What is soft tissue sarcoma?

A soft tissue sarcoma (STS) is a rare cancer. It can develop in the cells of tissues that support, connect, surround and protect the organs in the body. These tissues include:

  • fat
  • muscle
  • nerves
  • fibrous tissues
  • tendons and ligaments
  • blood vessels.

The most common areas for soft tissue sarcoma to start are the arms and legs. But it can develop anywhere in the body, including the:

  • womb (uterus)
  • stomach
  • small or large bowel (intestines)
  • area at the back of the tummy (abdomen) called the retroperitoneum
  • skin
  • head and neck.

Sarcoma is more common in people over 30. Certain types of sarcoma can develop in children and teenagers. The symptoms and treatment may be different from an adult with the same sarcoma. The Children’s Cancer and Leukaemia Group (CCLG) has more information about children's cancers.

Sarcomas can also start in the bone. This is called primary bone cancer. They grow differently from soft tissue sarcomas and are treated differently.

Sometimes it is hard to tell whether a sarcoma has started in soft tissue or bone. Some types, such as Ewing sarcoma, can start in either the bone or the soft tissue. Ewing sarcoma is most common in teenagers.

Booklets and resources

Types of soft tissue sarcoma

There are different types of soft tissue sarcoma. A sarcoma is named after the type of cell it looks like not after the part  he body where it started.

Some sarcomas start from very early, undeveloped cells called stem cells. As they grow, they start to look like a particular tissue.

Your doctor or specialist nurse can tell you more about which type you have. Some types of soft tissue sarcoma are:

There are many other types of soft tissue sarcoma. We have more information about different types of soft tissue sarcoma.

Symptoms of soft tissue sarcoma

Soft tissue sarcoma can start in any part of the body. Often, they do not cause any symptoms until they start pressing on an organ, nerve or muscle. The main symptom of a sarcoma in an arm or leg is a lump or swelling that is:

  • getting bigger
  • bigger than 5cm (2in) – about the size of a golf ball
  • painful or tender.

Most soft tissue lumps are not cancer. But if you notice any of these symptoms, get them checked by your GP. They can arrange a scan.

Symptoms will depend on where the sarcoma starts in the body. For example, sarcoma that starts in the womb (leiomyosarcoma) can cause vaginal bleeding. Different types of sarcoma cause different symptoms.

We have more information about symptoms of soft tissue sarcoma.

Causes of soft tissue sarcoma

The causes of soft tissue sarcomas are not known. There are certain things that can affect the chances of developing a soft tissue sarcoma. These are called risk factors.

Having risk factors does not mean you will get sarcoma, and people without risk factors can still develop it. We have more information about the risk factors and causes of soft tissue sarcoma.

Tests and diagnosis

You usually start by seeing your GP, who will examine you. They may arrange for you to have tests. This may include an ultrasound of the lump. Or they may refer you to see a specialist at the hospital straightaway.

At the hospital the specialist will examine you. They arrange different tests depending on your symptoms. Your doctor and specialist nurse will explain the tests you need. Tests usually include blood tests, ultrasound, and scans.

A doctor or nurse may take samples of tissue from the tumour. This is called a biopsy. The type of biopsy depends on where the lump is and its size. If you are having surgery to remove the tumour, you may not have a biopsy before your operation.

If tests show you have a sarcoma your specialist will arrange further tests. These can help find out more about the size and position of the cancer and whether it has spread.

Tests are also done on the cancer cells to find out more about the type of sarcoma. Other tests check if the cancer cells have any genetic changes or are producing any proteins.

We have more information about tests for soft tissue sarcoma.

Staging and grading of soft tissue sarcoma

The stage of a cancer describes its size and if it has spread from where it started.

A doctor decides the grade of the cancer by how the cancer cells look under the microscope.

This gives an idea of how quickly the cancer may develop. Knowing more about the staging and grading of soft tissue sarcoma helps you and your doctors decide on the best treatment for you.

Treatment of soft tissue sarcoma

Because sarcoma is a rare cancer, you will be treated at a specialist sarcoma unit. A team of specialists will meet to discuss the best possible treatment for you. This is called a multidisciplinary team (MDT).

Your treatment for soft tissue sarcoma depends on a few things, including:

Your cancer doctor or specialist nurse will explain the different treatments and their side effects. They will also talk to you about things to consider when making treatment decisions.

The following treatments may be used to treat soft tissue sarcoma. Most people need a combination of these treatments.

  • Surgery

    Surgery is the most common treatment for soft tissue sarcoma. If you have a bone sarcoma in an arm or leg, it is usually possible to remove the sarcoma with limb-sparing surgery. Very rarely, the best treatment is to remove the whole of the affected limb (amputation). Some people might need reconstructive surgery to repair the area of the surgery.

  • Radiotherapy

    Radiotherapy uses high-energy rays to destroy cancer cells. Radiotherapy may be given before surgery to shrink the cancer, or after surgery, to destroy any remaining cancer cells. It can also be used to relieve symptoms and control sarcoma that has spread or come back. Rarely, when surgery is not possible, it is used on its own.

