多参数磁共振成像VI-RADS评分对膀胱癌肌层浸润诊断价值的初步研究

Diagnostic value of multiparametric MRI using vesical imaging reporting and data system in detecting muscle-invasiveness of bladder cancer

目的:探讨多参数磁共振成像(mp-MRI)膀胱影像报告和数据系统(VI-RADS)的评分一致性及其在膀胱癌肌层浸润中的诊断价值。方法:回顾性分析经手术病理证实的99例(共109个癌灶)膀胱癌患者的资料。根据肿瘤是否侵犯固有肌层分为非肌层浸润性膀胱癌(NMIBC,≤T1期)和肌层浸润性膀胱癌(MIBC,≥T2期)两组。由两位阅片者独立盲法对病灶mp-MRI图像进行VI-RADS评分。采用Kappa检验分析两位阅片者VI-RADS评分的一致性。绘制受试者工作特征曲线(ROC)分析VIRADS评分诊断膀胱癌肌层浸润的效能。结果:两位阅片者VI-RADS评分一致性良好(Kappa值=0.721,P<0.001)。根据ROC曲线分析,以VI-RADS≥4分为阈值,两位阅片者的诊断曲线下面积(AUC)分别为0.912和0.925,敏感性为76.2%和71.4%,特异性为95.5%和95.5%,阳性预测值为80.0%和79.0%,阴性预测值为94.4%和93.3%。结论:VI-RADS评分具有良好的一致性和稳定性。mp-MRI VI-RADS评分对膀胱癌肌层浸润的诊断具有重要的价值,有较高的特异性和阴性预测值。

Objective: To investigate interobserver agreement and diagnosis value of multiparametric MRI(mp-MRI) using vesical imaging-reporting and data system(VI-RADS) in detecting muscle-invasiveness of bladder cancer. Methods: Retrospective analysis of 99 patients(109 tumors in total) with pathologically confirmed bladder cancer was made in this study. The tumors was classified as non-muscle invasive bladder cancer(NMIBC) with stage T1 or lower and muscle invasive bladder cancer(MIBC) with stage T2 or higher. The mp-MRI images of tumors were scored by two radiologists independently with blind method by using VI-RADS. Interobserver agreement was evaluated by using Kappa test. Receivers operating characteristic(ROC) curves were used to describe the diagnostic efficiency of two radiologists. Results: Interobserver agreement of VI-RADS was good(Kappa value=0.721, P<0.001). According to ROC analysis, VI-RADS score 4 was found to be the best cut-off levels for discriminating NMIBC from MIBC by two radiologists, with the AUC of 0.912 and 0.925, the sensitivity of 76.2% and71.4%, the specificity of 95.5% and 95.5%, the positive predictive value of 80.0% and 79.0%, the negative predictive value of 94.4% and 93.3%, respectively. Conclusion: The VI-RADS shows good consistency and stability for evaluation bladder cancer. Futhermore, VI-RADS demonstrates a good accuracy in the detection of muscle-invasiveness of bladder cancer, and provides a high specificity and negative predictive value.