Soft tissue sarcoma (STS) is cancer that forms in the soft tissue of the body. Soft tissue connects, supports, or surrounds other body parts. In adults, STS is rare.

There are many different types of soft tissue cancers. The type of sarcoma depends on the tissue it forms in:

• Muscles
• Tendons
• Fat
• Blood vessels
• Lymph vessels
• Nerves
• Tissues in and around joints

The cancer can form almost anywhere, but is most common in the:

• Head
• Neck
• Arms
• Legs
• Trunk
• Abdomen

STS; Leiomyosarcoma; Hemangiosarcoma; Kaposi's sarcoma; Lymphangiosarcoma; Synovial sarcoma; Neurofibrosarcoma; Liposarcoma; Fibrosarcoma; Malignant fibrous histiocytoma; Dermatofibrosarcoma; Angiosarcoma

It is not known what causes most sarcomas. But there are certain risk factors:

• Some inherited diseases, such as Li-Fraumeni syndrome
• Radiation therapy for other cancers
• Exposure to certain chemicals, such as vinyl chloride or certain herbicides
• Having swelling in the arms or legs for a long time (lymphedema)

In early stages, there are often no symptoms. As the cancer grows, it may cause a lump or swelling that keeps growing over time. Most lumps are not due to cancer.

Other symptoms include:

• Pain, if it presses on a nerve, organ, blood vessel, or muscle
• Blockage or bleeding in the stomach or intestines
• Breathing problems

Surgery is the most common treatment for STS.

• In early stages, the tumor and some healthy tissue around it is removed.
• Sometimes, just a small amount of tissue needs to be removed. Other times, a wider area of tissue must be removed.
• With advanced cancers that form in an arm or leg, surgery may be followed by radiation or chemotherapy. Rarely, the limb may need to be amputated.

You also may have radiation or chemotherapy:

• Used before surgery to help shrink the tumor to make it easier to remove the cancer
• Used after surgery to kill any remaining cancer cells

Chemotherapy may be used to help kill cancer that has metastasized. This means it has spread to different areas of the body.

Cancer affects how you feel about yourself and your life. You can ease the stress of illness by joining a cancer support group. Sharing with others who have had the same experiences and problems can help you feel less alone.

Ask your provider to help you find a support group for people who have been diagnosed with STS.

The outlook for people whose cancer is treated early is very good. Most people who survive 5 years can expect to be cancer-free at 10 years.

Complications include side effects from surgery, chemotherapy, or radiation.

See your provider about any lump that grows in size or is painful.

The cause of most STSs isn't known and there is no way to prevent it. Knowing your risk factors and telling your provider when you first notice symptoms can increase your chance of surviving this type of cancer.

Published Date: August 15, 2022
Published By: Todd Gersten, MD, Hematology/Oncology, Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. Editorial update 02/14/2023.

Contreras CM, Heslin MJ. Soft tissue sarcoma. In: Townsend CM Jr, Beauchamp RD, Evers BM, Mattox KL, eds. Sabiston Textbook of Surgery. 21st ed. St Louis, MO: Elsevier; 2022:chap 32.

National Cancer Institute website. Adult soft tissue sarcoma treatment (PDQ) - health professional version. www.cancer.gov/types/soft-tissue-sarcoma/hp/adult-soft-tissue-treatment-pdq#section/all. Updated December 16, 2022. Accessed February 14, 2023.

Van Tine BA. Sarcomas of soft tissue. In: Niederhuber JE, Armitage JO, Kastan MB, Doroshow JH, Tepper JE, eds. Abeloff's Clinical Oncology. 6th ed. Philadelphia, PA: Elsevier; 2020:chap 90.