Radiation therapy for melanoma skin cancer

Radiation therapy uses high-energy rays or particles to destroy cancer cells.

Some people with melanoma skin cancer have radiation therapy. Your healthcare team will use what they know about the cancer and about your health to plan the type and amount of radiation therapy, and when and how it is given.

You may have radiation therapy to:

• destroy cancer cells
• destroy cancer cells left behind after surgery to reduce the risk that the cancer will come back (recur) (called adjuvant therapy)
• relieve pain or control the symptoms of metastatic melanoma (called palliative therapy)

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

External radiation therapy may be used after surgery to lower the risk of the cancer coming back in the same area where it was removed (local recurrence). It is mainly used for certain cases of early-stage or locoregional melanoma if:

• cancer cells are found in the tissue removed around the tumour during surgery (called a positive surgical margin), but more surgery is not possible
• the lymph nodes removed with surgery have high-risk features, such as multiple lymph nodes in one area of the body have cancer in them

External radiation therapy may be offered for melanoma that has spread to other parts of the body (called metastatic melanoma). It can be given to the bone, brain, lung, liver or pelvis to treat the metastasis or to control symptoms (called palliative therapy).

Stereotactic radiation therapy is a special type of external radiation therapy that may be used when small areas of cancer are found and need to be treated. It delivers a high dose of radiation to a very specific area of the body with only a few radiation treatments.

External radiation therapy is usually given once a day for several weeks. How long treatment is given depends on many factors, such as the size and location of the cancer, the dose of radiation and your overall health.

During radiation therapy, your healthcare team protects healthy cells in the treatment area as much as possible. Side effects of radiation therapy will depend mainly on the size of the area being treated, the specific area or organs being treated, the total dose of radiation and the treatment schedule. 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 melanoma:

• skin problems, such as redness and irritation
• fatigue
• hair loss in the area being treated
• sore mouth and throat if radiation is aimed at the head or neck
• lymphedema, if radiation is aimed under the arm or at the groin

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.