Abstract
Photodynamic therapy (PDT) is an experimental cancer treatment modality that selectively destroys cancer cells by an interaction between absorbed light and a retained photosensitizer. A wide variety of malignancies have been treated by this method and according to the worldwide literature, over 3000 patients have been treated thus far with photodynamic therapy. The applications of PDT via endoscopy have been investigated in our laboratory since 1978, and the therapeutic effectiveness of this technique was demonstrated in our canine tumor model. PDT has been applied clinically since 1980 at Tokyo Medical College in a total of 390 patients including 240 patients with lung cancer, and 24 with esophageal cancer. Results were extremelly good especially for endoscopically early stage lung cancer. Complete remission, which means no evidence of tumor endoscopically, cytologically and histologically, was obtained in 79 lesions out of 95 lesions (83.2 %) of early stage lung cancer
