容积剂量参数V20和V30在评估和预测同步放化疗治疗局部晚期非小细胞肺癌致放射性肺损伤中的应用

Application of V20 and V30 volume dose parameters in evaluating and forecasting radioactive lung injury caused by concurrent radiochemotherapy in treatment of locally advanced non-small cell lung cancer

目的：探讨剂量体积直方图（DVH）容积剂量（Vd）参数V20和V30（双肺接受20和30Gy剂量照射的肺体积占全肺总体积的百分比）与同步放化疗治疗局部晚期非小细胞肺癌（LANSCLC）所致的放射性肺损伤的关系,明确能否用V20和V30评价和预测同步放化疗放射性肺损伤发生率。方法：入选本研究的同步放化疗患者36例,均采用三维适形放疗（3D-CRT）,常规分割2Gy/次,5次/周,总剂量60-66Gy/30-33F。有锁骨上淋巴结转移者也在常规放疗时另设野,给予电子线局部补量至60-70Gy/7周。化疗方案为紫杉醇＋卡铂（Taxol＋Carboplatin）,Taxol 135 mg·m-2,第1天、第22天;Carboplatin药时曲线下面积（AUC）=6g·L-1·min-1,第1天、第22天化疗。将2级以上放射性肺损伤分级与V20和V30进行相关分析,并根据全肺V20平均值（25.32%）及V30平均值（18.17%）分别进行分组,包括V20≤25%、V20〉25%组和V30≤18%、V30〉18%组,比较各组患者2级以上放射性肺损伤发生率。结果：2级以上放射性肺损伤的分级与V20和V30均呈正相关关系（r=0.740,P〈0.05;r=0.705,P〈0.05）。V20≤25%和V20〉25%组2级以上放射性肺损伤的发生率分别为17.64%和52.63%,组间比较差异有统计学意义（P〈0.05）;V30≤18%和V30〉18%组2级以上放射性肺损伤的发生率分别为16.67%和55.56%,组间比较差异有统计学意义（P〈0.05）。结论：容积剂量参数V20和V30可用于评估和预测同步放化疗后放射性肺损伤的发生率,同步放化疗中V20〉25%及V30〉18%时放射性肺损伤的发生率明显增高,需要对治疗计划进行修改,甚至放弃所设计的治疗计划。

Objective To research the relationship between volume dose（Vd）parameters V20 and V30of dose volume histogram（DVH）and radioactive lung injury caused by concurrent radiochemotherapy in the treatment of locally advanced non-small cell lung cancer（LANSCLC）,and to clear whether V30 and V20could evaluate the probability of radioactive lung injury in chemoradiation. Methods 36 patients treated with concurrent radiochemotherapy were retrospectively analyzed.Radiotherapy Ways ：3D-CRT,the conventional fractionation was 2Gy/frack（F）,5times/week,the total dose in concurrent chemoradiotherapy group was 66-70Gy/30-33 F and the total dose in sequential chemoradiotherapy group was 60-70 Gy/30-35 F.Chemotherapy plan：Taxol135mg·m-2 at the 1st and 22 nd days,Carboplatin AUC=6g·L-1·min-1,at the 1st and 22 nd days.The correlation analysis between the grade of level 2or higher incidence of radioactive lung injury and DVH parameters（V30and V20）was performed.And according to the whole lung average V30（18.17%）and V20（25.32%）,the groups were set up：V30≤18%,V30〉18% and V20≤25%,V20〉25%,and the incidence of levels 2or higher radioactive lung injury in each group was compared.Results There has positive correlation between levels 2or higher lung injury classification and V20,V30（r=0.705,P〈0.05;r=0.740,P〈0.05）;the incidence of levels2 or higher lung injury was respectively 16.67% and 55.56%in V30 ≤ 18.00% group and V30〉18.00% group,and there was significant difference（P〈0.05）;the incidence of levels 2or higher lung injury was respectively17.64% and 52.63% in V20 ≤25% and V20〉25% groups,and there was significant difference（P〈0.05）.Conclusion V30 and V20can be used to evaluate and forecast the incidence of radioactive lung injury;when V30〉18% and V20〉25%,the incidence of radioactive lung injury is significantly increased,and the treatment plan needs to be modified and even the design of treatment plan is given up.