What is photodynamic therapy (PDT) for skin cancer?
This involves application of a sensitising cream for 3 hours followed by exposure to a special red light for 8 minutes. It is the best available non-surgical treatment for skin cancers but is only appropriate for certain superficial and low-grade lesions.
How does photodynamic therapy (PDT) work for skin cancer treatment?
In photodynamic therapy (PDT), a photosensitising cream is applied to the skin. This is absorbed preferentially by certain structures in the skin, such as hair follicles, oil glands, bacteria, and cancerous or pre-cancerous cells. One to three hours later the area is illuminated with a high-intensity light or laser. This causes a photochemical reaction in the skin, resulting in destruction of the targeted tissue, while leaving surrounding skin relatively unharmed.
What types of conditions can be treated with PDT?
Photodynamic therapy is effective in the treatment of actinic keratoses (pre-cancerous sun spots), some types of skin cancer, sun-damaged skin, acne, and oily skin with sebaceous gland enlargement.
Is PDT uncomfortable?
During PDT the skin is washed and the activated substance is applied. During therapy, a burning sensation may occur and local anesthesia may be used to minimise this. Following treatment, there may be some transient itching and burning. Most patients experience minimal discomfort but the occasional patient may experience a strong burning sensation. Paracetamol is given to all patients one hour prior to the illumination
Photosensitivity after treatment
After PDT, a small amount of activated substance remains in the skin for 24 to 48 hours. Sunlight and even indoor light may activate this and cause excess redness and itching. For this reason strict sun avoidance is necessary for 24-48 hours after the procedure. Normal sun protection such as use of sunscreen and a hat is required for the week following the procedure.
