Photodynamic therapy in dermatology

The combination of light and chemicals to treat skin diseases is widely pra cticed in dermatology. Within this broad use of light and drugs, in recent years the concept of photodynamic therapy (PDT) has emerged. PDT is a promi sing modality for the management of various tumors and nonmalignant disease s, based on the combination of a photosensitizer that is selectively locali zed in the target tissue and illumination of the lesion with visible light, resulting in photodamage and subsequent cell death. Moreover, the fluoresc ence of photosensitizing compounds is also utilized as a helpful diagnostic tool for the detection of neoplastic tissue. Intensive basic and clinical research culminated in the worldwide approval of PDT for bladder, esophagea l, and lung cancer. The expanding use of this relatively new therapeutic mo dality in dermatology at many centers around the world has revealed its eff icacy for the treatment of cutaneous precancer and cancer, as well as selec ted benign skin disorders. The following article summarizes the main princi ples of PDT considering the most recent developments and provides a compreh ensive synopsis of the present status of the use of PDT in dermatology.