Comparison of Perioperative Outcomes of Robotic Versus Laparoscopic Partial Nephrectomy for Complex Renal Tumors (RENAL Nephrometry Score of 7 or Higher)

PURPOSE To compare the perioperative outcomes of laparoscopic partial nephrectomy (LPN) and robotic partial nephrectomy (RPN) for moderately or highly complex tumors (RENAL nephrometry score ≥ 7). MATERIALS AND METHODS A retrospective analysis was performed for 127 consecutive patients who underwent either LPN (n=38) or RPN (n=89) between 2007 and 2013. Perioperative outcomes were compared. RESULTS There were no significant differences between the two groups with respect to patient gender, laterality, RENAL nephrometry score, or body mass index. The RPN group had a slightly higher RENAL nephrometry score (7.8 vs. 7.5, p=0.061) and larger tumor size (3.0 cm vs. 2.5 cm, p=0.044) but had a lower Charlson comorbidity index (3.7 vs. 4.4, p=0.017) than did the LPN group. There were no significant differences with respect to warm ischemia time, estimated blood loss, intraoperative complications, or operative time. Only one patient who underwent LPN had a positive surgical margin. There were statistically significant differences in surgical marginal width between the LPN and RPN groups (0.6 cm vs. 0.4 cm, p=0.001). No significant differences in postoperative complications were found between the two groups. Owing to potential baseline differences between the two groups, we performed a propensity-based matching analysis, in which differences in surgical margin width between the LPN and RPN groups remained statistically significant (0.6 cm vs. 0.4 cm, p=0.029). CONCLUSIONS RPN provides perioperative outcomes comparable to those of LPN and has the advantage of healthy parenchymal preservation for complex renal tumors (RENAL score ≥ 7).