tendency to recur leiomyosarcoma