Diagnostic Performance of Urinary Dipstick Test for Haematuria in Low-Risk Non-Muscle-Invasive Bladder Cancer Surveillance

Background/Objectives: Low-risk non-muscle-invasive bladder cancer (NMIBC) is associated with extremely low rates of progression and cancer-specific mortality. Current surveillance strategies recommend yearly cystoscopic surveillance after the initial 12-month period. Cystoscopic surveillance is costly, leading bladder cancer to be one of the most economically burdensome diseases. We investigated the use of a negative urinary dipstick for haematuria (UDH) in predicting the absence of recurrence. Methods: All patients undergoing flexible cystoscopy at our institution underwent urinary dipstick testing immediately prior to their procedures. We conducted a retrospective analysis of all patients undergoing cystoscopic surveillance for known low-risk NMIBC at our institution between January 2018 and August 2024. All patients had low-risk NMIBC, as defined by American Urological Association (AUA) guidelines, at the time of flexible cystoscopy. Patient demographics, cystoscopy operation records, and subsequent biopsy results were reviewed. Results: A total of 124 patients who underwent 310 cystoscopies were included in the analysis. The overall rate of UDH positivity was 54%. The negative predictive value (NPV) and sensitivity of UDH for the absence of bladder cancer recurrence were 95.7% and 81.2%, respectively. All cases of bladder cancer recurrence with negative UDH were low-grade Ta (n = 5) or papillary urothelial neoplasm of low malignant potential (PUNLMP) (n = 1). There was no difference in the NPV and sensitivity within 12 months of diagnosis (NPV = 95.4%, sensitivity = 83.3%) and 12 months after diagnosis (NPV = 95.8%, sensitivity = 80%). Conclusions: UDH has a high NPV and sensitivity for recurrence in low-risk NMIBC. No cases of high-grade tumors or carcinoma in situ were undetected by UDH in this study. UDH shows promise as an inexpensive adjunct test that can reduce the high economic burden of surveillance of non-muscle-invasive bladder cancer.