The Value of Negative Urinary Dipstick Tests for Haematuria in Patients Undergoing Surveillance for Low-grade Ta Urothelial Cancer: A Two-stage Prospective Clinical Study in 524 Patients

Abstract

Background and objectiveThe risk of first recurrence beyond 5 yr for patients with low-grade (LG) Ta non–muscle-invasive bladder cancer (NMIBC) is low enough to consider discontinuing cystoscopic surveillance at that point. However, a positive urinary dipstick test for haematuria (UDH) during and beyond the period of cystoscopic surveillance can disrupt plans to cease surveillance because the association between UDH positivity and recurrence in LG Ta NMIBC is unknown. In a two-stage study, we evaluated this association and explored the role of UDH negativity in predicting the absence of recurrence. MethodsBecause of previously demonstrated changes in recurrence patterns over time, two prospective cohorts were assessed: an “exploratory” cohort (January 2007–March 2008) and a “validation” cohort (November 2017–August 2018). UDH was performed before flexible cystoscopy. Patient, operative, and surveillance data have been recorded prospectively using standard pro forma sheets since 1978 in our institution. Only patients with primary LG Ta pTa NMIBC were included for analysis. Key findings and limitationsWe assessed 231 patients in the exploratory group and 293 in the validation group. The proportion of smokers (67% vs 70%; p = 0.5) and mean follow-up (72.2 vs 79.9 mo; p = 0.2) were similar between the groups. The recurrence rate was higher in the exploratory group (19% vs 11%; p = 0.009), as was the UDH positivity rate (37% vs 11%; p < 0.001). The specificity and negative predictive value were 64% and 83% in the exploratory group, and 90% and 90%, respectively, in the validation group. These values increased further for the subgroup with solitary primary tumours the subgroup without recurrence for 3 yr. Conclusions and clinical implicationsUDH negativity has a high probability of being associated with the absence of recurrence in small LG Ta NMIBC and could be an inexpensive adjunct during surveillance. Ongoing validation, which started in 2019, is being performed in a now-nationalised Scottish protocol in which UDH replaces cystoscopy in years 2 and 4 for patients in the low-risk group. Patient summaryWe investigated the accuracy of a dipstick test for blood in the urine for patients undergoing surveillance for low-grade noninvasive bladder cancer. We found that a negative dipstick test result was highly associated with the absence of tumour recurrence, particularly for patients with the lowest risk. These findings have been introduced into a national protocol designed to reduce the frequency of telescopic inspection of the bladder during surveillance to reduce the burden for patients.