Types & Subtypes
Sarcomas are divided into two main categories:
- Bone tumors
- Soft-tissue sarcomas
Sarcomas are further subclassified based on the specific type of cell that makes up the cancer. This is known as the sarcoma, or histologic, subtype. There are more than 20 to 30 different types of sarcoma subtypes. The natural history and prognosis of any particular sarcoma will be determined by the histologic (or molecular) subtype, histologic grade, and tumor size.
The most common type of bone cancer is osteosarcoma. Because it occurs in growing bones, it is most often found in teenagers. Osteogenic sarcoma is one of the few cancers that begins in the bone and spreads elsewhere. Other bone sarcomas that begin in bone include Ewing's sarcoma. Sarcomas of bone are much less comman than benign bone tumors or malignant (metastasis) from other locations (breast, lung, prostate, etc.)
Subtypes of Sarcomas
The most common subtypes of sarcoma include:
- Angiosarcoma Malignant tumor that resembles blood or lymphatic vessels
- Chondrosarcoma Tumors are from cartilage cells
- Ewing's Sarcoma Class of disease that arises from very primitive cells in the body
- Fibrosarcoma Cancer of the fibroblast-type cells in the body; fibroblast-type cells form scars, and do other important connective functions
- Gastrointestinal Stromal Tumor Increasingly recognized diagnosis of connective tissue cancerous cells that support the gastrointestinal tract
- Kaposi's Sarcoma Tumor of cells found in the tissues under the skin or mucous membranes that line the mouth, nose, and anus. Kaposi's sarcoma causes red or purple patches on the skin and/or mucous membranes, and spreads to other organs in the body. Approximately 95 percent of all of cases of Kaposi's sarcoma in the United States have been diagnosed in homosexual or bisexual men.
- Liposarcoma Malignant tumor that develops from fat tissue; most often in the retroperitoneum (tissue at the back of the abdominal cavity), but can also be found in the soft tissues of the limbs.
- Leiomyosarcoma Malignant tumor that develops from smooth muscle tissue found in abdominal and pelvic organs and blood vessels. (Unlike skeletal muscle, which you can contract voluntarily, your brain doesn't have conscious control over smooth muscle.)
- Malignant Peripheral Nerve Sheath Tumor Arises out of nerves or nerve tissue outside of the brain and spine.
- Osteosarcoma Tumor of cells that form bone
- Rhabdomyosarcoma Malignant tumor that resembles developing skeletal muscle. Most commonly grows in the arms and legs, but can also develop in the head or neck area, as well as the urinary and reproductive organs. Rhabdomyosarcoma accounts for more than half of all the soft-tissue sarcomas diagnosed in children. Most children are diagnosed at less than nine years of age, but rhabdomyosarcoma can occur at any age.
- Synovial Sarcoma Malignant tumor made up of cells that resemble the cells found in joints (synovial cells line the joints). Synovial sarcoma can arise in any location in the body, and often appears in young adults.