Abstract: | Photoradiation therapy, in which hematoporphyrin derivative is activated by an argon-dye laser, was performed on 46 superficial bladder tumors in 9 patients. A fluorospectrophotometric study of biopsies from these tumors and normal mucosa revealed preferential hematoporphyrin derivative localization in malignant tissues. The tumor response was confirmed ultrasonographically in 36 stages Ta to Tl tumors. Treatment with 100 to 250 J./cm.2 obtained complete remission in 5 of 6 patients with tumors 1 cm. in size or less. For those with tumors up to 2 cm. in size the light intensity should be 300 mw./cm.2 for 5 to 10 minutes or more and the accumulated energy intensity of light dose should be 100 J./cm.2 or more. No patient with tumors more than 2 cm. in size had a complete remission. |