title: Potential Utility of Diffusion-Weighted Magnetic Resonance Imaging in Diagnosis of Residual Bladder Cancer before Second Transurethral Resection.
abstract: BACKGROUND
  The study aimed to investigate the diagnostic utility of diffusion-weighted MRI (DW-MRI) in differentiating residual bladder cancer from benign postoperative changes before a second transurethral resection of the bladder (TURB).
  
  
  METHODS
  Of the 75 bladder cancer patients who underwent a second TURB from 2013 to 2015, 23 patients who underwent multi-sequence bladder MRI after their initial TURB were retrospectively evaluated. Thirty lesions were histologically examined at the second TURB and the results of them were compared with the findings obtained through T2-weighted MRI, dynamic contrast-enhanced MRI (DCE-MRI), and DW-MRI.
  
  
  RESULTS
  Positive findings of 27, 28, and 15 lesions showed up on T2W-, DCE-, and DW-MRI, respectively. Thirteen lesions were confirmed histologically to constitute residual cancer. The sensitivity/specificity/accuracy of T2W-, DCE-, and DW-MRI were 100/18/53, 100/12/50, and 92/82/87%, respectively. DW-MRI was significantly superior in specificity and accuracy to T2W- (p < 0.01 for both) and DCE-MRI (p < 0.01 for both).
  
  
  CONCLUSIONS
  This study first showed the superiority of DW-MRI to T2W- and DCE-MRI in differentiating residual cancer before a second TURB.
authors.affiliation: Department of Urology, Tokyo Medical and Dental University Graduate School, Tokyo, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Soichiro
authors.initials: S
authors.lastname: Yoshida
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tanaka
authors.forename: Masaharu
authors.initials: M
authors.lastname: Inoue
authors.forename: Masaya
authors.initials: M
authors.lastname: Ito
authors.forename: Toshiki
authors.initials: T
authors.lastname: Kijima
authors.forename: Minato
authors.initials: M
authors.lastname: Yokoyama
authors.forename: Junichiro
authors.initials: J
authors.lastname: Ishioka
authors.forename: Yoh
authors.initials: Y
authors.lastname: Matsuoka
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Saito
authors.forename: Yasuhisa
authors.initials: Y
authors.lastname: Fujii
authors.forename: Kazunori
authors.initials: K
authors.lastname: Kihara
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media / Q000737:chemistry; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018365:Neoplasm, Residual / Q000000981:diagnostic imaging* / Q000601:surgery*; D012086:Reoperation; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D001743:Urinary Bladder / Q000473:pathology; D001749:Urinary Bladder Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery*
chemical_list: D003287:Contrast Media