To determine the optimal cystoscopic interval for intermediate-risk nonmuscle invasive bladder cancer (IR-NMIBC).
A retrospective analysis of IR-NMIBC patients (2010-2017) was performed and 3 hypothetical models of surveillance intensity applied: Model 1: high (3-months), Model 2: moderate (6-months) and Model 3: low-intensity (12-months) over a 2-year period and we compared timing of actual detection of recurrence and progression to proposed cystoscopy timing between each model. We calculated number of avoidable cystoscopies and associated costs.
Of 107 patients with 37 months median follow-up, 66/107 (77.6%) developed recurrence and 12/107(14.1%) had progression. Relative to model 1, there were 33 (50%) delayed detection of recurrences in model 2 and 41 (62%) in model 3. There was 1.7 months mean delay in detection of recurrence for model 1 vs 3.2 and 7.6 months for model 2 and 3 (p<0.001 Model 1 vs 2; p<0.001 Model 2 vs 3). Relative to model 1, there were 8(67%) and 9(75%) delayed detection of progression events in model 2 and 3. There were no progression-related bladder cancer deaths or radical cystectomy due to delayed detection. Mean number of avoidable cystoscopies was higher in model 1 (2) vs model 2 (1) and 3 (0) respectively. Model 1 had the highest aggregate cost of surveillance ($46,262.52).
High-intensity (3-month) surveillance intervals provides faster detection of recurrences but with increased cost and more avoidable cystoscopies without clear oncologic benefit. Moderate intensity (6-month) intervals in IR-NMIBC allows timely detection without oncologic compromise and is less costly with fewer cystoscopies.
The Journal of urology. 2021 Feb 22 [Epub ahead of print]
Abhishek Bhat, Deukwoo Kwon, Nachiketh Soodana-Prakash, Ali Mouzannar, Sanoj Punnen, Mark L Gonzalgo, Dipen J Parekh, Chad R Ritch
Department of Urology, University of Miami Miller School of Medicine, Miami, Florida., Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, Florida.