Abstract
Photodynamic therapy (PDT) is one of modes of treatment for malignant tumors. In PDT, Argon-dye laser (ADL) irradiation following administration of hematoporphyin derivatives (HpD) is generally used. However, the poor tissue penetration and activation of photosensitisers of the ADL, are still problems with PDT. The Pulse-wave gold vapor laser (GVL) is considered to have better tissue penetration than that of the ADL, so we compared the efficacy of GVL and ADL., in PDT, by means of nude mice transplanted human gastric cancer.
Tumor size reduction and complete remission was obtained in the mice given GVL irradiation at 280mW/cm2 for 3 minutes with HpD (10mg/kg). The similar responce was obtained in the mice treated with the GVL at 280mW/cm2 for 10 minutes with or without HpD. On the other hand no effect of PDT was obtained in the mice given ADL irradiation at 280mW/cm2 for 10 minutes even with HpD. In the GVL group, the intra-tumor temperature was increased significantly.
It was concluded that GVL was superior to the ADL for PDT,because it had better tissue penetration, large power output, and an added hyperthermic effect.
