Role of multiparametric magnetic resonance imaging in the diagnosis and staging of urinary bladder cancer

Objectives:To assess the role of multiparametric magnetic resonance imaging(mp-MRI)in the diagnosis and staging of urinary bladder cancer(BC).Materials and methods:Fifty patients diagnosed with bladder masses underwent mp-MRI study.The results of 3 image sets were analyzed and compared with the histopathological results as a reference standard:T2-weighted image(T2WI)plus dynamic contrast-enhanced(DCE),T2WI plus diffusion-weighted images(DWI),and mp-MRI,including T2WI plus DWI and DCE.The diagnostic accuracy of mp-MRI was evaluated using receiver operating characteristic curve analysis.Results:The accuracy of T2WI plus DCE for detecting muscle invasion of BC was 79.5%with a fair agreement with histopathological examination(κ=0.59);this percentage increased up to 88.6%using T2WI plus DWI,with good agreement with histopathological examination(κ=0.74),whereas mp-MRI had the highest overall accuracy(95.4%)and excellent agreement with histopathological data(κ=0.83).Multiparametric MRI can differentiate between low-and high-grade bladder tumors with a high sensitivity and specificity of 93.3%and 98.3%,respectively.Conclusions:Multiparametric MRI is an acceptable method for the preoperative detection and accurate staging of BC,with reasonable accuracy in differentiating between low-and high-grade BC.