Postoperative outcomes of transperitoneal versus retroperitoneal robotic partial nephrectomy: a propensity-score matched comparison focused on patient mobilization, return to bowel function, and pain.

Literature meta-analyses comparing transperitoneal versus retroperitoneal approach to robotic partial nephrectomy (RPN) suggested some advantages favoring retroperitoneoscopy. Unfortunately, patient-centered data about mobilization, canalization, pain, and use of painkillers remained anecdotally reported. The present analysis aimed to compare transperitoneal versus retroperitoneal RPN focusing on such outcomes. Study data including baseline variables, perioperative, and postoperative outcomes of interest were retrieved from prospectively maintained institutional database (Jan 2018-May 2023) and compared between treatment groups (transperitoneal versus retroperitoneal). Propensity score matching was performed using the STATA command psmatch2 considering age, sex, body mass index, previous abdominal surgery, RENAL score, tumor size and location, and cT stage. The logit of propensity score was used for matching, with a 1:1 nearest neighbor algorithm, without replacement (caliper of 0.001). A total of 442 patients were included in the unmatched analysis: 330 underwent transperitoneal RPN 112 retroperitoneal RPN. After propensity score, 98 patients who underwent retroperitoneal RPN were matched with 98 patients who underwent transperitoneal RPN. Matched cohorts had comparable patients' demographics and tumor features. We found similarity between the two laparoscopic accesses in all outcomes but in blood loss, which favored retroperitoneoscopic RPN (median 150 (IQR 100-300) versus 100 (IQR 0-100) ml, p = 0.03). No differences were found in terms of time to mobilization with ambulation, return to complete bowel function, postoperative pain, but higher painkillers consumption was reported after transperitoneal RPN (p < 0.004). The present study compared the transperitoneal versus the retroperitoneal approach to RPN, confirming the similarity between the two approaches in all perioperative outcomes. Based on our findings, the choice of the surgical approach to RPN may remain something that the surgeon decides.