A Study on Photoradiation Therapy of Malignant Glioma Using Argon Laser

在体外模型、大鼠C_6胶质瘤模型和临床病例中研究了514.5 nm氩激光光照射治疗（PRT）的效果。在体外实验中，研究了PRT对肿瘤细胞的损伤机制以及PRT对肿瘤细胞的选择性作用。从细胞内HpD摄取和PRT对活细胞的作用观察以及透射电镜观察结果表明，PRT后的初始损伤可能发生在细胞质上。虽然肿瘤细胞对PRT的敏感性高于其他功能细胞，但肿瘤细胞损伤对PRT的选择性不高。本研究也支持肿瘤血管损伤是肿瘤血管对PRT的特异性反应的假设，因为正常内皮细胞对PRT的敏感性低于肿瘤细胞。通过对大鼠C_6胶质瘤模型的研究发现，PRT对肿瘤的初始作用包括肿瘤细胞损伤和肿瘤血管损伤。在287焦耳/cm^2和15mg HpD / kg的剂量下，调至514.5 nm的氩激光产生的肿瘤破坏深度从3到5毫米不等。临床研究提示，PRT可引起肿瘤细胞坏死、血管充血、受照部位水肿改变，局部温度无明显升高。然而，由于本研究的患者数量太少，似乎很难评估PRT的效果并得出关于PRT疗效的结论。

We studied on the effect of photoradiation therapy (PRT) using the argon laser tuned to 514.5 nm in the in vitro model, the rat C_6 glioma model and clinical cases.In the in vitro study, mechanisms of cell damage by PRT and the selective effect of PRT on tumor cells were investigated. It is suggested that the initial damage after PRT may occur to the cytoplasm, from observations of intracellular uptake of HpD and the effect of PRT on living cells, and from the findings obtained by transmission electronmicroscope. Although tumor cells were more sensitive to PRT than other functional cells, Cell damage of tumor appeared not to be highly selective to PRT. This study also supports the hypothesis that vascular damage of tumors is attributable to a specific reaction of tumor vessels to PRT, since normal endothelial cells are less sensitive to PRT than tumor cells.From the study of the rat C_6 glioma model, it was concluded that the initial effects of PRT on tumors include both tumor cell damage and tumor vessel damage. Argon laser tuned to 514.5 nm at doses of 287 joules/cm^2 and 15 mg of HpD per kg produced tumor destruction ranging from 3 to 5mm in depth.The clinical study suggested that PRT may produce necrosis of tumor cells, vascular congestions, and edematous change in the irradiated areas without significant elevation of local temperature. It seems, however, difficult to evaluate the effect of PRT and to draw conclusions concerning the efficacy of PRT, because the number of patients in this study is too small.