POINT OF CARE URINALYSIS IN PATIENTS WITH RENAL CELL CARCINOMA HAS PROGNOSTIC VALUE

Introduction

Multiple prognostic models have been developed to help stratify patients with renal cell carcinoma (RCC) for the purposes of patient counseling and treatment selection. Utilization of histological features in these models, however, limits their application to the postoperative setting. A point of care (POC) urinalysis (UA) is a ubiquitous test in the field of urology and a standard part of the diagnostic workup for a renal mass in both the American Urological Association (AUA) and the European Association of Urology (EAU) guidelines. We sought to characterize the prevalence of abnormalities on preoperative UA among patients undergoing extirpative surgery for RCC, and whether presence of these factors impacts overall (OS) and cancer-specific survival (CSS).

Methods

Emory's prospectively maintained nephrectomy database was retrospectively reviewed for any stage, major histology (clear cell, chromophobe, papillary) RCC patients who underwent partial or radical nephrectomy from 2001-2022. Patient and pathologic characteristics were recorded for patients who had a UA within 90 days before surgery. Abnormal UA laboratory values were defined as specific gravity outside 1.005–1.030, ≥ +1 blood, and any protein, leukocyte esterase, glucose, or nitrites. Patients were categorized based on preoperative UA results: no abnormalities, 1 abnormality, and >1 abnormality. Primary outcomes of interest were OS and CSS. Kaplan-Meier curves and multivariable COX Hazards models were utilized to evaluate OS and CSS. Each UA component was assessed in individual multivariable models to determine specific associations with survival.

Results

A total of 1607 patients were evaluated: 644 (40.1%) had a normal UA, 508 (31.6%) had 1 abnormal UA component, and 455 (28.3%) had > 1 abnormal UA component. Univariable Kaplan Meier curves for ten-year OS and CSS based on the number of abnormalities on POC UA is shown in Figure 1. The presence of > 1 abnormal preoperative UA component was associated with worse OS (HR 1.67, p < 0.001) and CSS (HR 1.85, p < 0.001; Table 1). Blood (HR 1.34, p < 0.001), protein (HR 1.61, p < 0.001), and nitrites (HR 2.17, p = 0.002) were all independently associated with worse OS. Blood (HR 1.48, p = 0.002), protein (HR 1.49, p = 0.002), nitrites (HR 2.43, p = 0.012), and leukocyte esterase (HR 1.46, p = 0.009) were all independently associated with worse CSS.

Conclusions

 A POC UA is easily accessible in the preoperative settings and adds little to no cost, with abnormalities associated with a higher risk of all-cause and cancer-specific mortality for patients with RCC undergoing nephrectomy. Specifically, abnormalities in blood, protein, nitrites, and leukocyte esterase were found to be independently associated with worse survival. Future research should examine whether resolution of UA abnormalities is associated with improved survival and investigate if the addition of UA abnormalities increases the prognostication of current models.