  • Chemotherapy

    Chemotherapy uses anti-cancer (cytotoxic) drugs to destroy cancer cells. Not everyone has chemotherapy. It depends on the type of sarcoma and the risk of it coming back. It may be given after or before surgery. Chemotherapy can also be given to relieve symptoms and to control sarcoma that cannot be completely removed or has spread.

  • Targeted therapy

    Targeted therapy Targeted therapy uses drugs to find and attack cancer cells. There are different types of targeted therapy, including tyrosine kinase inhibitors (TKIs). Imatinib is a TKI that is often used to treat gastrointestinal stromal tumour (GIST). Some other targeted therapy drugs might be used in some situations to help to control soft tissue sarcoma.

You might have some treatments as part of a clinical trial.

After soft tissue sarcoma treatment

Follow up

After your treatment finishes, you will have regular check-up appointments with your cancer doctor or specialist nurse. You will usually be seen every few months for the first 2 years. Later, you will be seen once a year.

Your cancer doctor and nurse will explain more about your follow-up. It will depend on the type of treatment you had and the risk of the cancer coming back.

Your doctor will examine you. You will usually have regular chest x-rays. Depending on the type of sarcoma you had you may have other x-rays, CT scans or MRI scans of the area where you had the sarcoma. These check for any signs of the cancer coming back so it can be treated straight away.

The most common area for soft tissue sarcoma to spread to is the lungs. If there is only a small amount of cancer in the lungs it may be possible to remove the affected part of the lung.

Possible late effects

Late effects are side effects that do not improve, or that develop years after treatment has finished. Your doctor or nurse will explain any likely late effects of your treatment.

Always tell them if you have any new symptoms, or if side effects are not improving.

Lymphoedema is a swelling of a limb or of another area of the body. It sometimes happens after surgery or radiotherapy to the lymph nodes and might develop months or years after treatment. It is important to protect the skin in the area to reduce the risk of getting an infection. If you have any signs of infection, such as redness or swelling in the treated area, see your GP straight away. There are things you can do to help reduce the risk of lymphoedema.

Body image

If treatment has changed your appearance it can affect how you think and feel about your body. This is called your body image. You may have scars from surgery, or surgery to a limb may have caused changes in how you move. If you have had an arm or leg removed, the change to your body may be difficult to accept and adapt to.

Surgery to the head and neck might sometimes affect speaking or eating. You may need support from a speech and language therapist and a dietitian.

Talk to your nurse if you are finding it difficult to cope with body changes.

Sex life

Cancer and its treatments may affect your sex life and how you feel about yourself sexually. This often gradually improves after treatment. If you are worried talk to your doctor or nurse. You can read about things that can help in our information on cancer and sex.


Some cancer treatments can also affect whether you can get pregnant or make someone pregnant. If you are worried about this, it is important to talk with your doctor before you start treatment.

We have more information about:

Well-being and recovery

Even if you already have a healthy lifestyle, you may choose to make some positive lifestyle changes during and after treatment.

Eating well and keeping active can improve your health and well-being. It can also help your body recover.

Getting support

After finishing treatment, you may still be coping with difficult feelings. Talking to your family and friends or health professionals about how you feel can help to support your well-being.

There are also national support groups that you may find helpful, such as Sarcoma UK.

Macmillan is also here to support you. If you would like to talk, you can:

About our information

  • References

    Below is a sample of the sources used in our soft tissue sarcoma information. If you would like more information about the sources we use, please contact us at cancerinformationteam@macmillan.org.uk

    Gronchi A, Miah AB et al. Soft tissue and visceral sarcomas: ESMO-EURACAN-GENTURIS Clinical practice guidelines for diagnosis, treatment and follow-up. Annals of Oncology, 2021; 32, 11, 1348-1365 [accessed May 2022].

    Casali PG, Blay JY et al. Gastrointestinal stromal tumours: ESMO-EURACAN-GENTURIS Clinical practice guidelines for diagnosis, treatment and follow-up. Annals of Oncology, 2022; 33,1, 20-33 [accessed May 2022].

  • Reviewers

    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by senior medical editor Fiona Cowie, Consultant Clinical Oncologist.

    Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.

The language we use

We want everyone affected by cancer to feel our information is written for them.

We want our information to be as clear as possible. To do this, we try to:

  • use plain English
  • explain medical words
  • use short sentences
  • use illustrations to explain text
  • structure the information clearly
  • make sure important points are clear.

We use gender-inclusive language and talk to our readers as ‘you’ so that everyone feels included. Where clinically necessary we use the terms ‘men’ and ‘women’ or ‘male’ and ‘female’. For example, we do so when talking about parts of the body or mentioning statistics or research about who is affected.

Date reviewed

Reviewed: 01 August 2021
Next review: 01 August 2023

This content is currently being reviewed. New information will be coming soon.

Trusted Information Creator - Patient Information Forum
Trusted Information Creator - Patient Information Forum

Our cancer information meets the PIF TICK quality mark.

This means it is easy to use, up-to-date and based on the latest evidence. Learn more about how we produce our information.