CLINICAL: Leiomyosarcoma is the most common uterine sarcoma (>50%) and accounts for 1-2% of all uterine malignancies. It is slightly more common in black women as compared to white women and in those on tamoxifen therapy for breast cancer. Most women are older than 50 years. The presenting features include abnormal vaginal bleeding, palpable mass in the pelvis, and pelvic/abdominal pain. The clinical presentation overlaps with leiomyomas. Rare cases present with hemoperitoneum (due to tumor rupture), extrauterine extension, or distant metastases. Unlike with carcinosarcoma, there is no association with prior pelvic radiation. GROSS: Leiomyosarcoma are usually large, poorly-circumscribed, multinodular masses with a mean diameter of 10 cm. About one-fourth of cases are < 5 cm in size. The most common uterine location is intramural, followed by submucosal, subserosal, and cervical. The cut surface is soft, yellow-tan, bulging with foci of hemorrhage and necrosis. Unlike leiomyomas, there is no prominent whorled appearance. A sharp line of demarcation from normal myometrium is not present. CASE HISTORY: This hysterectomy specimen is from a 65 y/o female who presented with intermittent vaginal bleeding of 6 months' duration. Clinical examination revealed a large pelvic mass. CT abdomen/pelvis showed a 16 x 14 x 12 cm multilobular heterogenously enhancing pelvic mass. Uterus and ovaries could not be appreciated separately. Hysterectomy specimen measured 20 x 14 x 12 cm and consisted of multinodular firm to hard mass. A portion of the uterine fundus and small portion of cervix (arrow) could be identified. Fallopian tubes and ovaries appeared engulfed by the mass. The cut surface was fleshy, yellow-tan, lobulated with areas of necrosis. Microscopic examination confirmed high-grade leiomyosarcoma. Case courtesy of: Dr. Sanjay D. Deshmukh, Professor of Pathology, Dr. Vithalrao Vikhe Patil Foundation's Medical College & Hospitals, Ahmednagar, India.