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Non-melanoma skin cancer

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Potential side effects of radiation therapy for non-melanoma skin cancer

Side effects can occur with any type of treatment for non-melanoma skin cancer, but not everyone has them or experiences them in the same way. Side effects of radiation therapy will depend mainly on the:

  • size of the area being treated
  • specific area being treated
  • total dose
  • treatment schedule

Radiation therapy damages cancer cells, but healthy cells in the treatment area can also be damaged, even though steps are taken to protect them as much as possible. Different cells and tissues in the body tolerate radiation differently.

Side effects can happen any time during, immediately after or a few days or weeks after radiation therapy. Most side effects go away after radiation therapy is finished. Late side effects can occur months or years after radiation therapy. Some side effects may last a long time or be permanent.

It is important to report side effects to the healthcare team. Many side effects can be relieved by medications, a change in diet or other measures. Doctors may also grade (measure) how severe certain side effects are. Sometimes radiation therapy treatments need to be adjusted if side effects are severe.

Skin reactions

Most skin reactions occur within the first 2 weeks of receiving radiation treatment. They usually go away a few weeks after treatment, but some skin changes can be permanent. Some people do not experience any skin reactions with radiation therapy. General skin reactions to radiation therapy include:

  • redness
  • itching
  • dryness or flaking
  • moistness
  • peeling
  • tenderness or soreness
  • scarring

Once treatment is finished, the skin may become crusty and form a scab. When the scab falls off, there will be healthy skin underneath. This skin will be more sensitive to sun in the future.

Sometimes skin changes occur after radiation is finished and become long-term (chronic) problems. The skin over the treated area can become thinner and appear:

  • darker or tanned (because the cells that produce skin pigment are affected)
  • smooth, tight and shiny
  • red or flushed (because small blood vessels are widened)

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Hair loss

Hair loss (alopecia) only occurs in the area being treated. Thinning or loss of hair can occur in any area where radiation has been directed. The extent of hair loss and regrowth varies from person to person and depends on the dose of radiation.

Hair loss can begin 2–3 weeks after radiation therapy starts. Smaller doses of radiation usually result in temporary hair loss, but permanent hair loss is more common at higher doses. When hair regrows, usually about 3–6 months after radiation treatment is finished, the colour or texture may be different and it may grow back thinner or patchy.

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Second cancers

A very small number of people develop a second non-melanoma skin cancer caused by radiation therapy. The benefit of treating a person’s cancer usually far outweighs the risk of developing a second cancer from radiation therapy. A second cancer can develop a few years after radiation treatment, but most occur 10–20 years or more after treatment.

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