表观弥散系数值用于预测肝外胆管癌淋巴血管侵犯

Apparent diffusion coefficient for predicting lymphovascular invasion from extrahepatic cholangiocarcinoma

目的分析表观弥散系数(ADC)用于评估肝外胆管癌(ECCA)淋巴血管侵犯(LVI)的价值。方法回顾性分析经术后病理证实的85例单发ECCA患者,术前均接受常规MRI及弥散加权成像(DWI),根据病理结果将其分为LVI阳性组与LVI阴性组;比较组间ADC值差异,以受试者工作特征(ROC)曲线评估ADC值对LVI的诊断效能。结果85例ECCA中,22例存在LVI(LVI阳性组),63例无LVI(LVI阴性组)。LVI阳性组ADC值为1.17×10^(-3)(1.08×10^(-3),1.31×10^(-3))mm^(2)/s,LVI阴性组为1.32×10^(-3)(1.25×10^(-3),1.45×10^(-3))mm^(2)/s,组间差异有统计学意义(P<0.05)。ADC值诊断LVI阳性的ROC曲线下面积(AUC)为0.80[95%CI(0.69,0.91),P<0.05],判断LVI阳性的ADC值阈值为1.18×10^(-3)mm^(2)/s,其诊断敏感度、特异度、阳性预测值、阴性预测值及准确率分别为63.64%(14/22)、90.48%(57/63)、70.00%(14/20)、87.69%(57/65)及83.53%(71/85)。结论基于ADC值可判断ECCA患者是否存在LVI。

Objective To explore the value of apparent diffusion coefficient(ADC)for assessment of lymphovascular invasion(LVI)from extrahepatic cholangiocarcinoma(ECCA).Methods Totally 85 patients with single ECCA lesion confirmed by postoperative pathology were retrospectively analyzed.All patients underwent conventional MRI and diffusion weighted imaging(DWI)before operation.The patients were divided into LVI positive group and LVI negative group according to pathological results.ADC values were compared between groups,and the diagnostic efficacy of ADC values for LVI was evaluated with receiver operating characteristic(ROC)curve.Results Among 85 ECCA patients,there were 22 cases with LVI(LVI positive group)and 63 cases without LVI(LVI negative group).ADC value of LVI negative group was 1.32×10^(-3)(1.25×10^(-3),1.45×10^(-3))mm^(2)/s,of LVI positive group was 1.17×10^(-3)(1.08×10^(-3),1.31×10^(-3))mm^(2)/s,and there were statistically difference of ADC values between groups(P<0.05).The area under the curve(AUC)of ADC value for diagnosing positive LVI was 0.80(95%CI[0.69,0.91],P<0.05).Taken 1.18×10^(-3)mm^(2)/s as the threshold of ADC value for predicting positive LVI,the sensitivity,specificity,positive predictive value,negative predictive value and accuracy was 63.64%(14/22),90.48%(57/63),70.00%(14/20),87.69%(57/65)and 83.53%(71/85),respectively.Conclusion ADC value could be used assess LVI in ECCA patients.