urinary aquaporin-1 in RCC
Purpose: To determine the sensitivity and specificity of urinary aquaporin-1(uAQP-1) to diagnose renal cell carcinoma(RCC) and to establish baseline concentrations of this marker in our population. Methods: A total of 72 participants were planned for enrollment with equal number of cases and healthy controls in a prospective two-gated design. Cases were enrolled from those who had an imaged renal mass, suspicious of RCC who were planned for surgery, while controls were selected from prospective voluntary kidney donors. uAQP-1 concentrations were estimated with a sandwich ELISA and normalized by measuring spot urine creatinine. A receiver operator curve was drawn to analyze the diagnostic accuracy of uAQP-1 for RCC. Results: At the end of the study duration, 60 participants were enrolled. The median uAQP-1 concentrations among the imaged renal masses was 8.78ng/mg creatinine (IQR -7.11). Among healthy controls median uAQP-1 concentration was 9.52 ng/mg creatinine (IQR-6.89). The sensitivity and specificity of the test was 47.2% and 66.7%% respectively, and area under the curve was 0.52. Results indicated that this test did not discriminate between healthy individuals and patients with RCC. Conclusion: uAQP-1 is not a suitable biomarker for renal cell carcinoma in the study population.