Robot-assisted partial nephrectomy for cT1b-T2 renal tumors: Perioperative outcomes from a large multicentre international dataset (Vattikuti Global Quality Initiative on Robotic Urologic Surgery)

INTRODUCTION & OBJECTIVES: Robot-assisted partial nephrectomy (RAPN) has been shown to be an effective minimally invasive treatment for small renal tumors with similar perioperative results and decreased warm ischemia time (WIT) compared to conventional laparoscopic partial nephrectomy. The robotic technology has the potential to expand the indications of minimally invasive nephron-sparing surgery to more challenging renal lesions. However, the outcomes of RAPN for larger, cT1b-T2 renal tumors have been reported only in relatively small and mainly single-institutional experiences. MATERIAL & METHODS: 293 patients who underwent RAPN for a cT1b-T2 renal tumor between October 2006 and July 2013 were identified from a multi-institutional retrospective database including 1011 cases of RAPN from 9 tertiary robotic centres in Europe, North America, India and Australia. Intraoperative outcomes, pathological outcomes and complications were assessed. Complications were graded according to the Clavien-Dindo classification system. RESULTS: 264 RAPNs were performed for cT1b tumors (median size 48 mm, IQR 42-54) and 29 for cT2 tumors (median size 80 mm, IQR 72-94). Median age of patients was 58 years and the average Charlson comorbidity score was 2 (IQR 0-3). Median operative time was 210 minutes (IQR 158-256). Median estimated blood loss and WIT were 150 ml (IQR 100-300) and 20 minutes (IQR 16-24), respectively. Ten intraoperative complications occurred (3.4%). Postoperative complications were observed in 58 cases (19.8%) and 23 (8.6%) were Clavien grade ≥3. Hospital stay was on average 3 days (IQR 1-5). A benign pathology was found in 46 cases (16.1%). Fourteen tumors (4.8%) were pT3a at final pathology and positive surgical margins were detected in 11 cases (3.8%). CONCLUSIONS: RAPN for cT1b-T2 tumors is feasible with limited blood loss and acceptable WIT, complication and positive surgical margin rate in centres with advanced robotic expertise.