Soft tissue sarcomas are rare cancerous tumors that develop in the tissues that support and surround your bones and organs. (Think muscles, tendons and fat cells.) Soft tissue sarcomas usually develop in your arms, legs, chest and the back of your belly, or retroperitoneum.
Soft tissue sarcomas are rare cancerous tumors in the tissues that support and surround your bones and organs. (Think muscles, tendons, fat and skin). You may develop soft tissue sarcomas anywhere but they usually appear in your arms, legs, chest and in the space behind your belly (retroperitoneum).
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No, they aren’t. The American Cancer Society estimates about 13,400 adults and children will learn that they have soft tissue sarcoma in 2023. Soft tissues sarcomas represent 1% of all cancers in adults. They represent 7% of all cancers in children up to age 15 and 3% of all cancers in children age 14 and younger.
There are 70 different types of soft tissue sarcoma. Some soft tissue sarcomas are more common in adults than in children and adolescents (older children between ages 15 and 19).
According to the American Cancer Society, the most common soft tissue sarcomas in adults are:
The most common soft tissue sarcomas in teenagers and young adults are:
Soft tissue sarcoma can be a serious medical issue. Like many forms of cancer, healthcare providers have more success treating soft tissue sarcomas if they diagnose the tumor before it spreads. Without treatment, soft tissue sarcomas may spread (metastasize) and affect other areas of your body.
Many soft tissue sarcoma symptoms are similar to other, less serious conditions. You should contact a healthcare provider if you have:
A soft tissue sarcoma in your leg or arm may look like a lump under your skin. It may look like the kind of lump or bump you’d get from smacking your leg or arm against a hard object like a table leg.
The difference between that kind of lump or bump is that soft tissue sarcomas may not hurt or bruise like a bump from an injury. Soft tissue sarcomas also don’t go away like bumps from injuries. Instead, they may get larger. Sometimes they start to hurt.
You may also have soft tissue sarcomas in your organs, like the back of your belly or the smooth muscles in your intestines. You won’t see those kinds of soft tissue sarcomas.
Researchers are still unraveling what causes soft tissue sarcomas. They’ve found some potential risk factors such as certain inherited disorders and activities. A risk factor is anything that increases the risk you’ll get sick. (Having a risk factor doesn’t mean you’ll get sick. It means you could get sick.)
Inherited disorders happen when people inherit genetic mutations (changes in their genes) that affect how their bodies work. Your provider may recommend genetic testing if your family members have certain inherited disorders. Inherited disorders that increase soft tissue sarcoma risk include:
Other risk factors include:
Healthcare providers will ask you about your symptoms, specifically unusual lumps or bumps on your body. They’ll do a physical examination. They may do several tests, including:
Yes, they do. Providers use cancer staging systems to develop treatment plans and prognoses (what you can expect if you have a soft tissue sarcoma). Providers consider the following factors in staging soft tissue sarcomas:
Soft tissue sarcomas have four stages (Stage I to Stage IV) that combine information about tumor size, location and activity, and tumor grade. There are four grades for soft tissue sarcoma (GX to G3). In general, the lower the tumor’s grade, the better the prognosis. Stage groups are:
Treatments vary depending on factors such as tumor type, where it’s located and the tumor stage. In general, providers use surgery to treat small soft tissue sarcomas that haven’t spread. They may combine surgery with medical treatments, including:
There’s no known way to prevent soft tissue sarcoma. If you know you have soft tissue sarcoma risk factors, ask a healthcare provider what symptoms may be signs you have the condition. That way, you and your provider can take steps to treat the condition before tumors spread.
That depends. The most common treatment is surgery to remove tumors. If a surgeon can remove a tumor before it grows and spreads, they may say they’ve cured the condition. But soft tissue sarcomas can come back (recur) after surgery and other treatment.
Survival rates are estimates based on the experiences of large groups of people. What’s true for the people in those groups may not be true for you. If you have questions about your survival rate, ask your healthcare provider to explain what you may expect.
Overall, experts estimate about 65% of adults with soft tissue sarcoma are alive five years after diagnosis.
Survival rates for soft tissue sarcoma in children and adolescents vary depending on the soft tissue sarcoma type. About 70% of people with rhabdomyosarcoma are alive five years after diagnosis. Ewing sarcoma of soft tissue survival rates vary.
Overall, 76% of children younger than age 15 are alive five years after diagnosis. An estimated 59% of adolescents (ages 15 to 19) are alive five years after diagnosis.
If you have — or your child has — soft tissue sarcoma, the following suggestions may be helpful:
In general, you’ll have follow-up appointments after treatment so your provider can monitor your overall health and your specific condition.
Ask your healthcare provider what symptoms may indicate you need immediate medical attention, including what to do if you’re having trouble managing treatment side effects.
A note from Cleveland Clinic
Having a rare cancer like soft tissue sarcoma may make you feel as if you’re traveling an unfamiliar road without a map to guide you home. You know you need information so you can take steps to get well, but you may be frustrated if you can’t find accurate information about rare cancers. You may have questions for which there aren’t immediate and clear answers.
It may help to know you’re not alone on the unfamiliar road that is rare cancer. Your healthcare team understands what you’re going through. They’ll do everything they can to help you find answers, like explaining your diagnosis in terms you understand, outlining treatment options so you feel confident about treatment decisions or helping you map out your life after you finish treatment.
Last reviewed by a Cleveland Clinic medical professional on 01/27/2023.
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