Laramore G E, Diener-West M, Griffin T W, Nelson J S, Griem M L, Thomas F J, Hendrickson F R, Griffin B R, Myrianthopoulos L C, Saxton J
Department of Radiation Oncology, University of Washington Hospital, Seattle 98195.
Int J Radiat Oncol Biol Phys. 1988 Jun;14(6):1093-102. doi: 10.1016/0360-3016(88)90384-7.
From September 1980 through January 1985, the Radiation Therapy Oncology Group (RTOG) conducted a randomized, dose-searching study testing the efficacy of a concomitant neutron boost along with whole brain photon irradiation in the treatment of malignant gliomas of the brain. Patients had to have biopsy-proven, supratentorial, anaplastic astrocytoma or glioblastoma multiforme (Nelson schema) to be eligible for the study. The whole brain photon irradiation was given at 1.5 Gy per treatment, 5 days-a-week to a total dose of 45 Gy. Two days-a-week the patients were to receive neutron boost irradiation to the tumor volume as determined on CT scans. The neutron irradiation was to be given prior to and within 3 hours of the photon irradiation on that day. The rationale for this particular treatment regime is discussed. A total of 190 evaluable patients were randomized among 6 different neutron dose levels: 3.6, 4.2, 4.8, 5.2, 5.6 and 6.0 Gyn gamma. There was no difference in overall survival among the 6 different dose levels, but for patients having less aggressive tumor histology (anaplastic astrocytoma), there was a suggestion that patients on the higher dose levels had poorer overall survival than patients on the lower dose levels and also did worse than historical photon controls. Important prognostic factors were identified using a Cox stepwise regression analysis. Tumor histology, Karnofsky performance status, and patient age were found to be related to survival while extent of surgery and neutron dose had no significant impact. Autopsies were performed on 35 patients and the results correlated with the actual neutron dose as determined by central-axis isodose calculations. At all dose levels there were some patients with both radiation damage to normal brain tissue and evidence of viable tumor. No evidence was found for a therapeutic window using this particular treatment regimen.
从1980年9月至1985年1月，放射治疗肿瘤学组（RTOG）开展了一项随机剂量探索性研究，以测试同步中子增敏联合全脑光子照射治疗脑恶性胶质瘤的疗效。患者必须经活检证实为幕上间变性星形细胞瘤或多形性胶质母细胞瘤（Nelson分型）才有资格参加该研究。全脑光子照射每次剂量为1.5 Gy，每周5次，总剂量为45 Gy。患者每周2次接受中子增敏照射，照射范围为CT扫描确定的肿瘤体积。中子照射应在当天光子照射之前及照射后3小时内进行。文中讨论了这种特殊治疗方案的理论依据。共有190例可评估患者被随机分配到6种不同的中子剂量水平：3.6、4.2、4.8、5.2、5.6和6.0 Gyn γ。6种不同剂量水平的总生存率无差异，但对于肿瘤组织学侵袭性较小（间变性星形细胞瘤）的患者，有迹象表明高剂量水平组患者的总生存率低于低剂量水平组患者，且比历史光子治疗对照组更差。使用Cox逐步回归分析确定了重要的预后因素。发现肿瘤组织学、卡诺夫斯基功能状态和患者年龄与生存率相关，而手术范围和中子剂量无显著影响。对35例患者进行了尸检，结果与通过中心轴等剂量计算确定的实际中子剂量相关。在所有剂量水平下，都有一些患者既有正常脑组织的放射性损伤又有存活肿瘤的证据。未发现使用这种特殊治疗方案存在治疗窗的证据。
