Sarcoma: Overview

This section has been reviewed and approved by the Cancer.Net Editorial Board, 01/2013

ON THIS PAGE: You will find some basic information about this disease and the parts of the body it may affect. This is the first page of Cancer.Net’s Guide to Sarcoma. To see other pages, use the menu on the side of your screen. Think of that menu as a roadmap to this full guide.

Cancer begins when normal cells change and grow uncontrollably, forming a mass called a tumor. A tumor can be benign (noncancerous) or malignant (cancerous, meaning it can spread to other parts of the body).

About sarcoma

Sarcoma can start in any part of the body, such as the bone or soft tissue. About 60% of soft tissue sarcomas begin in an arm or leg, 30% start in the trunk (torso) or abdomen, and 10% occur in the head or neck. Both children and adults can develop a sarcoma, but it is rare in adults, accounting for about 1% of all adult cancers. However, sarcoma in general represents about 15% of all cancers in children.

This section covers sarcoma of the soft tissues. Learn more about sarcoma that starts in a bone.

About soft-tissue sarcoma

Soft-tissue sarcomas (STS) are a group of cancers that begin in the tissues that support and connect the body, such as fat cells, muscle, nerves, tendons, the lining of joints, blood vessels, or lymph vessels. As a result, STS can occur almost anywhere in the body. When an STS is small, it can go unnoticed, since it does not usually cause problems early on. However, as an STS grows, it can interfere with the body's normal activities.

Because there are several different types of STS, it is more of a family of related diseases rather than a single, specific disease. The specific types of sarcoma are often named according to the normal tissue cells they most closely resemble (see below). This is different from most other types of cancer, which are usually named for the part of the body where the cancer began. Some sarcomas do not look like any type of normal tissue and are thought to come from stem cells, which are special cells that can mature into specific tissues or organs.

Name of Sarcoma

Related Normal Tissue Type

Angiosarcoma

Blood or lymph vessels

Ewing Family of sarcomas (peripheral primitive neuroectodermal tumor, PNET)

 

 

No obvious related normal tissue; may be a tumor of stem cells

Fibrosarcoma

Fibrous tissue (tendons and ligaments)

Gastrointestinal stromal tumor (GIST)

Specialized neuro-muscular cells of the digestive tract

Kaposi sarcoma

Blood vessels

Leiomyosarcoma

Smooth muscle

Liposarcoma

Fat tissue

Myxofibrosarcoma (myxoid malignant fibrous histiocytoma, MFH)

 

Connective tissue

Malignant peripheral nerve sheath tumor (MPNST, also known as neurofibrosarcoma)

Cells that wrap around nerve endings similar to how insulation wraps around a wire

Pleomorphic sarcoma, not otherwise specified (NOS; often referred to in the past as malignant fibrous histiocytoma, MFH)

 

No obvious related normal tissue; may be a tumor of stem cells

Rhabdomyosarcoma

Skeletal muscle

Synovial sarcoma

No obvious related normal tissue; may be a tumor of stem cells

The list above is not complete, but several of the most common types are listed. Experts have found many types and subtypes of sarcomas. Pathologists (doctors who specialize in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease) are now trying to find new ways to quickly determine a tumor's subtype, as this helps determine treatment. Looking at a tumor's abnormal genetics may help determine its characteristics and predict which treatments will be most effective. For at least two types of sarcoma, GIST and dermatofibrosarcoma protuberans (DFSP), major advances have been made in a type of treatment called targeted therapy (see Treatment). 

Grade is another characteristic pathologists use to describe sarcomas. The grade helps predict how aggressive the sarcoma is likely to be, meaning how likely it will grow and spread to another part of the body. A low-grade tumor generally grows more slowly and often stays in the area where it started. A high-grade tumor is more likely to spread to other places, called metastasis. Learn more about grade in the Staging section.

Find out more about basic cancer terms used in this section.

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