Abdom Radiol (NY). December 17, 2021. doi: 10.1007 / s00261-021-03383-3. Online ahead of print.

ABSTRACT

OBJECTIVE: (1) To assess the accuracy and validity of biparametric MRI (bp-MRI), including T2-weighted (WI) and DWI image sequences, and the availability of an alternative to multiparametric MRI (Mp-MRI), for the assessment of muscle invasiveness in bladder cancer (BC). (2) To assess the diagnostic performance and agreement of readers with different experiences in abdominal imaging to the use of the two protocols.

Methods: Preoperative mp-MRI of the bladder was performed in 128 patients with an initial diagnosis of CB. Two sets of images, Series 1 (bp-MRI) and Series 2 (mp-MRI), were evaluated independently by both readers. Descriptive statistics, including sensitivity, specificity, precision, and area under the curve (AUC), for VI-RADS scores were calculated using ≥ 4 as the muscle invasion threshold for each reader and set of ‘images. Interreader agreement was assessed using Cohen’s kappa coefficient.

RESULTS: Sensitivity varied between 90.3-93.5% and 87.1-90.3%, specificity varied between 96.6-99.1% and 91.6-96.6%, precision varied between 96-97.3% and 91.3-94.6%, and AUC ranged between 0.947-0.951 and 0.919-0.921, for bp-MRI and mp-MRI, and reader 1 and reader 2, respectively. No significant difference was shown in diagnostic performance for either reader between the two protocols (p = 0.238 and 0.318). There was excellent agreement between readers in VI-RADS scores, using both protocols.

CONCLUSION: A pb-MRI protocol has comparable diagnostic accuracy to an mp-MRI protocol for the detection of muscle invasive BC using the VI-RADS criteria. Additionally, in both MRI protocols, the reader’s experience does not appear to significantly affect diagnostic performance when using the VI-RADS criteria.

IDPM: 34919161 | DOI: 10.1007 / s00261-021-03383-3