Open AccessMultiparametric MRI for Bladder Cancer: Validation of VI-RADS for the Detection of Detrusor Muscle Invasion
Author(s) -
Huanjun Wang,
Cheng Luo,
Fan Zhang,
Jian Guan,
Shurong Li,
Haohua Yao,
Junxing Chen,
Junhang Luo,
Lingwu Chen,
Yan Guo
Publication year - 2019
Publication title -
radiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.118
H-Index - 295
eISSN - 1527-1315
pISSN - 0033-8419
DOI - 10.1148/radiol.2019182506
Subject(s) - medicine , interquartile range , bladder cancer , detrusor muscle , magnetic resonance imaging , receiver operating characteristic , retrospective cohort study , cancer , radiology , urology , urinary bladder , pathology , surgery
Background The Vesical Imaging-Reporting and Data System (VI-RADS) scoring system was created in 2018 to standardize imaging and reporting of bladder cancer staging with multiparametric MRI. The system provides a five-point VI-RADS score, which suggests the likelihood of detrusor muscle invasion. Muscle-invasive disease carries a worse prognosis and requires radical surgery. Purpose To determine the performance of the VI-RADS score in detecting muscle-invasive bladder cancer in a cohort of patients undergoing multiparametric MRI before surgery. Materials and Methods In this retrospective study, a total of 340 patients with bladder cancer were identified from a database of consecutive patients undergoing multiparametric MRI from November 2011 to August 2018. The tumor with the largest burden was selected in those patients with multifocal tumors. Bladder tumors were retrospectively categorized according to the VI-RADS five-point scoring system by two readers, independently and in consensus, who were blinded to histologic findings. The VI-RADS score was compared with postoperative pathology for each tumor, and the performance of VI-RADS for determining detrusor muscle invasion was analyzed by using the Cochran-Armitage test. Results Among the 340 patients, there were 296 men and 44 women; the median age was 64.0 years (interquartile range [IQR], 57.0-87.0 years). Of 340 tumors, 255 (75.0%) were verified as non-muscle-invasive and 85 (25.0%) as muscle-invasive bladder cancer. Both the VI-RADS score and its components were associated with muscle-invasive condition ( P < .001). The area under the receiver operating characteristic curve for VI-RADS for muscle invasion was 0.94 (95% confidence interval [CI]: 0.90, 0.98). The sensitivity and specificity of a VI-RADS score of 3 or greater were 87.1% (95% CI: 78%, 93%) and 96.5% (95% CI: 93%, 98%), respectively. Conclusion The Vesical Imaging-Reporting and Data System score effectively defines the likelihood of detrusor muscle invasion in bladder cancer and should be considered for evaluation of tumors prior to surgery. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Margolis and Hu in this issue.