Preoperative predictors of renal failure after robot-assisted partial nephrectomy: Analysis of the Vattikuti Global Quality Initiative in Robotic Urologic Surgery (GQI-RUS) database

INTRODUCTION & OBJECTIVES: Previous studies assessed predictors of kidney failure after partial nephrectomy. However, evidence is
scarce regarding the impact of preoperative patient characteristics on the risk of renal failure after Robot-Assisted Partial Nephrectomy
(RAPN) in patients with Renal Cell Carcinoma (RCC) and normal preoperative renal function.
MATERIAL & METHODS: We evaluated 243 patients treated with RAPN for RCC at 10 worldwide centers between 2008 and 2013 included
in the Vattikuti Global Quality Initiative in Robotic Urologic Surgery (GQI-RUS) database. All patients included in the study had normal
preoperative kidney function, as defined by an estimated GFR (eGFR) ≥90 mL/min/1.73m2. Renal failure after RAPN was defined as a
decrease in the eGFR ≥25%. Uni- and multi variable logistic regression analyses assessed the impact of preoperative patient and disease
characteristics on the risk of renal failure after surgery. In particular, covariates consisted of age at surgery, preoperative eGFR, PADUA
score, Charlson co morbidity index, and gender.
RESULTS: Median age at surgery was 51 years. Median preoperative eGFR and BMI were 103 mL/min/1.73m2 and 29, respectively.
Median PADUA score and clinical tumour size were 8 and 34.0 mm, respectively. Overall, 153 (63.0%) vs. 90 (37.0%) patients were male
vs. female, respectively. Overall, 99 (40.7%) patients experienced kidney failure immediately after RAPN. In uni variable analyses, age at
surgery, PADUA-score and baseline eGFR were significantly associated with the risk of postoperative kidney failure (all P<0.01). In multi
variable analyses, older age (Odds Ratio [OR]: 1.05; 95% confidence interval [CI]: 1.01-1.11; P=0.04) and higher PADUA-score (OR: 1.34;
95% CI: 1.02-1.78; P=0.04) represented independent predictors of kidney failure after RAPN.
CONCLUSIONS: Age and PADUA-score represent independent preoperative predictors of kidney failure after RAPN in patients with RCC
and normal kidney function. These parameters should be considered when planning the surgical approach and counselling patients with
regards to the risk of renal surgery.