Current status of photodynamic therapy for human cancer

Although clinical trials in photodynamic therapy (PDT) have been ongoing for over a decade, attempts to apply for approval of the therapy from boards of health for general use began only in 1989. The steps which are being taken to approve PDT for the treatment of endobronchial lung cancer, superficial bladder cancer and esophageal cancer are described. Technological innovations which have been suggested as increasing the ease of use of PDT as a therapeutic modality are briefly discussed.