Photodynamic therapy for non-melanoma skin cancers and pre-cancerous skin lesions

Photodynamic therapy, also known as PDT, is a technique for treating early localised skin cancers and sun-damaged skin which may one day turn cancerous (pre- cancers). 

PDT involves applying a special cream to the affected area of skin followed by shining a highly targeted light to destroy cancer cells while leaving nearby healthy cells undamaged.

Which cancers can photodynamic therapy treat?

PDT can be used to treat various skin conditions including:

  • Basal cell carcinomas (BCCs)
  • Bowen’s disease (squamous cell carcinoma in situ) -  pre-cancerous condition
  • Actinic (solar) keratoses -  sun damage lesions,  pre-cancerous condition

At present, photodynamic therapy cannot be used to treat malignant melanomas (a rare type of skin cancer), although the technology is constantly evolving.

How does photodynamic therapy work?

Photodynamic therapy involves the application of a photosensitiser (light sensitive) cream onto the affected skin.  When light of a certain wavelength is shone onto it, the photosensitiser is activated.  This affects the oxygen molecules within the cancerous skin cells, causing them to destroy the abnormal cells.

The photosensitiser alone is harmless, as is the light. Only when the 2 are combined will they treat the abnormal area of your skin.

The photodynamic therapy process:

  • You will come to The London Clinic as an outpatient appointment
  • Cream containing the photosensitive agent is applied to the area of skin to be treated and covered with a dressing.
  • The cream takes 3 hours to be absorbed. During this time you may stay at the hospital or you may leave and return to the hospital later
  • Light from a special LED lamp is then shone on the target area for up to 10 minutes.
  • The treated area is dressed to protect it from exposure to light.

Treatment can be repeated a week apart dependent on the lesion.

After photodynamic therapy, the affected area will form a scab whilst its healing. The scab will then drop off, leaving healed skin with no scarring.

The photosensitive chemicals used will vary depending on the location and type of cancer.

Unlike chemotherapy or radiotherapy, photodynamic therapy skin cancer treatment is quick and easy and has very few side effects. It can produce minor discomfort, such as a burning or tingling sensation, but this can be relieved with paracetamol, a local anaesthetic or/ and with a cooling machine such as the cryocooler available in our Clinical Procedure Rooms.