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Radiation therapy for melanoma

Radiation therapy uses high-energy rays or particles to destroy cancer cells. Radiation may be used for melanoma:

  • to treat lymph nodes following surgery (adjuvant therapy) to reduce the risk of relapse or recurrence in the lymph node basin
  • to relieve pain or to control the symptoms of advanced melanoma (palliative radiation therapy)

Radiation therapy is commonly given as a series of short sessions from Monday to Friday with a rest at the weekend. Each treatment takes about 10–15 minutes. The amount of radiation given during treatment, and when and how it is given, will be different for each person.

External beam radiation therapy

Melanoma is usually treated with external beam radiation therapy. A machine directs radiation to the tumour and some of the surrounding tissue.

Following surgery to remove lymph nodes, people with a high risk of recurrence may be given high-dose radiation therapy. This includes people with:

  • microscopic evidence of extension of the cancer outside of the lymph node (extranodal spread)
  • microscopic evidence of residual disease in lymph nodes
  • extensive nodal disease (where complete resection is not likely)
  • bulky nodal disease (enlarged lymph nodes) greater than 3 cm in diameter that was completely removed
  • 3 or more positive lymph nodes

Radiation therapy may be used to relieve pain and treat symptoms of melanoma that has spread to:

  • distant parts of the skin or lymph nodes
    • Radiation therapy can help reduce the size of skin nodules or lymph nodes and relieve pain.
  • bones
    • Radiation therapy to the bone may be used to reduce pain and help to strengthen bones.
  • brain
    • Radiation therapy to the brain can help to shrink brain metastases and relieve symptoms.
  • lungs
    • Radiation therapy to the lungs can help relieve breathlessness.

See a list of questions to ask your doctor about radiation therapy.


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