Application Of Multi-parametric Magnetic Resonance Imaging In Staging Of Bladder Cancer

ObjectiveBladder cancer is the most common malignancy in the urinary system.The clinical stage of bladder cancer is mainly non-muscle invasive bladder cancer(NMIBC),and muscle invasive bladder cancer(MIBC).In the clinic,the identification of NMIBC and MIBC is very meaningful for the selection of treatment procedures and protocols.The former,NMIBC,mainly uses transurethral bladder tumor resection(TURBT),and postoperative bladder perfusion,while the latter MIBC mostly uses radical cystectomy combined with other ancillary treatments.Multi-parametric magnetic resonance imaging(mpMRI)has great advantages in clinical diagnosis,stage classification and clinical efficacy monitoring of bladder cancer before surgery,which can effectively reduce the error rate of staging and is expected to become a stage of bladder cancer,regular inspection of grades.Based on data from previous mpMRI applications,Valeria Panebianco et al.proposed the VI-RADS scoring system in 2018,a multi-parametric magnetic resonance imaging scoring system for bladder cancer,which is used to score MRI in bladder cancer staging in order to form a systemic scoring guidelines,but they still lack sufficient sample size to support this study;this study uses the VIRADS scoring system to further explore multi-parametric magnetic resonance imaging(mpMRI)for muscle invasive bladder cancer(MIBC)and non-muscle invasive bladder cancer(NMIBC)Identification ability.MethodA total of 113 cases were collected from the Second Hospital of Tianjin Medical University from September 2017 to November 2018.After screening,65 cases were finally included in the study.In these cases,multi-parametric nuclear magnetic resonance imaging was examined.Two radiologists with urogenital experience independently analyzed the images independently.Three groups of images(T2WI,T2 WI plus TWI and DWI plus DCE)were analyzed for each patient,and the VIRSDA scoring system was used to stage the bladder cancer without understanding the operation or histology.The accuracy was determined by histopathology as a reference method.Statistical data for each muscle set to detect muscle insults including sensitivity,specificity,positive predictive value(PPV),negative predictive value(NPV),and accuracy were generated to generate a receiver operating characteristic(ROC)curve.The ROC curve was used to calculate the area under the curve,and then the T2 WI,T2WI plus DWI,T2 WI plus DWI plus DCE were used to diagnose the myometrial invasion of bladder cancer.ResultClear multi-parametric MRI is used in this study.There were 20 cases of non-muscle invasive tumors and 45 cases of muscle invasive tumors.The two physicians used T2 WI,T2WI plus DWI and T2 WI plus DWI plus DCE and VIRADS scoring system to determine whether there was muscle infiltration and pathology.Comparison.The consistency of muscle infiltration between the two radiologists was very good(Kappa value of T2 W was 0.904,T2 WI plus DWI was 0.924,T2 WI plus DWI plus DCE was 0.908).The sensitivity,specificity,and accuracy of the diagnosis of myometrial invasion by T2 WI were 77.5%,72.0%,and 75.0%,respectively,and the AUC was 0.748.The sensitivity,specificity,and accuracy of muscle infiltration were determined by T2 WI plus DWI.85.0%,80.0%,83.1%,AUC was 0.825;T2WI plus DWI plus DCE to determine the sensitivity,specificity,accuracy of myometrial invasion 95.0%,88.0%,92.3%,AUC was 0.915;The accuracy P value was 0.033,which was considered statistically significant.The area under the curve(AUC)of the Z test was 0.038,which was considered statistically significant.The sensitivity,specificity,and accuracy of the diagnosis of myometrial invasion by T2 WI were 75.0%,72.0%,and 73.8%,respectively,and the AUC was 0.735.The sensitivity,specificity,and accuracy of muscle infiltration were determined by T2 WI plus DWI.82.5%,84.0%,83.1%,AUC was 0.832;the sensitivity,specificity and accuracy of T2 WI plus DWI plus DCE to determine myometrial invasion were 90.0%,92.0%,90.8%,and AUC was 0.910;The accuracy of the test was 0.026,which was considered statistically significant.The area under the curve(AUC)of the Z test was 0.033,and the difference was considered statistically significant.ConclusionConventional MRI(T1,T2)combined with DWI and DEC as a bladder cancer staging tool is feasible.If our data is validated,mpMRI can be performed prior to TUR and can be assessed using the VIRADS scoring system to identify MIBC faster and speed up the treatment process.