Leiomyosarcoma is a rare type of cancer that affects smooth muscle tissue. These tumors are most common in the abdomen, but can occur anywhere in the body, including the uterus. Other common sites include blood vessels and skin.
Abdominal leiomyosarcoma tumors can measure over 4 inches (10 centimeters) across and may be accompanied by pain, weight loss, nausea or vomiting.
Leiomyosarcoma also can affect large blood vessels, particularly the vein that carries blood from the lower part of the body back to the heart (inferior vena cava) and the artery that carries blood from the heart to the lungs (pulmonary artery).
Leiomyosarcoma can be mistaken for many other types of tumors and benign growths, including uterine fibroids (leiomyomas).
In fact, most of the leiomyosarcomas that occur in the uterus are presumed to be fibroids because that's what they look like on imaging tests. The truth is revealed only after a pathologist examines the tissue after a hysterectomy.
Surgical removal is the mainstay of treatment for leiomyosarcoma, regardless of the location of the tumor in the body.
In the past, a device called a morcellator was often used to grind the uterus into smaller pieces to aid in the removal of tissue during hysterectomies performed with scopes through small incisions.
The Food and Drug Administration (FDA) now recommends that most women, especially those past menopause, avoid morcellation of the uterus or fibroids because the procedure may increase the risk of spreading cancer if a previously undiagnosed cancerous mass is morcellated.
About a third of the leiomyosarcomas that occur in the uterus have already spread to other parts of the body at the time of diagnosis.
While chemotherapy and radiation is generally not used in early-stage uterine leiomyosarcoma, they are used to treat the tumors that have spread to other parts of the body.