Photodynamic therapy: off-label and alternative use in dermatological practice

Photodynamic therapy (PDT) is a treatment technique that permits the clearance of different skin lesions with high success rates in many dermatological diseases. Worldwide recognized uses for PDT in dermatology include non-melanoma skin cancer, actinic keratoses, acne vulgaris, photorejuvenation, and hidradenitis suppurativa. In the European Union, and in the USA, its indication is for the treatment of nonhyperkeratotic actinic keratoses (AKs) of the face and scalp, for basal cell carcinoma and for Bowen's disease. However, due to its intriguing mechanism of action, many dermatologists have begun to look at the use of PDT in photorejuvenation, acne vulgaris and hidradenitis suppurativa. Moreover, clinicians have to learn how to maximize this kind of therapy to treat other dermatologic entities, and many anecdotic reports can already be found in the literature. This paper aims to briefly but critically review these reports to give the dermatologist a useful guide to what could be the future experiences in PDT and how to target their efforts in clinics and research.