Cancerous (malignant) tumors of the connective tissues are called “sarcomas”. The term sarcoma comes from a Greek word meaning fleshy growth. Sarcoma arises in the connective tissue of the body. Normal connective tissue include, fat, blood vessels, nerves, bones, muscles, deep skin tissues, and cartilage. Sarcomas are divided into two main groups, bone sarcomas and soft tissue sarcomas. They are further subclassified based on the type of presumed cell of origin found in the tumor. They all share certain microscopic characteristics and have similar symptoms. Sarcomas can develop in children and adults. For children under 20 approximately 15 percent of cancer diagnosis are sarcomas. Although rare, there are approximately 14,000 new cases of sarcoma diagnosed each year in the United States. In general sarcomas are divided into the large groups of soft tissue sarcoma and bone sarcomas.