铱^(192)核素行脑胶质瘤间质内放疗的动物实验与临床初步应用

The experimental and clinical preliminary studies of interstitial brachytherapy using Iridium192 on brain glioblastoma

目的：采用动物实验用立体定向技术瘤内置管作间质内放疗的生物学效应研究及临床初步应用分析。方法：动物实验用Ｇ４２２皮下荷瘤鼠模型及Ｃ６脑胶质瘤脑荷瘤鼠进行，每种分２．５Ｇｙ、１０Ｇｙ照射组及对照三组，观察皮下荷瘤鼠经间质内照射后的肿瘤生长抑制及脑荷瘤鼠经内照射后的鼠生长期延长情况及病理学观察。实验结果表明用铱１９２后装瘤内置管行间质内照射可引起肿瘤生长明显受到抑制，脑荷瘤鼠照射后生存期显著延长。临床应用：在此基础上我们用铱１９２后装机瘤内置管对５６例脑深部胶质瘤进行了铱１９２核素瘤间质内照射，肿瘤位于大脑半球深部２５例；基底节区１３例；三脑室后部１１例；脑室内４例；小脑内３例。３０例为原发胶质瘤，２６例为术后复发胶质瘤。行单管单点照射３９例；双管１５例；三管治疗２例；照射剂量３５～６５Ｇｙ，平均５６．５Ｇｙ。一般住院１５～２０天，无手术严重并发症，无死亡。１、２、３年存活率分别为９２．８％、８３．９％和７１．４％。结论：经实验与临床初步应用证明。

Objective: To evaluate the radiobiological effects on rat models with glioblastoma tumors models and the preliminary clinical results of interstitial brachytherapy undergoing temporary Iridium192 implant boost. Methods: G422 is the first domestic glioblastoma cell line for mouse. Hypodermicbearing tumor model is utilized for tumor inhabition. C6 glioma cells are transplanted into rat by stereotactic technique. This model is utilized in survival time test. On the basis of animal experiment, the stereotactic brachytherapy with iridium192 were performed on 56 patients with deepsited gliomas. The pathological diagnosis were comfirmed by stereotactic biopsy in 30 cases and by operation in 26 cases. The maximum dosage ranged from 35 to 65 Gy, with an average of 565Gy. Results: After therapy at 14th day the mean tumor volume are significant difference between control group and radiated groups, and also significant difference between 25Gy group and 10Gy group. KaplanMeier survival analysis shown that the survival time of radiated group is longer than control group, and the 25Gy group is the longest. Clinically, there were no serious complication and death, and a good early results were got. Followup study showed that the survival rates at 1, 2 and 3 year after brachytherapy were 928%, 839% and 714% respectively. Conclusions: Adjunctive treatment of glioblastoma with discrete high doses of radiation therapy delivered by iridium192 brachytherapy allows further control of the brain tumors.