Perinephric Toxic Fat: Impact on Surgical Complexity, Perioperative Outcome, and Surgical Approach in Partial Nephrectomy.

INTRODUCTION: To assess influencing factors on perinephric toxic fat (high Mayo Adhesive Probability [MAP] score) and the impact of high MAP scores on surgical complexity, perioperative outcome, and surgical approach in patients with localized renal tumors undergoing open (OPN) and robot-assisted partial nephrectomy (RAPN). METHODS: 698 patients were included in this study. Based on preoperative imaging, adherent perinephric fat (APF) was assessed to define MAP scores. Regression analyses assessed influencing parameters for high MAP scores (≥3), predictors of surgical outcome, and influencing factors on surgical approach. RESULTS: OPN was performed in 331 (47%) patients, and 367 (53%) patients underwent RAPN. Male gender (p < 0.001), age ≥65 (p < 0.001), and BMI ≥27.4 kg/m2 (p < 0.001) showed to be significantly influencing factors for the presence of APF. High MAP scores showed to be an influencing factor for a prolonged surgery duration (OR = 1.68, 95% CI 1.22-2.31, p = 0.002) and a significant predictor to rather undergo OPN than RAPN (OR = 1.5, 95% CI 1.05-2.15, p = 0.027). CONCLUSION: Older, male patients with high BMI scores have a higher risk for APF. The presence of APF increases surgery time and may have an impact on decision making regarding the preferred surgical approach.

Impact of Surgical Experience Before Robot-assisted Partial Nephrectomy on Surgical Outcomes: A Multicenter Analysis of 2500 Patients.

Background: Robot-assisted partial nephrectomy (RAPN) is a challenging procedure that is influenced by a multitude of factors. Objective: To assess the impact of prior surgical experience on perioperative outcomes in RAPN. Design setting and participants: In this retrospective multicenter study, results for 2548 RAPNs performed by 25 surgeons at eight robotic referral centers were analyzed. Perioperative data for all consecutive RAPNs from the start of each individual surgeon's experience were collected, as well as the number of prior open or laparoscopic kidney surgeries, pelvic surgeries (open, laparoscopic, robotic), and other robotic interventions. Intervention: Transperitoneal or retroperitoneal RAPN. Outcome measurements and statistical analysis: The impact of prior surgical experience on operative time, warm ischemia time (WIT), major complications, and margin, ischemia, complication (MIC) score (negative surgical margins, WIT ≤20 min, no major complications) was assessed via univariate and multivariable regression analyses accounting for age, gender, body mass index (BMI), American Society of Anesthesiologists score, PADUA score, and RAPN experience. Results and limitations: BMI, PADUA score, and surgical experience in RAPN had a strong impact on perioperative outcomes. A plateau effect for the learning curve was not observed. Prior laparoscopic kidney surgery significantly reduced the operative time (p < 0.001) and WIT (p < 0.001) and improved the MIC rate (p = 0.022). A greater number of prior robotic pelvic interventions decreased WIT (p = 0.011) and the rate of major complications (p < 0.001) and increased the MIC rate (p = 0.011), while prior experience in open kidney surgery did not. One limitation is the short-term follow-up. Conclusions: Mastering of RAPN is an ongoing learning process. However, prior experience in laparoscopic kidney and robot-assisted pelvic surgery seems to improve perioperative outcomes for surgeons when starting with RAPN, while experience in open surgery might not be crucial. Patient summary: In this multicenter analysis, we found that a high degree of experience in keyhole kidney surgery and robot-assisted pelvic surgery helps surgeons in achieving good initial outcomes when starting robot-assisted kidney surgery.

Are there limits of robotic partial nephrectomy? TRIFECTA outcomes of open and robotic partial nephrectomy for completely endophytic renal tumors.

BACKGROUND: To compare the outcomes of robot-assisted (RAPN) and open partial nephrectomy (OPN) for completely endophytic renal tumors. METHODS: Consecutive patients undergoing OPN or RAPN for entirely endophytic tumors in four high-volume centers between 2008 and 2016 were identified. Endophytic masses were identified based on sectional imaging. Patient characteristics and surgical outcome were compared using Mann-Whitney-U-test and chi-squared-tests. Uni- and multivariate analyses were performed to identify predictors of TRIFECTA achievement and excisional volume loss. RESULTS: Out of 1128 patients, 10.9% (64) of RAPN and 13.9% (76) of OPN underwent surgery for entirely endophytic tumors. Operative time was longer for RAPN (169 vs 140 min, P = 0.03) while ischemia time was shorter (13 vs 18 min, P = 0.001). Complication rates were comparable (21% OPN vs 22% RAPN, P = 0.91) and TRIFECTA achievement was not different between the groups (68% OPN vs 75% RAPN, P = 0.39). In multivariate analyses type of surgery was not associated with TRIFECTA achievement or excisional volume loss. Here, only tumor complexity (OR 0.48, P = 0.001) and size (OR 1.01, P = 0.002) were independent predictors. CONCLUSION: For entirely endophytic tumors, both RAPN and OPN offer good TRIFECTA achievement. This encourages the use of NSS even for these highly complex tumors using the surgeon's preferred approach.