肺癌适形放疗后放射性肺损伤CT分级的危险因素研究

目的 探讨接受三维适形放疗(3DCRT)后影响严重放射性肺损伤CT分级的危险因素。方法 回顾性分析89例3DCRT的肺癌患者临床资料和随访CT影像资料,统计各临床因素及剂量体积参数。观察放疗结束6～12个月的CT影像资料并根据CT影像资料对放射性肺损伤进行评定分级。分析≥3级严重放射性肺损伤的危险因素。统计采用SPSS15.0软件。结果 89例患者放射性肺损伤CT分级情况:0级8例占9.0%,1级13例占14.6%,2级24例占27.0%,3级23例占25.8%,4级21例占23.6%。单因素分析显示同步化疗(CCT)、大体肿瘤体积(GTV)外放边界、患侧肺平均剂量、患侧肺的V₁₅～V₄₅差异有统计学意义。多因素Logistic回归分析显示:CCT、GTV外放边界和患侧肺V₂₀是影响严重放射性肺损伤CT分级的独立危险因素。结论 对接受3DCRT的肺癌患者,CCT、GTV外放边界和患侧肺V₂₀是影响严重放射性肺损伤CT分级的临床和剂量学危险因素。

Risk factors for computed tomography grade of radiation-induced lung injury in lung cancer treated with three-dimensional conformal radiotherapy

Objective To analyze the clinical and dosimetric risk factors for computed tomography(CT) grade of radiation-induced lung injury in lung cancer treated with three-dimensional conformal radiotherapy (3DCRT). Methods Eighty-nine lung cancer patients treated with 3DCRT were enrolled and CT scan images in more than 6 months were retrospectively analyzed. Clinical and dosimetric parameters were reviewed. Radiation-induced lung injuries were classified into 5 grades on CT images. Grade 3 or worse were considered clinically significant. Statistical software SPSS 15.0 was used to analyze the clinical and dosimetric risk factors that influenced the CT grade of radiation-induced lung injury. Results Eight of 89 patients (9.0%) developed grade 0 of radiation-induced lung injury, 13 developed grade 1(14.6%), 24 developed grade 2(27.0%), 23 developed grade 3(25.8%)and 21 developed grade 4(23.6%). Univariable analysis showed that concurrent chemotherapy(CCT), GTV margin, involved ipsilateral lung mean lung dose(IMLD), the percent of involved ipsilateral lung receiving over 15,20,25,30,35,40 and 45 Gy (V ₁₅, V ₂₀, V ₂₅, V ₃₀, V ₃₅, V ₄₀, V ₄₅) were significantly associated with over grade 3 of radiation-induced lung injury . On multivariate logistic regression analysis, CCT, GTV margin and V ₂₀ of ipsilateral lung emerged as statistically significant risk factors of over grade 3 radiation-induced lung injuries CT images. Conclusions CCT, GTV margin and V20 of ipsilateral lung might be clinical and dosimetric risk factors associated with the severe CT grade of radiation-induced lung injury for lung cancer treated with 3DCRT.