Photodynamic therapy.

Photodynamic therapy (PDT) is an experimental cancer treatment modality that selectively destroys cancer cells by an interaction between absorbed light and a retained photosensitizing agent. This review discusses the basic components of photodynamic activity and examines the clinical applications of photodynamic therapy in cancer treatment. Treatment of superficial and early-stage malignancies is encouraging. Technologic advancement and further elucidation of the fundamental basis of photodynamic action should permit treatment of more advanced malignancies.