Background
Due to the faltering sensitivity and/or specificity, urine-based assays currently have a limited role in the management of patients with bladder cancer (BCa). The aim of this study was to externally validate our previously reported protein biomarker panel from multiple sites in the US and Europe.
Methods
This multicenter external validation study included a total of 320 subjects (BCa = 183). The 10 biomarkers (IL8, MMP9, MMP10, SERPINA1, VEGFA, ANG, CA9, APOE, SDC1 and SERPINE1) were measured using commercial ELISA assays in an external laboratory. The diagnostic performance of the biomarker panel was assessed using receiver operator curves (ROC) and descriptive statistical values.
Results
Utilizing the combination of all 10 biomarkers, the AUROC for the diagnostic panel was noted to be 0.847 [95% CI: 0.796 – 0.899], outperforming any single biomarker. The multiplex assay at optimal cutoff value achieved an overall sensitivity of 0.79, specificity of 0.79, PPV of 0.73 and NPV of 0.84 for BCa classification. Sensitivity values of the diagnostic panel for high-grade BCa, low-grade BCa, MIBC and NMIBC were 0.81, 0.90, 0.95 and 0.77, respectively.
Conclusions
Urinary levels of the biomarker panel enabled discrimination of BCa patients and controls, and the levels of biomarker subsets were associated with advancing tumor grade and stage.
Impact
If proven to be reliable, urinary diagnostic biomarker assays can detect BCa in a timely manner such that the patient can expect improvements in overall survival and quality of life.