# The GreenBladder Study: Early Detection of Bladder Cancer in Greenland Using a Urinary Biomarker

## TL;DR

A urinary test for bladder cancer showed promise in Greenland, where access to traditional diagnostics is limited, potentially helping detect cancer earlier.

## Contribution

The study evaluates the Xpert® Bladder Cancer Detection test as a triage tool in a low-prevalence, resource-limited setting.

## Key findings

- XBCD had a sensitivity of 71.4% and specificity of 88.8% in detecting bladder cancer.
- The test's negative predictive value was 98.8%, suggesting it could reduce unnecessary cystoscopies.
- Findings are limited by the small number of cancer cases detected (seven).

## Abstract

Background: Bladder cancer (BC) incidence in Greenland is lower than in other Nordic countries, yet mortality is disproportionately high, suggesting delayed detection. Cystoscopy is the diagnostic gold standard to detect BC, but access in Greenland is often limited by geographic and logistical challenges, underscoring the need for more accessible diagnostic tools. Objectives: This study evaluated the performance of the urinary biomarker test Xpert® Bladder Cancer Detection (XBCD) among patients referred for cystoscopy within the Greenlandic healthcare system. Methods: In this prospective observational study, 198 patients referred for urological evaluation due to hematuria or other urologic symptoms were recruited from five Greenlandic towns. All participants provided a urine sample for XBCD testing prior to cystoscopy, which served as the reference standard. Results: Among 194 patients with valid test results, seven BC cases were detected. XBCD identified five true positives and 166 true negatives, yielding a sensitivity of 71.4%, specificity of 88.8%, and a negative predictive value of 98.8%. Conclusions: In this low-prevalence setting, XBCD demonstrated potential as a triage tool to reduce the number of procedures and support earlier BC detection, although findings are limited by the small number of cancer cases.