Clinical and research applications of photodynamic therapy in dermatology: experience of the Scottish PDT Centre

Background and Objectives: The Scottish PDT Centre has carried out 3,442 treatments on 762 patients with superficial skin lesions, especially superficial basal cell carcinoma (sBCC), Bowen's disease (BD) and actinic keratosis (AK). Study Design Materials and Methods: The article reviews our experience of various light sources and associated dosimetry; thereafter we discuss clinical outcome followed by some of our research studies in clinically important areas. Results: We show that improved dosimetry is required to ensure an optimal light dose is delivered to the tumour. We have shown that photosensitizers and proteins interact in such a way that their photophysical and photochemical properties are modified. We have also demonstrated the presence of DNA strand breaks with two different photosensitizers, but there is no evidence that PDT is significantly mutagenic in clinical practice. Conclusions: In our experience, topical PDT is generally well tolerated and is an effective treatment of sBCC, BD, AK, field change and lesions at sites of poor healing.