Evaluation of the efficacy of photodynamic therapy on experimental hepatocellular carcinoma--using local injection of photosensitizer

• Published in: Nihon Gan Chiryo Gakkai shi Vol. 25; no. 4; p. 770
• Main Authors: Yamashita, Y, Moriyasu, F, Tamada, T, Kawasaki, T, Ono, S, Kimura, T, Kajimura, K, Someda, H, Hamato, N, Uchino, H
• Format: Journal Article
• Language: Japanese
• Published: Japan 20.04.1990
• Subjects: Animals; Carcinoma, Hepatocellular - drug therapy; Chlorophyll - administration & dosage; Chlorophyll - analogs & derivatives; Chlorophyll - therapeutic use; Liver Neoplasms - drug therapy; Mice; Photochemotherapy; Rabbits
• ISSN: 0021-4671

The effect on photodynamic therapy (PDT) of using pheophorbide-a as a photosensitizer and Nd: YAG laser (Q-switch) was evaluated. Two hundred micrograms (0.1 ml) of pheophorbide-a was injected into tumors that had been subcutaneously implanted into the backs of nude mice (BALB/c-nu). Interstitial Nd: YAG laser irradiation (Q-switch; mean power 0.5 W, duration 10 min.) was performed 72 hours after pheophorbide-a injection. Forty-eight hours after laser irradiation, the areas of tumor necrosis were measured; these were larger in the group with the injection of pheophorbide-a than in those without. The areas of tumor necrosis after Nd: YAG laser irradiation at a higher mean power (Q-switch; mean power 2 W, control temperature 43-43.5 degrees C, duration 10 min.) were also measured. Again, the areas were larger in the group injected with pheophorbide-a. These results show that the injection of pheophorbide-a and interstitial irradiation using Nd: YAG laser induce a photodynamic reaction, and that this combination is useful in the treatment of deep-seated tumors.