A study of photodynamic therapy for interstitial laser irradiation methods using Microselectron ® tube

The purpose of this study is to evaluate after-loading interstitial photodynamic therapy using Microselectron ® tube for advanced cancer. Materials and Methods: VX2 carcinoma was transplanted into the dorsal surface of Japanese white rabbits. When the cancer grows up to the size of 32×20×20mm, a dose of 5mg/kg of the photosensitizer, Hematoporphyrin derivative made by the QUENTRON OPTICS company was administered intravenously. Microselectron ® tube was implanted into the tumor 24 hours after the administration in which the optic fiber was inserted and rotated. The irradiation conditions were 40.8mm/min, 17.5R.P.M., a pulse repetition frequency of 80Hz and 5mJ/pulse. The total light doses along a tube were 150J/cm. Result: No significant change of tumor temperature by laser beam was observed. The tumor around the tube was destroyed up to the extent of 28mm in diameter. We suggest that after-loading interstitial photodynamic therapy using Microselectron ® tube is applicable for treatment of advanced cancer.