What is Soft Tissue Sarcoma?

Soft tissue sarcoma (STS) is a rare form of cancer that begins in the soft tissues of the body, such as muscles, tendons, fat, lymph and blood vessels, and nerves. Although these tumors can develop anywhere in the body, they are more commonly found in the arms, legs, chest, abdomen, head, and neck.

In the United States:

Approximately 13,040 new soft tissue sarcomas will be diagnosed in adults and children each year.
Males are slightly more likely to develop soft tissue sarcoma; in 2018, there were approximately 7,370 new cases in males in 2018 and 5,670 new cases in females.
About 5,150 Americans will die of soft tissue sarcoma each year.
It was expected that 2,770 males and 2,380 females would die from soft tissue sarcoma in 2018.
The most common forms of soft tissue sarcoma are undifferentiated pleomorphic sarcoma, liposarcoma, and leiomyosarcoma.
Sarcomas account for over 15% of all childhood cancers and 1% of all adult cancers.
Although sarcoma can begin in any part of the body, 60% start in an arm or leg, 30% in the torso or abdomen, and 10% in the head or neck.
About 58% of sarcomas are localized at diagnosis (tumor has not spread).
About 18% of sarcomas are regional (cancer cells have spread to nearby lymph nodes or tissue).
About 14% of sarcomas are distant or metastatic (cancer cells have spread to distant tissues, such as the lungs).

Overall, the survival rate for soft tissue sarcoma is 50% and that number is expected to increase as newer treatments are developed. Your treatment options and chance of recovery (prognosis) depend on several factors, including:

The type of soft tissue sarcoma you have
The size and stage of the tumor when found
How fast the cancer cells are growing and dividing
Where the tumor is located
If the tumor can be surgically removed
Your age and general health
Whether the cancer has returned

Speak with your doctor about your treatment options and prognosis based on your specific cancer.

Types of Soft Tissue Sarcoma

There are more than 50 types of soft tissue sarcoma, and knowing your type will help determine your treatment options and prognosis. Some common soft tissue sarcoma types are found below.

Liposarcoma is a type of soft tissue sarcoma that begins in the fatty tissues of the body. It is usually found in the limbs and abdomen. These tumors tend to become very large and the first sign is usually a growing lump on the arm or leg, or swelling of the stomach. Liposarcomas are usually detected first by an MRI or CT scan, followed by a biopsy. The main treatment for liposarcoma is surgery, but radiation, chemotherapy or other drugs may be recommended. Liposarcomas often come back months to decades after first diagnosis and follow-up care is important to monitor for the return of cancer.

Leiomyosarcoma begins in the smooth muscle tissue surrounding hollow organs, such as the uterus, bladder, stomach, veins, and arteries. Many people do not experience signs or symptoms until the tumor is very large. Significant weight gain in the abdomen is often the first sign.

Synovial sarcoma is a rare cancer that is more commonly diagnosed in patients under 40. It usually occurs in the arms or legs, but it can be found in any part of the body and in people of all ages. The main sign of synovial sarcoma is a painful lump in the arm or leg.

Undifferentiated pleomorphic sarcoma (UPS) is also known as malignant fibrous histiocytoma or myxofibrosarcoma. UPS can occur anywhere in the body but it is usually found in the back of the abdomen, arms, legs, and thighs. These tumors tend to grow quickly and can spread to other parts of the body, such as the lungs.

Malignant peripheral nerve sheath tumors (MPNSTs) are rare and highly aggressive tumors that develop in nerve cells. The most common sign is a painful lump. Approximately one third of MPNSTs are associated with neurofibromatosis, a genetic condition.

Gastrointestinal stromal tumors (GISTs) usually develop in the stomach, tend to be large in size, and can spread to other parts of the body. GIST tumors are usually discovered during an endoscopy or CT scan for an unrelated condition. Signs of GIST may include blood in the stool or vomit, abdominal pain, feeling tired, feeling full, and trouble, or pain with swallowing. It is usually treated with surgery and medications. Radiation is rarely used.

References:

National Cancer Institute. Soft Tissue Sarcoma – Patient Version. https://www.cancer.gov/types/soft-tissue-sarcoma. Accessed March 14, 2019.

American Cancer Society. Survival by Stage of Soft Tissue Sarcoma. https://www.cancer.org/cancer/soft-tissue-sarcoma/detection-diagnosis-staging/survival-rates.html. Accessed March 14, 2019.

Cancer.net. Sarcoma, Soft Tissue. https://www.cancer.net/cancer-types/sarcoma-soft-tissue. Accessed March 14, 2019.

Canadian Cancer Society. Prognosis and survival for soft tissue sarcoma. www.cancer.ca/en/cancer-information/cancer-type/soft-tissue-sarcoma/prognosis-and-survival/?region=on. Accessed March 14, 2019.