The Effects of Photodynamic Therapy with Photogem and Laser with Power Density of 600 mW/cm2 on Lewis Lung Carcinoma Cells Tumor Graft in Mouse

ABSTRACT

PURPOSE: Photodynamic therapy was used to lung cancer. We have made a light microscpic study on the effects of photodynamic therapy to tumor graft in skin of mice, when the power density was 600 mW/cm2 with reducing time. MATERIALS AND METHODS: These studies had been performed on sixteen C57BL/6 mice that Lewis lung carcinoma cells had been implanted. All mice were divided into four groups. One of four groups received Photogem 3 mg/kg intravenously 24 hours prior to exposure of tumor to 180 J/cm2 laser light vertically at a wavelength 635etam with a higher power density of 600 mW/cm2 than that of 400 mW/cm2 clinically. One of these group received only Photogem. The others not received Photogem and one of these irradiated with laser. The light source was the wavelength of 635 etam Diode Laser (Laxcell 2004, Bio- Optics. co. Korea) After photodynamic therapy was finished, staining and analysing of tumors were used to determine the natures and extents of injury. RESULTS: Grossly response was not observed. Histologically, there were loss of endothelium from small vessel at tumor and muscle with thrombus formation. There were focal necrosis with infiltration of inflammatory cells at tumor and adjacent tissues that irradiated with laser, regardless of administration of Photogem. CONCLUSION: Photodynamic therapy using Photogem and LASER with power density of 600 mW/cm2 destroy not only tumors incompletely but also adjacent normal tissue.