Prospective evaluation of a urinary biomarker panel to detect and predict recurrence of non-muscle-invasive bladder cancer

Abstract

Purpose To perform a feasibility phase study of a panel of putative protein biomarkers and determine whether it can identify and predict tumor recurrence in patients with non-muscle-invasive bladder cancer (NMIBC) on follow-up. Methods We prospectively analyzed the urine of 152 patients previously treated for NMIBC. Quantitative expression of plasminogen activator inhibitor-1 (PAI-1), DJ-1, apolipoprotein A-I (apoA-1), matrix metallopeptidase-9 (MMP-9), and interleukin-8 (IL-8) was assessed by enzyme-linked immunosorbent assay and compared amongst patients with and without bladder cancer recurrence at urine collection and during 3 years of follow-up. Tumor recurrence was confirmed by pathologic analysis. We performed a prediction analysis, excluding patients with recurrence at the start of the study, and assessed the influence of previous use of intravesical BCG on the level of biomarkers. Results Median follow-up time was 47 months (interquartile range 39-50 months). Sixteen patients (10.5%) were diagnosed with recurrence at the start of the study, and 21 (15.4%) were diagnosed during the study. Three biomarker proteins (apoA-1, MMP-9, and IL-8) appear to hold diagnostic potential [odds ratio (OR) = 12.9; 95% CI 3.5-47.4]; while, PAI-1 and IL-8 predict recurrence (OR = 4.1; 95% CI 1.4-11.4). Previous use of intravesical BCG did not affect biomarker levels. Conclusion In the feasibility phase, the panel of urine biomarkers analyzed detected and predicted recurrence of NMIBC and provided reliable results in patients who had previously used intravesical BCG. Validation studies are required to confirm the panel clinical utility.