malignant smooth muscle cancer that can arise almost anywhere in the body, but is most common in the uterus, abdomen, or pelvis

Leiomyosarcoma, also referred to as LMS, is a malignant (cancerous) smooth muscle tumor. It is a benign tumor originating from the same tissue called leiomyoma. It has been believed that leiomyosarcomas do not arise from leiomyomas.[1]

About 1 in 100,000 people gets diagnosed with LMS each year.[2] Leiomyosarcoma is one of the more common types of soft-tissue sarcoma, representing 10 percent to 20 percent of new cases. Leiomyosarcomas can be very unpredictable. They can remain dormant for long periods of time and recur after years. The cancer is aggressive and hardly responds to chemotherapy treatments.[3]


  1. Kumar, Vinay; Abbas, Abul; Aster, Jon (2015). Robbins and Cotran Pathologic Basis of Disease. Philadelphia, PA: Elsevier. pp. 1020–1021. ISBN 978-1-4557-2613-4.
  2. "Surveillance, Epidemiology, and End Results (SEER) Program Stat Database: Incidence—SEER 18 Regs Research Data + Hurricane Katrina Impacted Louisiana Cases, Nov 2016 Sub 2000-2014 Katrina/Rita Population Adjustment—Linked To County Attributes - Total U.S., 1969–2015 Counties, DCCPS, Surveillance Research Program". National Cancer Institute. April 2017. Retrieved June 6, 2017.
  3. "Basic info". Leiomyosarcoma.info. Archived from the original on 2009-04-30.