MR扩散加权成像中应用ADC值鉴别良、恶性淋巴结的Meta分析

Differentiation of benign and malignant lymph nodes with ADC value on diffusion MR： a Meta- analysis

目的 采用循证医学Meta分析的方法,探讨DWI-ADC值鉴别良、恶性淋巴结的可行性.方法 检索1998年至今公开发表的良、恶性淋巴结DWI-ADC值差别研究的中、英文文献,对符合纳入条件的原始研究进行质量评价,提取特征信息.对提取的信息进行异质性检验.根据异质性检验结果选择相应的效应量合并模型.合并效应量为ADC值差别的加权平均差和诊断性试验的敏感性、特异性、阳性似然比、阴性似然比、诊断比值比,计算验前、验后概率,以定性和定量的方法研究良、恶性淋巴结DWI-ADC值差别及临床应用价值.结果 符合纳入标准的文献共15篇,研究对象735例,淋巴结1963个.Meta回归分析、亚组分析和敏感性分析显示,2项良性淋巴结来自健康对照和1项采用化学位移选择法压脂技术的研究,对汇总结果影响较大,合并效应量时予以剔除.恶性淋巴结与良性淋巴结的ADC值的加权均数差值为-0.355×10-3mm2/s[95％可信区间（CI） -0.423×10-3～-0.288×10-3mm2/s].虽然各研究鉴别良、恶性淋巴结采用的ADC界值不同,但鉴别良、恶性淋巴结的诊断指标稳定,汇总敏感性、特异性、阳性似然比、阴性似然比、诊断比值比和汇总受试者工作特征曲线下面积分别为：0.87（95％ CI：0.79～0.92）、0.87 （95％ CI：0.82～0.90）、6.5 （95％ CI：4.7～9.2）、0.15（95％ CI：0.09～0.25）、43 （95％ CI：21～87）、0.93 （95％ CI：0.90～0.95）,ADC提示良性的淋巴结验后恶性率为6％,ADC提示恶性的淋巴结验后恶性率为72％.结论 恶性淋巴结ADC值低于良性淋巴结,是一种准确性较高的鉴别良、恶性淋巴结的无创性检查方法.

Objective To summarize the diagnostic efficacy of ADC value for differentiation of benign and malignant lymph nodes on diffusion MRI with Meta-analysis. Methods Published papers on differentiation of benign and malignant lymph nodes with ADC value were searched and reviewed.Quality evaluation was performed for the eligible papers before data extraction.Test for heterogeneity was performed first,then appropriate model was selected to calculate the weighted mean difference,sensitivity,specificity,positive likelihood ratio,negative likelihood ratio,diagnostic odds ratio,pretest and posttest probability.The potential of ADC value for differentiation of benign and malignant lymph nodes was assessed qualitatively and quantitatively.Results Fifteen papers including 735 cases and 1963 lymph nodes were selected.According to Meta-regression analysis,subgroup analysis and robust analysis,two studies with benign lymph nodes in patients with benign lesion and one study using chemical shift saturation technique were excluded because of their impact on the robustness of the pooled results. The weighted mean difference （WMD） between malignant and benign lymph nodes was -0.355 × 10-3mm2/s[95% confidence interval （CI）：-0.423 ×10-3- -0.288 × 10-3 mm2/s].Although the cutoff of ADC value for differentiation in each study was different,the diagnostic efficacy was stable,the pooled sensitivity,specificity,positive likelihood ratio,negative likelihood ratio,diagnostic odds ratio and area under summarized receiver operator＇s curve were 0.87 （95% CI：0.79-0.92）,0.87 （95% CI：0.82-0.90）,6.5 （95% CI：4.7-9.2）,0.15 （95% CI：0.09-0.25 ）,43 （ 95% CI：21-87 ）,0.93 （ 95 % CI：0.90-0.95 ）.The posttest malignancy probability of benign lymph node indicated by ADC was 6%,while that of malignant lymph node was 72%.Conclusion The ADC value can be used to differentiate benign and malignant lymph nodes with good sensitivity and specificity noninvasively.