Ⅲ期非小细胞肺癌三维适形放疗所致放射性肺炎的影响因素

Influence Factors for Radiation Pneumonitis in Stage Ⅲ Non-small Cell Lung Cancer Patients Treated with Three-dimensional Conformal Radiotherapy

目的回顾性分析Ⅲ期非小细胞肺癌(NSCLC)三维适形放疗(3D-CRT)引起放射性肺炎(RP)发生的相关物理参数及临床影响因素。方法 2001年1月至2008年12月接受根治性3D-CRT的203例NSCLC临床资料,其中男163例、女40例;中位年龄63岁(30~83岁);21例有慢性阻塞性肺疾病(COPD)病史;ⅢA期79例、ⅢB期124例。70例单纯放疗、133例放化联合治疗,中位等效照射剂量6 200 c Gy(5 000~7 800 c Gy);RP评价采用RTOG标准,剂量体积直方图(DVH)评价物理参数与≥2级和≥3级RP的关系。统计分析采用SPSS13.0统计软件。结果 203例放疗后发生≥2级RP者32%(65/203),≥3级RP者20.7%(42/203)。Spearman相关和Logistic单因素分析显示,物理参数中肺平均剂量、双肺V5~V40,临床因素中COPD病史、分割方式(常规分割/大分割)、放疗剂量、GTV和GTV/肺体积均与≥2级和≥3级RP相关(P<0.05);而性别、年龄、吸烟、病变部位(中央型/周围型、肺上叶/肺中下叶)、化疗与否等均与≥2级和≥3级RP无明显关系(P>0.05)。Logistic多因素回归分析显示,肺V25是≥2级和≥3级RP的独立危险因素,ROC曲线显示肺V25分界值为29%;COPD是≥2级RP的独立危险因素。结论 DVH参数可用于预测和评价放射性肺炎,肺V25可能是最有效预测≥2级RP和≥3级RP的指标,合并COPD增加≥2级RP的发生率。

Objective To retrospectively analyze physical parameters and clinical factors for radiation pneumonitis(RP) in stage Ⅲ non-small cell lung cancer(NSCLC) patients treated with three-dimensional conformal radiotherapy(3D-CRT).Methods From January 2001 to December 2008,203 NSCLC patients were treated with radical 3D-CRT,163 males and 40 females; Median ages was 63-year-old(30～83); 21 patients were suffered from chronic obstructive pulmonary disease(COPD) medical history; 79 cases were in ⅢA stage and 124 cases were in ⅢB stage; 70 cases were treated with single radiotherapy and 133 cases with chemoradiotherapy,and median equivalent dose was 6 200 cGy (5 000-7 800 cGy).RP was evaluated with RTOG standard,and physical parameters of DVH was used to estimated RP grade≥2 and RP grade≥ 3.SPSS 13.0 software was used for statistic analysis.Results After 3DCRT,the rates of RP grade≥2 and grade ≥ 3 were 32％(65/203) and 20.7％(42/203).Spearman correlation and single factor Logistic analysis showed that the mean lung dose,V5-V40 of total lung,COPD history,fractional radiation style,radiotherapy dose,GTV and GTV/volume of total lung were correlated with RP grade≥2 and grade≥≥3 (P＜0.05); Logistic multivariate analysis revealed that V25 was the independent risk factor for RP grade ≥ 2 and grade ≥ 3.The optimal cutoff value for lung V25 was 29％ in the receiver-operating characteristic (ROC) curve.COPD was the independent risk factor for RP grade ≥2.Conclusion DVH parameters were associated with the occurrence of RP.V25 might be the most effectively independent risk factor for RP grade≥2 and grade ≥3.COPD was the independent risk factor for RP grade ≥ 2 in patients with non-small cell lung cancer.