256例局部晚期NSCLC调强放疗后放射性肺损伤预测因素分析

目的 探讨局部晚期NSCLC受累野IMRT后放射性肺损伤发生率及寻找预测因素。方法 2007—2011年间在我院治疗的256例未手术、Ⅲ期NSCLC患者。放疗采用受累野IMRT。放疗剂量50~70 Gy (中位值60 Gy),分割剂量2 Gy/次。109例(42.6%)接受同期化疗。采用NCI的CTCAE 3.0标准评估级别。以放疗结束后6个月内发生≥2级放射性肺损伤作为终点事件。采用Logistic回归模型对预测因素进行分析。结果 所有患者中男215例(84%)、女41例(16%)。诊断时平均年龄59.2岁。43例(16.7%)发生≥2级放射性肺损伤。出现放射性肺损伤时间距放疗开始时间为20~169 d (中位数64 d)。单因素分析显示吸烟、肿瘤位置、双肺平均剂量、双肺V₅—V₂₀与≥2级放射性肺损伤发生可疑相关(P=0.108、0.106、0.030、0.049),多因素分析结果显示双肺平均剂量和双肺V₅—V₂₀与≥2级放射性肺损伤发生密切相关(P=0.048)。结论 局部晚期NSCLC受累野IMRT后双肺平均剂量和DVH中低剂量区体积可以初步预测症状性放射性肺损伤发生。

Predictive factors for radiation-induced lung injury in locally advanced non-small cell lung cancer after intensity-modulated radiotherapy

Objective To investigate the incidence of radiation-induced lung injury (RILI) in patients with locally advanced non-small cell lung cancer (LA-NSCLC) after involved-field intensity-modulated radiotherapy (IMRT) and concurrent chemotherapy, and to figure out the predictive factors for RILI. Methods Two hundred and fifty-six patients with stage Ⅲ NSCLC who were treated without surgery in our hospital from January 2007 to December 2011 were enrolled as subjects. All patients received involved-field IMRT with a median dose of 60 Gy (50-70 Gy) in 30 fractions. In all patients, 109 patients (42.6%) received concurrent chemotherapy. The National Cancer Institute Common Terminology Criteria for Adverse Events Version 3.0 was used to evaluate the RILI grade. The incidence of grade ≥2 RILI (symptomatic RILI, SRILI) within 6 months after radiotherapy served as the end point. The predictive factors for RILI were analyzed using logistic regression model. Results In all patients, 215(84%) were male, and 41(16%) were female. The mean age at diagnosis was 59.2 years. Forty-three (16.7%) patients had grade ≥2 RILI. The mean duration between the incidence of RILI and the beginning of radiotherapy was 64 days (20-169 days). Univariate analysis showed that smoking, peripheral or central tumor location, mean lung dose (MLD) for both lungs, and V₅-V₂₀ for both lungs were suspected to be associated with the development of SRILI (P=0.108,0.106,0.030,0.049). Multivariate analysis showed the MLD and V₅-V₂₀ for both lungs were independent predictive factors for SRILI P=(0.048). Conclusions For patients with LA-NSCLC treated with involved-field IMRT, the MLD and the volume of low-dose region in dose volume histogram for both lungs are significantly correlated with the incidence of SRILI.