Photodynamic therapy in dermatology.

Photodynamic therapy is a new modality of therapy being used for the diagnosis and treatment of many tumors. It is now being increasingly used for skin tumors and other dermatological disorders. With its range of application it is certainly the therapy of the future. Its mechanism of action is by the Type II photo-oxidative reaction. The variables are the photosensitizer, the tissue oxygenation and the light source. It has been used to treat various disorders including Bowen's disease, actinic keratoses, squamous cell carcinomas, basal cell carcinomas, and mycosis fungoides. The side-effects are fortunately mild and transient. Newer photosensitizers like methyl aminolevulinate hold a lot of promise for better therapy.