Leiomyosarcoma (leiomyosarcoma; from the Greek. leios - smooth; mys, myos - muscle + sarcoma) is a malignant tumor originating in the smooth muscle fibers. More often than in other organs, the species occurs in the uterus, often in the stomach, intestine, rectum, bladder, kidneys. The tumor plotnostei or soft consistency, white or pink, with hemorrhage, necrosis centers. Histologically uterine leiomyosarcoma variable. Typical L. similar to leiomyomata, to differentiate from the past should the number of mitoses and infiltrating growth. Most HP has a strong cellular ativismo, built of large beams spindle-shaped or round cells with massive hyperchromic cores and less acidophilus than normal, protoplasm; meet ugly giant cells. Many atypical mitoses. Sometimes cellular atypism so great that it is difficult to determine the origin of the tumor of smooth muscle. Metastasize uterine leiomyosarcoma (at a late stage of the disease in the liver, kidneys, lungs, and the abdominal cavity. Surgical treatment.