Considering the Effects of Modern Point-of-Care Urine Biomarker Assays in Follow-Up of Patients with High-Risk Non-muscle-Invasive Bladder Cancer

Abstract

Background: Although a plethora of urine markers for diagnosis and follow-up of patients with bladder cancer (BC) has been developed and studied, the clinical impact of urine testing on patient management remains unclear. The goal of this manuscript is to identify scenarios for a potential use of modern point-of-care (POC) urine marker assays in the follow-up of patients with high-risk non-muscle-invasive BC (NMIBC) and estimate potential risks and benefits.

Methods: To permit comparison between different assays, the results of 5 different POC assays studied in a recent prospective multicenter study including 127 patients with suspicious cystoscopy undergoing TURB were used for this simulation. For the current standard of care (SOC), a "marker-enforced" procedure, and a combined strategy sensitivity (Se), estimated number of cystoscopies, and the numbers needed to diagnose (NND) over a 1-year follow-up period were calculated.

Results: For regular cystoscopy (SOC), a Se of 91.7% and a NND of 42.2 repetitive office cystoscopies (WLCs) for 1 recurrent tumor at 1 year were calculated. For the "marker-enforced" strategy, marker sensitivities between 94.7% and 97.1% were observed. The "combined" strategy yielded for markers with a Se exceeding 50% an overall Se at 1 year similar or superior to the current SOC. Savings regarding the number of cystoscopies in the "marker-enforced" strategy vs. the SOC were small, while, depending on the marker, up to 45% of all cystoscopies may be saved using the "combined" strategy.

Conclusions: Based on the results of this simulation, a marker-supported follow-up of patients with high-risk (HR) NMIBC is safe and offers options to significantly reduce the number of cystoscopies without compromising the Se. Further research focusing on prospective randomized trials is needed to finally find a way to include marker results into clinical decision-making.

Keywords: Bladder cancer; Diagnosis; Disease management; Follow-up; Surveillance; Urinary tumor markers.