Photosensitizers for Photodynamic Therapy: Photochemistry in the Service of Oncology.

The combined use of a photosensitizing agent, light and dioxygen for the treatment of diseases has become known as photodynamic therapy (PDT) and was first discovered more than one hundred years ago. Over the years, PDT has proven its potential for the treatment of malignant and non-malignant lesions in addition to classical cancer therapy in numerous clinical studies, but application as a routine method is still limited. In this review, the development of modern PDT since the beginning of the twentieth century is briefly portrayed.