非小细胞肺癌三维适形放疗放射性肺损伤剂量学因素分析

目的 观察非小细胞肺癌三维适形放疗患者急性放射性肺炎的发生情况，并分析其与各剂量学因素的关系。方法 收集2010年6月—2010年12月间首程行三维适形放疗的非小细胞肺癌患者68例。从治疗计划系统的剂量体积直方图中获取以下剂量学参数：处方剂量、平均肺剂量(MLD)、正常肺体积剂量（V5~V50间隔5 Gy）等，分别采用单因素及多因素分析各个剂量学参数与放射性肺炎之间的关系，并采用受试者工作特征曲线寻找预测界值。结果 V5是放射性肺炎发生的独立预后因素（χ2=5.15，P=0.023）。患者肺脏的V5超过57%时放射性肺炎的发生率可能会增加。结论 临床医师在审核治疗计划时，除了要考虑V20、V30、MLD等常用参数外，还应关注V5的大小。

Dosimetric Factors Analysis of Radiation-induced Lung Damage in Non-small Cell Lung Cancer Patients Treated with Three-dimentional Conformal Radiotherapy

Objective To observe the incidence of acute radiation pneumonitis in non-small cell lungcancer(NSCLC) patients treated with three-dimentional conformal radiotherapy (3DCRT), and to investigatethe correlation between dosimetric parameters and radiation pneumonitis. Methods From June 2010 toDecember 2010, 68 NSCLC patients treated with 3DCRT were retrospectively reviewed. The followingdosimetric parameters were calculated from dose-volume histogram (DVH) system: total dose, mean lungdose(MLD), V5, V10, V15, V20, V25, V30, V35, V40, V45 and V50. Univariate and multivariate analyseswere performed to determine the correlation between those factors and radiation pneumonitis. Results V5was the independent factor significantly associated with radiation-induced lung damage(χ2=5.15, P=0.023).The incidence of radiation pneumonitis would be increased if V5 was more than 57%. Conclusion Exceptcommon parameters, such as V20, V30, MLD, etc., V5 should also be considered in assessing radical 3DCRTplan.