Robot assisted partial nephrectomy versus laparoscopic partial nephrectomy for renal tumors: a multi-institutional analysis of perioperative outcomes.

Purpose: Robot assisted partial nephrectomy is rapidly emerging as an alternative to laparoscopic partial nephrectomy for the treatment of renal malignancy. We present the largest multi-institution comparison of the 2 approaches to date, describing outcomes from 3 experienced minimally invasive surgeons.

Materials And Methods: We performed a retrospective chart review, evaluating 118 consecutive laparoscopic partial nephrectomies and 129 consecutive robot assisted partial nephrectomies performed between 2004 and 2008 by 3 experienced minimally invasive surgeons at 3 academic centers. Perioperative data were recorded along with clinical and pathological outcomes.

Results: The robot assisted and laparoscopic partial nephrectomy groups were equivalent in terms of age, gender, body mass index, American Society of Anesthesiologists classification (2.3 vs 2.4) and radiographic tumor size (2.9 vs 2.6 cm), respectively. Comparison of operative data revealed no significant differences in terms of overall operative time (189 vs 174 minutes), collecting system entry (47% vs 54%), pathological tumor size (2.8 vs 2.5 cm) and positive margin rate (3.9% vs 1%) for robot assisted and laparoscopic partial nephrectomy, respectively. Intraoperative blood loss was less for robot assisted vs laparoscopic partial nephrectomy (155 vs 196 ml, p = 0.03) as was length of hospital stay (2.4 vs 2.7 days, p <0.0001). Warm ischemia times were significantly shorter in the robot assisted partial nephrectomy series (19.7 vs 28.4 minutes, p <0.0001). Subset analysis based on complexity revealed that tumor complexity had no effect on operative time or estimated blood loss for robot assisted partial nephrectomy, although complexity did affect these factors for laparoscopic partial nephrectomy. In addition, for simple and complex tumors robot assisted partial nephrectomy provided significantly shorter warm ischemic time than laparoscopic partial nephrectomy (15.3 vs 25.2 minutes for simple, p <0.0001; 25.9 vs 36.7 minutes for complex, p = 0.0002). There were no intraoperative complications during robot assisted partial nephrectomy vs 1 complication during laparoscopic partial nephrectomy. Postoperative complication rates were similar for robot assisted and laparoscopic partial nephrectomy (8.6% vs 10.2%).

Conclusions: Robot assisted partial nephrectomy is a safe and viable alternative to laparoscopic partial nephrectomy, providing equivalent early oncological outcomes and comparable morbidity to a traditional laparoscopic approach. Moreover robot assisted partial nephrectomy appears to offer the advantages of decreased hospital stay as well as significantly less intraoperative blood loss and shorter warm ischemia time, the latter of which may help to provide maximal preservation of renal reserve. In addition, operative parameters for robot assisted partial nephrectomy appear to be less affected by tumor complexity compared to laparoscopic partial nephrectomy. Interestingly while the advantages of robotic surgery have historically been believed to aid laparoscopic naïve surgeons, these data indicate that robot assisted partial nephrectomy may also benefit experienced laparoscopic surgeons.