Sarcoma is a type of cancer that develops in the connective tissue or tissues derived therefrom: bone, cartilage, fatty tissue, muscle, blood vessels, or other connective or supportive tissue.
Depending on the groups of cells affected by the cancer, sarcoma has a different name, such as osteosarcoma that originates in bone, chondrosarcoma that develops fromcartilage cells (bones and joints), or leiomyosarcoma which is an aggressive form of sarcoma that develops in the smooth muscles.
There are two types of sarcomas, categorized depending on the types of cells the tumor originates:
Connective Tissue (Soft Tissue) Sarcomas – These types of cancers can occur anywhere in the body, but nearly 43% of them occur in the extremities (arms, legs,…); 34% develop in or around the internal organs (uterus, heart,…); 10% originate in the trunk (chest, back, …); and13% occur in other soft tissues in the body. In very rare cases, soft tissue sarcomasdevelop in the digestive system. A small percentage of these tumors can be gastrointestinal stromal tumors(GIST), mostly in the stomach or small intestine.
Some of the most common soft tissue sarcomas include:
- Fibrosarcoma , also known as malignant fibrous histiocytoma (MFH), originates in fibroustissue
- Liposarcoma , originates in fatty tissue, one of the most common types of soft tissue sarcoma of the extremities
- Leiomyosarcoma originates in the smooth muscle tissue, which is a very aggressive type of soft tissue sarcoma.
- Rhabdomyosarcoma , commonly referred to as RMS, originates in skeletal muscle orcells which develop into skeletal muscles.
- Epithelioid hemangioendothelioma (also angiosarcoma, lymphangiosarcoma, and Kaposi’s sarcoma), arises from the lymphatic vessels (endothelial cells of liver and others).
- Glomangiosarcome and hemangiopericytoma that originate in the perivascular tissuenear or around blood vessels.
- Synovial sarcoma(also called malignant synovioma), which usually affects the cells near to the joints of the arm, neck or leg.
- Malignant Schwannomasand neurofibrosarcomas, whichoriginate in the cells of the peripheral nerves.
- Gastrointestinal stromal tumors or malignant mesenchymoma, arises from mesenchymal cells, which grow in connective tissue, blood vessels and lymphatic tissue.
Specialized tissue such as bone – this group of sarcomas include osteosarcoma, which arises from the osteoid tissue (osseous tissue before calcification) in the bone; chondrosarcomas, derived from cartilage tissue (bones and joints); Ewing’s sarcoma usually originates in bone butmay also occur in the soft tissues: muscle, fatty tissue, fibrous tissue, blood vessels or othersupporting tissues.
Sarcoma is a rare cancer that represents around 1% of all new cancer cases, affecting about15,000 new individuals in the United States every year . Although it can affect people of all ages,sarcoma is more often diagnosed in children and young adults. But certain types of sarcomas are more common to specific age groups; soft tissue sarcomas accounts for 7 percent of all cancersin children.