Robot-assisted partial nephrectomy of multiple tumors: a multicenter analysis

Abstract

BACKGROUND: Robot-assisted partial nephrectomy (RAPN) is increasingly performed in challenging tumor constellations like multiple renal masses. METHODS: The objective was to investigate influencing factors on postoperative renal function (PRF) after ipsilateral robot-assisted partial nephrectomy of multiple tumors (iRAPN-MT). In this retrospective multicenter study, perioperative data of 132 trans- or retroperitoneal iRAPN-MT for ≥ two tumors were analyzed focusing on influencing factors on PRF and acute kidney injury including RIFLE and trifecta criteria. The impact of patient-, surgery- and tumor-related factors was investigated via uni- and multivariate regression analyses. RESULTS: The majority of patients had two renal masses, with three or more lesions in 19%. Median operative time was 175 minutes. Eighty-five percent of the tumors were dissected on-clamp with a median cumulative warm ischemia time (WIT<inf>sum</inf>) of 15 minutes. Trifecta criteria were fulfilled in 57%. In regression analyses, WIT<inf>sum</inf>, BMI and preoperative eGFR had an impact on eGFR loss before discharge (median -11.6 mL/min). BMI and Charlson Comorbidity Index were independent predictors for the lowest RIFLE stage during hospitalization. CONCLUSIONS: iRAPN-MT for multiple ipsilateral renal masses is feasible with good trifecta rates. While mostly unmodifiable patient-associated parameters were independent predictors on PRF impairment, WIT<inf>sum</inf> was identified as a surgery-related independent parameter.