Scientists do not know what causes leiomyosarcoma, but genetic conditions and environmental factors, such as exposure to levels of radiation that fight cancer, may increase risk, according to the LeioMyoSarcoma Direct Research Foundation. Exposure to particular chemical herbicides might also increase the risk of developing the rare disease. Leiomyosarcomas are malignant tumors that originate in smooth, involuntary muscle tissue, including the uterus, stomach, lungs and liver.
Leiomyosarcomas can occur almost anywhere in the body, such as on skin and in the heart, pancreas and intestines, according to WebMD. The tumors develop in the uterus most often and they typically metastasize through the bloodstream; physicians rarely find them in the lymphatic system.
Leiomyosarcoma patients can have varying prognoses, based on the tumor size, location, type and extent of metastasis, explains the LeioMyoSarcoma Direct Research Foundation. Numerous patients with stage 1 tumors have survived long-term, while survival rates are lower for patients with high-grade, rapidly growing tumors that have metastasized extensively. Treatments include surgery, chemotherapy, targeted inhibitor or disruptor drugs,, radiation and radiology. Immunotherapy treatments, such as dendritic cell vaccines, are in development, and hormonal therapy for uterine tumors may be effective. Doctors cannot recommend ways of preventing the tumors because they don't know what causes them.