About Sarcoma

What is Sarcoma?

Sarcoma is a class of rare cancers that arise from connective tissues. Normal connective tissues include fat, muscle, blood vessels, deep skin tissues, nerves, bones, and cartilage.

The term, sarcoma, comes from a Greek word meaning "fleshy growth." While sarcomas can develop in any part of the body, half of them develop in the arms or legs. The rest develop in the trunk, head and neck area, internal organs, or the retroperitoneum (the back of the abdominal cavity).

There are close to 10,000 new cases of sarcoma diagnosed in the United States each year, representing just one percent of all cancer cases. The majority of the cases (close to 8,000) are soft-tissue sarcomas; the other 2,000 or so are bone cancers. Patients with a soft-tissue sarcoma typically present with a painless, firm, soft-tissue mass, while patients with osseous sarcomas present with pain.

The typical diagnostic delay varies from three to 12 months, depending on the anatomic location of the tumor and the care received.

Adult patients over the age of 40 years who present with a bony abnormality or bone tumor should be further evaluated for an unknown primary tumor of lungs, kidneys, breast, or prostate.

Types of Sarcomas Sarcomas are divided into two main categories: bone tumors and 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 50 different types of soft-tissue sarcomas, more than half of which are malignant. The natural history or behavior of any particular sarcoma will be determined by the histologic or molecular subtype, and histologic grade.

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.

Subtypes of Sarcomas
The most common subtypes of sarcoma include:

• Angiosarcoma Malignant tumor that resembles blood or lymphatic vessels
• Chondrosarcoma Tumor of cells that form cartilage
• 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.

Sarcobase

Created by University of Washington medical oncologist, Dr. Ernest Conrad, Sarcobase helps in researching this rare form of cancer. To read more about Sarcobase, click here.