What is a benign soft tissue tumour?

A soft tissue tumour is a growth of abnormal cells in the body's soft tissues. These tissues include the muscles, lymph and blood vessels, nerves, and fat. They can also include cartilage and other connective tissues. When a tumour is benign (say "bih-NYN"), that means it's not cancer. Most soft tissue tumours are benign.

Benign tumours don't spread to other tissues and organs. They usually aren't life-threatening. But they can cause problems if they grow too much, press on nerves, or cause pain.

What are some common types of these tumours?

Some common types of benign soft tissue tumours include:

Lipomas.

These tumours form from fat cells. Angiolipomas are a type of lipoma made up of fat and blood vessels.

Nerve sheath tumours.

Tumours on a nerve may include schwannomas and neurofibromas. They might need to be removed.

Benign synovial tumours.

These appear around the tendons, near the knee, hip, elbow, or shoulder. Examples include giant cell tumour of the tendon sheath and synovial chondromatosis.

Hemangiomas.

These are tumours of the blood vessels.

Desmoid tumours.

These tumours commonly appear on the shoulder, chest, back, and thighs.

Nodular fasciitis.

These are most common in the arms. They can grow quickly.

Other types of tumours may appear on the skin, belly, arms and legs, organs, and nerves.

What are the symptoms?

Sometimes a tumour can be felt as a bump under the skin. Or if the tumour is deep enough below the skin, you may not be able to feel it. You may also feel pain near the tumour if it's large or pressing on something.

How are these tumours diagnosed?

Your doctor will ask you about your symptoms and past health and will examine you. A physical exam can help your doctor diagnose some soft tissue tumours.

Your doctor may find a tumour when taking X-rays or other imaging tests for another problem.

If your doctor isn't sure what the growth is and your symptoms could be signs of a tumour, you will get some tests. The tests can help make sure it's not cancer. They can also help your doctor figure out the best treatment for the tumour.

• You may have one or more imaging tests to get a better look at the tumour. These may include:
  • X-rays.
  • Ultrasound tests.
  • CT scan.
  • MRI scan.
• You may need blood tests and lab work.
• You may need a biopsy so a sample of the tumour can be looked at under a microscope. This sample may also be used to test for biomarkers. They will help with planning treatment.

Doctors may also look at other parts of your body for other tumours.

How are they treated?

Some benign soft tissue tumours that aren't causing problems can be watched over time. Some may remain stable or go away on their own. But if the tumour causes pain, is growing larger, or affects your movement, it may need to be removed.

You may also choose to have these tumours removed if they bother you or if you don't like how they look.

Doctors may remove some tumours with surgery. In some cases, other treatments, including medicines, may be used.

Talk with your doctor or specialist about other types of treatments for the tumour. After your treatment, your doctor may want to check the area again to make sure that the growth doesn't come back.