TITLE:
MRI of the Bladder in Patients Suspected of Bladder Tumors
AUTHORS:
Karen Lind Gandrup, Jørgen Nordling, Henrik S. Thomsen
KEYWORDS:
Urography, Diagnostic Imaging, Hematuria, Magnetic Resonance Imaging, Cystoscopy
JOURNAL NAME:
Open Journal of Radiology,
Vol.4 No.2,
June
17,
2014
ABSTRACT: Objective: To
prospectively evaluate the use of MRI for the detecting of bladder tumors and
the T- stage using T2W, T1W and diffusion-weighted images (DWI). Material and
methods: Twenty-eight consecutive patients (21 men, 7 women; age range, 20 - 82
years; mean age, 62.8 years) suspected of bladder tumors underwent MRI,
flexible cystoscopy and transurethral resection (TURB). The presence of bladder
tumor was confirmed by histopathology in 21 patients; 18 patients had pTa, one
pT1 and two pT2. The images were reviewed by two uroradiologists. They assigned
the presence of a bladder tumor and whether the tumor was non-muscle invasive
(Ta and T1) or muscle- invasive (T2, T3 or T4). Results: Compared to the
histopathological results, the accuracy for identifying a bladder tumor was
60.7% and 53.7% for reviewer A and B, respectively. The sensitivity and
specificity were 66.7%/61.9% and 57.1%/42.9%. Positive predictive values were
82.6%/ 76.5%. The overall staging was correct in 47.6%/52.5%, but improved on
stage-by-stage up to 50%/66.7%. The agreement between the reviewers was
moderate in the detecting, staging and location of the tumor (Kappa = 0.47 - 0.57).
Conclusion: A simple MRI using no contrast media, but DWI, cannot replace
flexible cystoscopy in the detection of new or recurrent bladder tumors.