左侧乳腺癌保乳术后放疗采用深吸气屏气技术肺部剂量Meta分析

目的:通过Meta分析探究左侧乳腺癌保乳术后放疗使用深吸气屏气技术对左肺剂量的影响。方法:2020年11月01日前检索PubMed、EMBASE、Web of Science寻找符合纳入标准的期刊文章，评价指标为左肺V20及左肺Dmean，通过Stata 12.0对提取的研究数据行Meta分析。结果:纳入20篇文献，共663例患者，异质性分析结果I2 检验(I-squared=69.5%)及Q检验(P=0.000)提示纳入20项研究间异质性较大。亚组分析结果:40例及以上组I2检验（I-squared=0%）及Q检验(P=0.909)提示各研究间无异质性；40例以下组I2检验（I-squared=76.8%）及Q检验(P=0.000) 提示异质性显著，说明异质性来源可能为样本量过小。最终对40例及以上组7项研究进行效应量合并，左肺V20在DIBH与自由呼吸（FB）两组间差异具有统计学意义［SMD=-0.28,95%CI（-0.41，-0.15），Z=4.16,P=0.000］；左肺Dmean在DIBH与FB两组间差异具有统计学意义［SMD=-0.20,95%CI（-0.33，-0.07），Z=2.96,P=0.003］。Egger回归检验结果提示本研究不存在明显的发表偏倚V20（P=0.971>0.05）及Dmean（P=0.666>0.05）。结论:左侧乳腺癌保乳术后放疗使用DIBH技术可以降低肺部照射剂量，从而减少放射性肺炎的发生概率，具有一定的临床价值。

Meta-analysis of lung dose in breast-conserving postoperative radiotherapy of left breast cancer using deep inspiration breath-hold technique

Objective:To explore the effect of deep inspiration breath-hold(DIBH) technology on left lung dose in postoperative radiotherapy of left breast cancer by Meta-analysis.Methods:Search PubMed,EMBASE,Web of Science before November 1,2020 to find journal articles that meet the inclusion criteria.The evaluation indicators are left lung V20 and left lung Dmean,and use Stata 12.0(Stata Corp LP,USA) to analyze the extracted research data.Results:A total of 663 patients were included in 20 articles.The heterogeneity analysis results of I2 test(I-squared=69.5%) and Q test(P=0.000) indicated that the included 20 studies were highly heterogeneous.Subgroup analysis results:I2 test(I-squared=0%) and Q test(P=0.909) for 40 cases and above,indicating that there is no heterogeneity among the studies.I2 test for 40 cases or less(I-squared=76.8%) and Q test(P=0.000) suggest significant heterogeneity,indicating that the source of heterogeneity may be too small sample size.Finally,the effect size of 7 studies in 40 cases and above groups was combined,and the difference in left lung V20 between DIBH and free breathing was statistically significant ［SMD=-0.28,95%CI(-0.41,-0.15),Z=4.16,P=0.000］.The difference of left lung Dmean between DIBH and FB is statistically significant ［SMD=-0.20,95%CI(-0.33,-0.07),Z=2.96,P=0.003］ .Egger regression test results suggest that there is no significant publication bias in this study V20(P=0.971>0.05) and Dmean(P=0.666>0.05).Conclusion:The use of DIBH technology after breast-conserving radiotherapy for early breast cancer can reduce the radiation dose to the lungs,thereby reducing the incidence of radiation pneumonitis,and has certain clinical value.