(UroToday.com) The 2025 European Association of Urology (EAU) Annual Congress held in Madrid, Spain between March 21st and 24th 2025, was host to an abstract session on the latest advances in the diagnosis and follow-up of non-muscle invasive bladder cancer (NMIBC). Dr. Thomas Dreyer presented the results of the DaBlaCa-15 randomized trial evaluating the urinary biomarker test, Xpert® Bladder Cancer Monitor, for guiding performance of cystoscopy in the surveillance of high-grade NMIBC.
NMIBC surveillance strategies incorporate frequent cystoscopies due to the high risk of disease recurrence and progression. Urinary biomarkers have long been touted as a non-invasive alternative to reduce the costs and morbidity associated with frequent cystoscopies. However, the clinical impact/utility of urinary biomarkers remains unclear due to the paucity of level one evidence from randomized clinical trials.
DaBlaCa-15 is a randomized, non-inferiority trial designed to evaluate Xpert® Bladder Cancer Monitor (CE-IVD, In Vitro Diagnostic Medical Device) for reducing the number of cystoscopies required during the follow-up of high-grade NMIBC patients. Patients in the intervention arm underwent Xpert® Bladder Cancer Monitor urinary tests to guide decisions on whether cystoscopy was needed, while patients in the control arm underwent cystoscopy at all follow-up visits.The primary study outcome was recurrence-free survival, which include high-grade NMIBC recurrences, progression to muscle-invasive bladder cancer (MIBC), and/or development of metastatic urothelial carcinoma. Recurrence rates were compared by calculating the risk difference between the two study arms.
A total of 392 patients were enrolled in the trial. Forty-three high-grade recurrences were detected across the two arms: 22 recurrences (11.6%) in the intervention arm versus 21 recurrences (11.2%) in the control arm. The calculated risk difference between the two study arms was 0.08% (95% CI: -7.2 to 7.4%), indicating no significant difference in recurrence rates between the two surveillance strategies.
With regards to disease progression, two patients in the intervention arm experience disease progression: one to MIBC and another who developed metastatic disease. In contrast, three patients in the control arm progressed to MIBC.
Patients in the intervention arm underwent significantly fewer cystoscopies (445 cystoscopies, 44.2%) compared to those in the control arm (1,029 cystoscopies, 98.8%; p< 0.001).
Dr. Dreyer noted that the results of the DaBlaCa-15 trial provide high-level evidence supporting the use of the Xpert® Bladder Cancer Monitor test in the follow-up of high-grade NMIBC patients. These findings demonstrate that alternating flexible cystoscopy with the Xpert® Bladder Cancer Monitor test is oncologically safe, with no increase in the risk of disease progression. Furthermore, patients in the intervention arm underwent a significantly lower number of cystoscopies, suggesting that the Xpert® Bladder Cancer Monitor test can reduce the burden of invasive procedures without compromising patient outcomes.
The study's findings are particularly relevant given the current burden of bladder cancer surveillance. Cystoscopy is an invasive procedure that carries both cost and morbidity, and while its importance in detecting recurrences is well-established, there remains a need for more efficient and less invasive alternatives. The Xpert® Bladder Cancer Monitor test appears to meet this need by offering a non-invasive approach for detecting recurrence with comparable sensitivity to cystoscopy.
However, the study's limitations should be noted. The recurrence rate in both study arms was lower than expected, which may have impacted the study's ability to fully assess the test’s diagnostic accuracy. Additionally, while the study design suggests non-inferiority, long-term follow-up is necessary to fully evaluate the test's effectiveness in a broader patient population.
Presented by: Thomas Dreyer, MD, PhD, Department of Urology, Aarhus University Hospital, Aarhus, Denmark
Written by: Rashid K. Sayyid, MD, MSc – Robotic Urologic Oncology Fellow at The University of Southern California, @rksayyid on Twitter during the 2025 European Association of Urology (EAU) Annual Congress held in Madrid, Spain between March 21st and 24th, 2025