Sarcoma is a rare cancer that starts in the body's connective tissues, often in an arm or leg. It’s the only solid tumor that can occur at any age and in any part of the body. Sarcomas are easier to treat when discovered early, before cancer has spread from its original site.

There are two main types:

• Soft tissue sarcomas start in fat, muscles, nerves, blood vessels and deep skin.
• Bone sarcomas (also called bone cancer) start in bone cells.

What is sarcoma?

Sarcoma is a cancer that starts in the body's connective tissues, such as fat, muscles, nerves and bone. Because these tissues fill the body, a sarcoma can develop anywhere, including in the breast and abdomen. Because a large portion of these tissues exist in the arms and legs, many sarcomas start there.

Who gets sarcoma?

Sarcomas are rare. About 17,000 new cases are diagnosed each year in the U.S., according to the National Cancer Institute. Roughly 225,000 Americans are living with it.

Risk factors include:

Youth: About half of all sarcomas occur before age 40. This may be in part because sarcomas often form during growth spurts.

Family history: Families that have certain rare cancer syndromes are more likely to get sarcomas. OHSU offers expert genetic counseling and testing to help patients and families assess and manage risk.

Other: People who've had radiation therapy, who have a damaged lymph system or who've been exposed to certain chemicals also have a higher risk.

Sarcoma survival rates

Survival statistics are usually expressed by a percentage known as the five-year relative survival rate. This statistic compares your likelihood of surviving five years after diagnosis compared to someone of the same age who doesn't have cancer.

Survival rates depend on the type of sarcoma you have. They are higher when sarcoma starts in an arm or leg. They are also higher if the cancer is caught before it spreads.

Soft tissue sarcoma: The five-year survival rate is 82% if your sarcoma is found before it spreads, according to the American Cancer Society.  Ten-year survival rates are similar. This suggests that those who survive five years are likely to be cured. 

Osteosarcoma: The five-year relative survival rate is 76% if the sarcoma is caught before it spreads.

Chondrosarcoma: The five-year relative survival rate is 91% if the sarcoma is caught before it spreads.

Ewing sarcoma: The five-year relative survival rate is 82% if the sarcoma is caught before it spreads.

It’s important to know that survival rates are averages and can’t predict the outcome for any one patient. It's also important to know that these rates reflect the treatments that were available five or more years ago. 

Symptoms of sarcoma

Most often, these symptoms are not caused by sarcoma. But if they persist and no other condition explains them, talk with your doctor.

Signs and symptoms of a soft tissue sarcoma:

• A lump on an arm or leg, often not painful, that grows over weeks or months
• Pain in the abdomen
• Blood in your vomit or stool, or stools that are black and tarry

Signs and symptoms of a bone sarcoma:

• Pain in the affected bone, first only at night or when using that bone, later frequently
• Lump or mass, depending on the tumor’s location
• Rarely, fractures caused by a weakened bone

Soft tissue sarcoma

Soft tissue sarcoma makes up about 80% of sarcoma cases. It also comes in dozens of types. Some of the most common ones are:

• Angiosarcoma: This type forms in blood vessels or vessels of the lymph system, sometimes after treatment with radiation therapy.
• Desmoid tumor: A tumor that grows inside the connective tissue in your body. It is not technically cancer, but can damage tissue and cause pain.
• Fibrosarcoma: This type develops in fibrous tissue in the arms, legs or trunk.
• Leiomyosarcoma: This type develops in smooth muscle cells, such as in the wall of the uterus, stomach or intestine.
• Liposarcoma: This type forms in fatty tissue and can occur anywhere in the body.
• Malignant peripheral nerve sheath tumor: This aggressive tumor forms in a nerve’s protective covering. It’s also called an MPNST.
• Rhabdomyosarcoma: This type is usually found only in children, with about half of cases diagnosed in patients younger than 10. It usually develops in muscles that are attached to bone and that you can control.
• Tenosynovial giant cell tumor (TGCT): A rare tumor that forms in the tissue around a joint where two bones meet. It is not technically cancer, but can damage or destroy a joint.
• Undifferentiated pleomorphic sarcoma: This type usually forms in arms or legs and occurs most often in older adults. It’s usually found in soft tissue but can also develop in bone. It can form in body parts previously treated with radiation therapy.

Bone sarcoma

The most common types are:

• Osteosarcoma: This is the most common bone sarcoma. It starts in bone cells and most often occurs in ages 10 to about 30.
• Chondrosarcoma: The second most common type starts in cartilage cells and is rare in children.
• Ewing sarcoma of the bone: The third most common type often starts in the hip bone, the ribs and the legs. It mostly affects children and teens. One type of Ewing sarcoma begins in soft tissue.

Sarcoma staging

Staging plays an important role in treatment decisions by determining factors such as:

• Whether your cancer has spread
• If so, how much
• How aggressive it is likely to be

Soft tissue sarcomas

Cancer experts have changed how they stage soft tissue sarcomas because they are so complex. Your cancer will be staged based on factors that include:

• The type of soft tissue sarcoma
• The part of the body it started in
• The size of the tumor
• Whether cancer has spread to lymph nodes or other parts of the body
• The cancer’s grade:
  • How normal or abnormal cells look under a microscope
  • How many cells are dividing (mitotic count)
  • How much dead tissue (necrosis) the cancer contains

Bone sarcomas

Generally, cancer in Stages I through III has not spread outside the bone where it started.

Stage I: The tumor is low grade, meaning its cells don't look much different from normal cells; it’s not growing fast; and it doesn’t contain much dead tissue. It is also confined to the area where it started. In the spine, the tumor is confined to nearby vertical segments of the spine. For the pelvis, the tumor is confined to two pelvic segments.

Stage II: The tumor remains where it started but has a higher grade, meaning cells look more abnormal, and the tumor is growing faster and contains more dead tissue.

Stage III: The tumor is larger or has spread to more bone areas near where it started. It’s also higher grade.

Stage IV: The tumor may be of any grade, but cancer has spread outside the bone where it began. In Stage IVA, cancer has spread to a lung. In Stage IVB, cancer has spread to lymph nodes or other parts of the body besides the lung.

Learn more

• Find an OHSU clinical trial for sarcoma
• Read about OHSU’s cancer registries, including for sarcoma. Registries offer a chance to help research and receive updates.
• Soft Tissue Sarcoma, National Cancer Institute
• Bone Cancer, National Cancer Institute
• Soft Tissue Sarcoma, American Cancer Society
• Bone Cancer, American Cancer Society
• Osteosarcoma, American Cancer Society
• Ewing Family of Tumors, American Cancer Society
• Sarcoma Foundation of America
• Northwest Sarcoma Foundation
• National Leiomyosarcoma Foundation