Leiomyosarcoma

Leiomyosarcoma (Gr. "smooth muscle connective tissue tumor"), also referred to as LMS, is a malignant (cancerous) smooth muscle tumor. It must not be confused with leiomyoma, which is a benign tumor originating from the same tissue. It is also important to note that leiomyosarcomas do not arise from leiomyomas.

Leiomyosarcoma is a relatively rare form of cancer, and accounts for 5–10% of soft tissue sarcomas, which are in themselves relatively rare. Leiomyosarcomas can be very unpredictable. They can remain dormant for long periods of time and recur after years. It is a resistant cancer, meaning generally not very responsive to chemotherapy or radiation. The best outcomes occur when it can be removed surgically with wide margins early, while small and still in situ.

Location

Smooth muscle cells make up the involuntary muscles, which are found in most parts of the body, including the uterus, stomach and intestines, the walls of all blood vessels, and the skin. It is therefore possible for leiomyosarcomas to appear at any site in the body. They are most commonly found in the uterus,stomach, small intestine and retroperitoneum.