Predictors of early postoperative and mid-term functional outcomes in patients treated with Endoscopic Robot-Assisted Simple Enucleation (ERASE): results from a tertiary referral center.

Background: The aim of this study was to assess the early and mid-term functional outcomes of Endoscopic Robot Assisted Simple Enucleation (ERASE) verified through a standardized tumor-resection reporting system (Surface Intermediate Base [SIB] score) and to investigate for predictors of renal function (RF) loss in patients with T1 renal tumors treated in a tertiary referral institution.

Methods: Data of 553 patients treated with ERASE were analyzed. Only patients with SIB score of 0-1 and negative oncological follow-up were included. A ≥25% drop from baseline of estimated glomerular filtration rate (eGFR) was considered as a clinically meaningful functional loss. Multivariable regression models tested the relation between clinical features and RF loss at postoperative day (POD) 3 and at last follow-up.

Results: Overall, 347 patients with SIB 0-1 entered the study. A RF drop ≥25% was observed in 178 (37%) patients in POD 3 and in 91 (18.9%) patients at a median follow-up of 36 months, respectively. At multivariable analysis, age at surgery and PADUA score were significant predictive factors of clinically significant RF loss at POD 3, while age at surgery, female gender, higher BMI, Charlson Comorbidity Index (CCI) and preoperative eGFR were significant predictors of RF loss at last follow-up.

Conclusions: Age at surgery and higher PADUA score are significant predictors of early postoperative RF loss after ERASE for T1 renal tumors, while age at surgery, female gender, higher BMI, CCI and baseline RF significantly affect mid-term RF. Larger studies and a longer follow-up are needed to confirm these results.