肺癌插植放疗中插植针排列规则对肺受量影响研究

目的 分析肺部肿瘤的近距离组织间插植放疗插植针的排列规则对肺受照剂量影响。方法 针对15例近距离组织间插植放疗肺癌患者病例,设计不受肋骨限制的插植针规则排列的放疗计划,命名为虚拟计划并与原实际计划进行比较。分别统计当两种计划方案的处方剂量为 10、30、60、120 Gy时肺V5、V20、V30、MLD。采用Wilcoxon符号秩检验。结果 虚拟计划方案的肺V5、V20、V30、MLD均小于实际计划方案,差异均有统计学意义(P<0.05)。结论 插植针的不规则排列限制了近距离组织间插植放疗在肺受量上进一步降低;所以在插植手术中应尽可能使得插植针规则排列。

Effect of needle arrangement on the lung dose in interstitial brachytherapy for lung cancer

Objective To analyze the effect of needle arrangement on the lung dose in interstitial brachytherapy for lung cancer. Methods For 15 patients undergoing interstitial brachytherapy for lung cancer, a virtual radiotherapy plan in which needle arrangement was not restricted by the ribs was designed and compared with the original plan. For the two plans, V5, V20, V30, and mean lung dose (MLD) of the whole lung were determined when the prescribed doses were 10, 30, 60, and 120 Gy, respectively. The data were analyzed by Wilcoxon signed-rank test. Results The lung V5, V20, V30, and MLD were significantly smaller in the virtual plan than in the actual plan (all P<0.05). Conclusions Irregular needle arrangement prevents a further reduction in the lung dose in interstitial brachytherapy for lung cancer. In the implantation surgery, therefore, the needles should be arranged as regularly as possible.