Abstract Vesical Imaging–Reporting and Data System (VI-RADS) has been recently proposed for standardizing magnetic resonance imaging (MRI) reporting in bladder cancer. In this single-center prospective observational study, we sought to compare the diagnostic accuracy of biparametric MRI (BP-MRI) and multiparametric MRI (MP-MRI) in detection of detrusor muscle invasion by bladder cancer using VI-RADS. Patients with bladder cancer underwent MRI on a 3 Tesla scanner. Tumors were scored on T2-weighted images (T2WI), diffusion-weighted imaging (DWI), and dynamic contrast enhanced (DCE) imaging according to VI-RADS. Results of BP-MRI and MP-MRI were compared taking histopathology as the gold standard. Receiver operating characteristic (ROC) curve analysis was used to find out the cut-off point of VI-RADS for predicting detrusor muscle invasion by bladder cancer. Diagnostic tests were used to calculate sensitivity and specificity of BP-MRI and MP-MRI for detecting muscle-invasive bladder cancer (MIBC) for each VI-RADS cutoff. A total of 30 patients with bladder cancer were evaluated using MRI. Using the ROC curve, the cut-off for both BP-MRI and MP-MRI VI-RADS for predicting MIBC was determined to be ≥3. Area under the ROC curves (AUROC) of BP-MRI and MP-MRI were 0.866 and 0.861, respectively, the difference being statistically insignificant (DeLong's test p = 0.900). BP-MRI and MP-MRI also had equal sensitivity (95.5%) and specificity (75.0%) at the cut-off of VI-RADS score ≥3. On account of their similar diagnostic accuracy, BP-MRI appears to be a feasible alternative to MP-MRI in detection of detrusor muscle invasion by bladder cancer.
Kaushik et al. (Tue,) studied this question.