Imaging Surveillance of Invasive Bladder Cancer with Bladder Preservation

Purposes: To evaluate the diagnostic accuracy of abdominopelvic ultrasound (US), virtual cystoscopy (VC) and MRI diffusion (MRI DWI) with conventional cystoscopy (CC), in the detection and characterization of bladder lesions after transurethral resection (TURT). Methods: Forty-five patients with a history of high-grade T1 or T2-T4a bladder cancer who underwent TURT and received chemoradiation schedule. They were followed-up by serial cystoscopies. Before each cystoscopy, the patients underwent bladder ultrasound, CT-based virtual cystoscopy, and diffusion-weighted MRI. The results of these three non-invasive modalities are compared with those of cystoscopy and with histological findings obtained by (repeat) transurethral resection. Sensitivity, specificity, positive and negative predictive values, and accuracy were calculated and compared to CC and histopathology as the gold standard. Results: After median 24 months of follow up, US, CT VC, and MRI DWI detected 23,28 and 29 lesions respectively of the 30 lesions detected at CC. pathology confirmed local recurrence in 18 lesions (40%) and benign changes in 12 lesions (27%), while remaining 15 patients were negative. Eighteen lesions (60 %) were larger than 1 cm, twenty-three lesions showed polypoidal morphology (77 %). The diagnostic accuracy of US, CT VC, MRI DWI was 73%, 93%, and 93 % respectively. (P>0.10). MRI DWI had highest NPV of 93%.   Conclusion: Imaging surveillance in bladder cancer preservation should include MRI DWI as part of the surveillance programme to reduce the frequency of cystoscopy. MRI and CT VC were of comparable accuracy, US had the lowest sensitivity, however, it is still can be used as the first step of surveillance.   Funding Statement: No funding received. Declaration of Interests: Authors declare no conflict of interest. Ethics Approval Statement: Written consent was taken from patients participating in the study. The study protocol was approved by the local institutional review board (IRB:IORG0006563)