Photodynamic therapy for non-melanoma skin cancer

A few people with non-melanoma skin cancer have photodynamic therapy (PDT). It uses photosensitizer drugs to destroy cancer cells. These drugs make cells sensitive to light.

PDT may be used to treat:

  • basal cell carcinoma (BCC) on the surface of the skin (superficial BCC)
  • squamous cell carcinoma (SCC) in situ
  • actinic keratosis, a precancerous condition of the skin

PDT is most often offered when surgery can’t be done or when how the skin looks is important. In most cases, there is a higher risk of the cancer coming back (recurring) after PDT than after surgery. But with PDT, there is a better chance that the skin will look good. Your healthcare team will consider this when deciding if PDT is right for you.

How PDT is given

PDT is given in 2 stages. First, you are given the photosensitizer drug. It is applied to the abnormal area as a cream. All cells absorb the photosensitizer but it stays in the cancer cells longer than it does in normal cells. The photosensitizer drug used for non-melanoma skin cancer is methyl aminolevulinate (Metvix).

After a certain amount of time, cancer cells containing the photosensitizer are exposed to a low-intensity red light or regular daylight when outside. The photosensitizer in the cancer cells absorbs the light and a chemical reaction kills the cancer cells. Most normal cells are not affected.

Side effects

Side effects can happen with any type of treatment for non-melanoma skin cancer, but everyone’s experience is different. Some people have many side effects. Other people have few or none at all.

Side effects can happen any time during, immediately after or a few days or weeks after PDT. Most side effects go away when treatment is over.

Side effects of PDT for non-melanoma skin cancer caninclude:

  • sensitivity to light of the skin and eyes (called photosensitivity), which usually lasts 4–6 days after treatment or longer
  • pain at the site, including burning and stinging
  • red, itchy skin
  • swelling (edema)

Tell your healthcare team if you have these side effects or others you think might be from PDT. The sooner you tell them of any problems, the sooner they can suggest ways to help you deal with them.

Expert review and references

  • Christensen SR, Leffell DJ . Cancer of the skin. DeVita VT Jr, Lawrence TS, Rosenberg SA. Cancer: Principles and Practice of Oncology. 10th ed. Wolters Kluwer Health/Lippincott Williams & Wilkins; 2015: 92:1314-1336.
  • Drugs and Health Products, Health Canada. Regulatory Decision Summary: Metvix. 2017:
  • National Cancer Institute. Skin Cancer Treatment for Health Professionals (PDQ®). 2015:
  • National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Basal Cell Skin Cancer (Version 1.2015). 2015.
  • National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Squamous Cell Skin Cancer (Version 1.2015). 2015.
  • Sapijaszko M, Zloty D, Bourcier M, Poulin Y, Janiszewski P, Ashkenas J . Non-melanoma skin cancer in Canada chapter 5: management of squamous cell carcinoma. Journal of Cutaneous Medicine and Surgery. 2015.
  • Zloty D, Guenther LC, Sapijaszko M et al . Non-melanoma skin cancer in Canada chapter 4: management of basal cell carcinoma. Journal of Cutaneous Medicine and Surgery. 2015.

Medical disclaimer

The information that the Canadian Cancer Society provides does not replace your relationship with your doctor. The information is for your general use, so be sure to talk to a qualified healthcare professional before making medical decisions or if you have questions about your health.

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