Leiomyosarcoma

Leiomyosarcoma (LMS) is a malignant (cancerous) tumor that arises from smooth muscle cells, which are found in the walls of blood vessels, the uterus, the gastrointestinal tract, the skin, and other soft tissue locations throughout the body. It is classified as a soft tissue sarcoma and represents one of the more common subtypes of this rare group of cancers. Leiomyosarcoma can occur in virtually any anatomical site but is most frequently found in the uterus (uterine leiomyosarcoma), the retroperitoneum (the area behind the abdominal cavity), and the extremities. It can also arise from large blood vessels, particularly the inferior vena cava. The tumor tends to be aggressive, with a propensity for local recurrence and distant metastasis, most commonly to the lungs and liver. Key symptoms depend on the location of the tumor. Patients may present with a painless or painful mass, abdominal pain or swelling, abnormal uterine bleeding (in uterine LMS), gastrointestinal symptoms, or symptoms related to compression of nearby structures. Constitutional symptoms such as fatigue and unintentional weight loss may occur, particularly in advanced disease. Because the tumor can grow silently in deep body compartments, diagnosis is sometimes delayed. The current treatment landscape centers on surgical resection with wide margins as the primary curative approach. For localized disease, complete surgical removal offers the best chance of long-term survival. Radiation therapy may be used as an adjunct, particularly for extremity or retroperitoneal tumors, to improve local control. Chemotherapy, typically with doxorubicin-based regimens, trabectedin, or gemcitabine plus docetaxel, is used for advanced or metastatic disease, though responses are often limited. Newer targeted therapies and immunotherapy approaches are under investigation in clinical trials. Prognosis varies significantly based on tumor size, grade, location, and stage at diagnosis, with five-year survival rates ranging widely depending on these factors.

Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.

Common questions about Leiomyosarcoma