(HealthDay News) — Urine aquaporin-1 (AQP1) and perilipin-2 (PLIN2) seem to have utility as biomarkers for diagnosing malignant clear cell or papillary renal cell carcinoma (RCC) in a screening paradigm, according to a study published online March 19 in JAMA Oncology.
Jeremiah J. Morrissey, Ph.D., from Washington University in St. Louis, and colleagues examined the clinical utility, sensitivity, and specificity of AQP1 and PLIN2 concentrations as biomarkers for RCC. Urine samples were obtained from 720 patients undergoing routine abdominal computed tomography (CT) screening (screening population), 80 healthy controls, and 19 patients with pathologically-confirmed RCC.
The researchers found that all patients with known RCC had significantly higher urine AQP1 and PLIN2 concentrations (P < 0.001) compared with the healthy controls and the screening population. For urine AQP1 and PLIN2 concentrations individually or in combination, the area under the receiver operating characteristic curve was 0.990 or greater, with sensitivity of 95% or higher and specificity of 91% or greater compared with controls or the screening population. 3 of the 720 screened patients had biomarker concentrations indicative of RCC and they were found to have an imaged renal mass on CT. On further evaluation, two patients had pathologically confirmed RCC.
“These tumor-specific proteins have high clinical validity and substantial potential as specific diagnostic and screening biomarkers for clear cell or papillary RCC and in the differential diagnosis of imaged renal masses,” the authors write.
Two authors have a European patent on the use of urine AQP1 to diagnose renal cancer.