Ambulatory photodynamic therapy: a new concept in delivering photodynamic therapy

Background: Photodynamic therapy (PDT) has been shown to be effective in treating Bowen's disease, superficial basal cell carcinoma and actinic keratosis. Objectives: To investigate the feasibility of delivering PDT using a portable light-emitting diode device. Methods: A prototype diode array, comprising 37 AlGaInP diodes cast in epoxy with a diffuser, and driven by a battery pack, was designed and constructed. A pilot study was carried out in five patients with histologically proven Bowen's disease who were referred for PDT with 5-aminolaevulinic acid. They were all treated in the hospital-based dermatology PDT suite such that each received the same level of supervision as patients receiving PDT with nonambulatory light sources. Patients recorded pain levels. In accordance with our usual practice, patients received two treatments at a 4-week interval. Results: Four of five patients were clear at follow-up (range 6-13 months, median 9). Pain was classified as none or mild in 80% of treatments and moderate in the remainder. Conclusions: There are many potential benefits of ambulatory PDT, including the possibility of a much higher patient throughput, and allowing effective treatment at home. This pilot study provides early promising data of the safety and efficacy of this approach.