Leiomyosarcoma of the Inferior Vena Cava
The vascular system has the lowest incidence of malignant tumors in the human body. Leiomyosarcoma (LMS) is the most common malignancy arising from the vascular system. It is a rare soft tissue tumor arising from smooth muscle cells in the middle layer of the vessel wall, which grows slowly and rarely invades adjacent organs. It comprises approximately 2% of all human leiomyosarcomas and 0.5% of all soft tissue tumors. The inferior vena cava (IVC) is the area of the entire vascular system where tumor is most likely to occur. More than half of all vascular leiomyosarcomas arises from the IVC, while some extremely rare tumors originate in the superior vena cava, femoral vein, and popliteal vein.