Radiation therapy for soft tissue sarcoma

Radiation therapy uses high-energy rays or particles to destroy cancer cells. Radiation therapy is usually used to treat soft tissue sarcoma. Your healthcare team will use what they know about the cancer and about your health to plan the type and amount of radiation, and when and how it’s given.

You may have radiation therapy to:

• kill cancer cells before surgery (called neoadjuvant therapy)
• destroy cancer cells left behind after surgery (called adjuvant therapy) to reduce the risk that the cancer will come back (recur)
• relieve pain or control the symptoms of advanced soft tissue sarcoma (called palliative therapy)

Radiation therapy and chemotherapy may be given during the same time period to treat soft tissue sarcoma. This is called chemoradiation.

The following types of radiation therapy are used to treat soft tissue sarcoma.

During external radiation therapy, a machine directs radiation through the skin to the tumour and some of the tissue around it. External radiation therapy is also called external beam radiation therapy.

Doctors may use the following external radiation techniques to accurately target the area to be treated and spare as much surrounding normal tissue as possible.

Intensity-modulated radiation therapy (IMRT) delivers radiation from many different angles to treat the entire tumour. In addition to shaping and aiming the radiation beams, IMRT allows the radiation oncologist to adjust the strength (intensity) of the individual beams. This reduces the dose of radiation reaching nearby normal tissue while allowing a higher dose to be delivered to the tumour. Itʼs useful for treating tumours in hard-to-reach areas.

Brachytherapy is a type of internal radiation therapy. A sealed container of a radioactive substance, called an implant, gets placed right into the tumour or in the area where the tumour was removed. The radiation kills the cancer cells over time.

Brachytherapy is usually given as a high-dose-rate (HDR) brachytherapy. HDR brachytherapy delivers a higher dose of radiation in a short period of time.

Side effects of radiation therapy will depend mainly on the size of the area being treated, the specific area being treated, the total dose of radiation and the treatment schedule. Your healthcare team protects healthy cells in the treatment area as much as possible. Tell your healthcare team if you have side effects that you think are from radiation therapy. The sooner you tell them of any problems, the sooner they can suggest ways to help you deal with them.

These are common side effects of radiation therapy for soft tissue sarcoma:

• fatigue
• nerve damage
• skin problems in the area being treated, such as dry skin or redness
• weakness and stiff joints in a treated limb
• thickening and scarring of connective tissue (called fibrosis)

When radiation therapy is given before surgery, common side effects include:

• slow wound healing
• infection
• a collection or pool of blood under the skin (hematoma)

Find out more about radiation therapy and side effects of radiation therapy. To make the decisions that are right for you, ask your healthcare team questions about radiation therapy.