bp-MRI与mp-MRI对肌层浸润性膀胱癌诊断效能的对比研究

The comparison of diagnostic accuracy between biparametric magnetic resonance imaging and multiparametric magnetic resonance imaging in muscle-invasive bladder cancer

目的比较双参数磁共振成像(bp-MRI)与多参数磁共振成像(mp-MRI)对肌层浸润性膀胱癌(MIBC)的诊断效能。方法回顾性分析2020年7月至2022年6月于南京医科大学第一附属医院行经尿道膀胱肿瘤电切术或根治性膀胱切除术的195例膀胱癌患者的临床资料。男160例,女35例;中位年龄68(61,76)岁。所有患者术前6周内均行mp-MRI检查。将同一患者的图像分为两组:一组仅包含轴位、冠状位、矢状位T2加权成像(T2WI)和轴位扩散加权成像(DWI)/表观扩散系数序列,为bp-MRI组;另一组再额外包含轴位动态对比增强序列,为mp-MRI组。两组图像均由两名影像科医生分别进行独立判读赋分,并根据相应判读标准与最终病理结果进行比较。mp-MRI组的最终判读结果参考膀胱影像报告和数据系统(VI-RADS)指南,bp-MRI组的最终判读结果采用两种标准:当T2WI3分且DWI2分时,如VI-RADS被赋值为2分,则为bp-MRI(标准A);如VI-RADS被赋值为3分,则为bp-MRI(标准B)。对每种诊断方法分别以VI-RADS≥3分和VI-RADS≥4分作为诊断MIBC的截断值。对每种诊断MIBC的方法分别绘制受试者工作特性曲线,计算各自的曲线下面积(AUC),并进行比较分析。结果195例术后病理显示NMIBC135例(69.2%),MIBC60例(30.8%)。当以VI-RADS≥3分作为诊断MIBC的截断值时,bp-MRI(标准A)、bp-MRI(标准B)和mp-MRI诊断MIBC的敏感性相同,均为88.3%(53/60);bp-MRI(标准A)、bp-MRI(标准B)和mp-MRI的特异性分别为88.9%(120/135)、73.3%(99/13)和86.7%(117/135)。当以VI-RADS≥4分作为诊断MIBC的截断值时,bp-MRI(标准A)与bp-MRI(标准B)诊断效能完全相同;bp-MRI和mp-MRI的敏感性分别为70.0%(42/60)和75.0%(45/60),特异性均为95.6%(129/135)。bp-MRI(标准A)bp-MRI(标准B)和mp-MRI诊断MIBC的AUC分别为0.927(95%CI0.881~0.959)、0.904(95%CI 0.853~0.941)和0.927(95%CI 0.881~0.959),bp-MRI(标准A)和mp-MRI的AUC均显著大于bp-MRI(标准B)(P<0.001)bp-MRI(标准A)与mp-MRI的AUC差异无统计学意义(P=0.939)。结论在bp-MRI中,T2WI3分且DWI2分被VI-RADS赋值为2分时,在诊断MIBC方面与mp-MRI有相同的诊断效能。T2WI3分且DWI2分时,VI-RADS赋值为3分较赋值为2分诊断MIBC的效能可能更低.

Objective To compare the diagnostic accuracy between multiparametric magnetic resonance imaging(mp-MRI)and biparametric magnetic resonance imaging(bp-MRI)in muscle-invasive bladder cancer(MIBC).Methods The clinical data of 195 patients with bladder cancer at the First Affliated Hospital of Nanjing Medical University from July 2020 to June 2022,were retrospectively reviewed.There were 160 males and 35 females,with the median age of 68(61,76)years old.Mp-MRI was performed on each patient within 6 weeks before transurethral resection of bladder tumor or radical cystectomy.Each patients'images were divided into two sets.Set 1(bp-MRI)included the axial,sagttal,coronal T2-weighted images(T2WI),and axial diffusion-weighted images(DWI)or apparent diffusion coefficient maps.Set 2(mp-MRI)included Set 1 images in addition to dynamic contrast-enhanced images.All images were independently reviewed and evaluated by two radiologists.Mp-MRI was evaluated according to the Vesical Imaging-Reporting and Data System(VI-RADS)guideline,and bp-MRI was evaluated according to two types of criteria.Bp-MRI(Criterion A):VI-RADS scoring is determined 2 when T2WI 3-point with DWI 2-point.Bp-MRI(Criterion B):VI-RADS scoring is determined 3 when T2WI 3-point with DWI 2-point.VI-RADS scoring≥3 or≥4 was used as the cut-off value to predict MIBC.The sensitivity,specificity,positive predictive value,and negative predictive value of mp-MRI,bp-MRI(Criterion A),and bp-MRI(Criterion B)were calculated,as well as receiver operating characteristic curves and the areas under the curve(AUC).Results Of 195 patients,135 patients(69.2%)were pathologically confirmed as NMIBC and 60 patients(30.8%)were MIBC.When the VI-RADS cut-ff value was≥3,the sensitivity of mp-MRI,bp-MRI(Criterion A),and bp-MRI(Criterion B)were identical,all at 88.3%(53/60).The specificity of bp-MRI(Criterion A),bp-MRI(Criterion B),and mp-MRI were 88.9%(120/135),73.3%(99/13),and 86.7%(117/135),respectively.When the VI-RADS cut-off value was≥4,both bp-MRI(Criterion A)and bp-MRI(Criterion B)were classified as the same criterion.The sensitivity of bp-MRI and mp-MRI were 70.0%(42/60)and 75.0%(45/60),respectively.The specificity of bp-MRI and mp-MRI were identical,at 95.6%(129/135).The AUC for bp-MRI(Criterion A),bp-MRI(Criterion B),and mp-MRI were 0.927(95%CI 0.881-0.959),0.904(95%CI 0.853-0.941),and 0.927(95%CI 0.881-0.959),respectively.The AUC for bp-MRI(Criterion A)and mp-MRI were significantly higher than that of bp-MRI(Criterion B)(P<O.001).There was no significant difference in AUC between bp-MRI(Criterion A)and mp-MRI(P=0.939).Conclusions Bp-MRI(Criterion A),VI-RADS scoring is determined 2 when T2WI 3-point with DWI 2-point,shows comparable diagnostic accuracy in predicting MIBC with mp-MRI.Compared to bp-MRI(Criterion B),the corresponding situation when VI-RADS scoring is determined 3,bp-MRI(Criterion A)may have better diagnostic accuracy than bp-MRI(Criterion B)in predicting MIBC.