The Learning Curve for Robot-assisted Partial Nephrectomy: Impact of Surgical Experience on Perioperative Outcomes

Comparing robotic and open partial nephrectomy under the prism of surgical precision: a meta-analysis of the average blood loss rate as a novel variable

Exploration of surgical precision in robotic procedures is extensive, yet lacks a unified framework for comparability. This study examines tissue handling precision by comparing the per-minute blood loss rate between robotic and open partial nephrectomy. A literature search from August 2022 to June 2024 identified 43 relevant studies providing data on estimated blood loss and procedure duration. The expected values and standard errors of these variables were used to compute the per-minute blood loss rate (Q). Meta-analytical methods estimated pooled and subgroup-level mean differences, favoring robotic surgery (MDQ = - 1.043 ml/min, CI95% = [- 1.338; - 0.747]). Subgroup analyses by publication year, patient matching, referral center count, and ROBINS-I status consistently supported this advantage. Sensitivity analyses confirmed the above benefit in studies with increased accuracy in reported results (MDQ = - 0.957 ml/min, CI95% = [- 1.269; - 0.646]), low risk of bias involving matched comparisons (MDQ = - 0.563 ml/min, CI95% = [- 0.716; - 0.410]), large sample sizes and increased statistical power (MDQ = - 0.780 ml/min, CI95% = [- 1.134; - 0.425]), and multicenter analyses with patient matching (MDQ = - 0.481 ml/min, CI95% = [- 0.698; - 0.263]). The subsequent analysis of correlation between the original variables suggested a slight reduction in the robotic advantage when the latter were proportionally related. Multilevel meta-regression at both temporal and qualitative scales consistently indicated a comparative benefit of the robotic approach. Potentially, lower per-minute blood loss compared to open surgery suggests that robotic partial nephrectomy demonstrates enhanced precision in tissue handling.

Preoperative risk calculator for the probability of completing nephron sparing for kidney cancer

PURPOSE

In absence of predictive models, preoperative estimation of the probability of completing partial (PN) relative to radical nephrectomy (RN) is invariably inaccurate and subjective. We aimed to develop an evidence-based model to assess objectively the probability of PN completion based on patients' characteristics, tumor's complexity, urologist expertise and surgical approach.

DESIGN, SETTING AND PARTICIPANTS

675 patients treated with PN or RN for cT1-2 cN0 cM0 renal mass by seven surgeons at one single experienced centre from 2000 to 2019.

OUTCOMES MEASUREMENTS AND STATISTICAL ANALYSES

The outcome of the study was PN completion. We used a multivariable logistic regression (MVA) model to investigate predictors of PN completion. We used SPARE score to assess tumor complexity. We used a bootstrap validation to compute the model's predictive accuracy. We investigated the relationship between the outcomes and specific predictors of interest such as tumor's complexity, approach and experience.

RESULTS

Of 675 patients, 360 (53%) were treated with PN vs. 315 (47%) with RN. Smaller tumors [Odds ratio (OR): 0.52, 95%CI 0.44-0.61; P < 0.001], lower SPARE score (OR: 0.67, 95%CI 0.47-0.94; P = 0.02), more experienced surgeons (OR: 1.01, 95%CI 1.00-1.02; P < 0.01), robotic (OR: 10; P < 0.001) and open (OR: 36; P < 0.001) compared to laparoscopic approach resulted associated with higher probability of PN completion. Predictive accuracy of the model was 0.94 (95% CI 0.93-0.95).

CONCLUSIONS

The probability of PN completion can be preoperatively assessed, with optimal accuracy relaying on routinely available clinical information. The proposed model might be useful in preoperative decision-making, patient consensus, or during preoperative counselling.

PATIENT SUMMARY

In patients with a renal mass the probability of completing a partial nephrectomy varies considerably and without a predictive model is invariably inaccurate and subjective. In this study we build-up a risk calculator based on easily available preoperative variables that can predict with optimal accuracy the probability of not removing the entire kidney.

Minimising warm ischaemia time during robot-assisted partial nephrectomy. A video-based assessment of tumour excision, kidney reconstruction and intermediate time

INTRODUCTION

Surgical video review is an emerging tool for assessing patient outcomes, especially in complex surgeries such as robot-assisted partial nephrectomy (RAPN). Assessing and measuring warm ischaemia time (WIT) during RAPN by dividing it into the time used for tumour excision time (ExcT), time used for kidney reconstruction time (RecT) and intermediate time (IntT) has not been performed before. This study aimed to analyse the factors that can influence all surgical times and assess their impact on positive surgical margins (PSMs) and complication rates.

METHODS

We evaluated 32 surgical video recordings from patients undergoing RAPN and measured WIT, ExcT, RecT and IntT with a stopwatch. Factors such as tumour characteristics and surgeon experience were also recorded. SPSS software was used to identify the predictors for all surgical times and to correlate ExcT with PSM and RecT with complication rate.

RESULTS

We recorded a median WIT of 1,048 s (17 min and 28 s). The median of ExcT, RecT and IntT was 398 s (37.1% of WIT), 518 s (46.7% of WIT) and 180 s (16.2% of WIT), respectively. We found a significant correlation (P < 0.001) between R.E.N.A.L. score and all surgical times. No correlation was found between ExcT and PSM (P = 0.488) and between RecT and the probability of developing complications (P = 0.544).

CONCLUSION

Tumour morphology influences all surgical times, and surgeon experience influences only ExcT. We observed a short RecT during RAPN though at the cost of increased ExcT, and we believe that improving surgical experience, especially for the excision of more complex tumours, can reduce WIT during RAPN.

Robot-assisted partial nephrectomy using the novel Hugo™ RAS system: Feasibility, setting and perioperative outcomes of the first off-clamp series

INTRODUCTION

Hugo Robot-Assisted Surgery (RAS) System has been conceived with enhanced modularity but its role for nephron-sparing surgery setting still remains poorly explored. We aimed to describe our experience in robot-assisted partial nephrectomy (RAPN) with a three-arms setting for the first off-clamp series using the new Hugo RAS System.

METHODS

Patients were placed on an extended flank position at the margin of the surgical bed with a slightly flexion (45°). The first 11 mm robotic trocar (camera port) was placed along the pararectal line 14 ± 2 cm far from the umbilicus. The pneumoperitoneum was then induced through the AirSeal system (SurgiQuest, Milford, Connecticut, USA©). Two more 8 mm operative robotic ports were placed under direct vision, either 8 ± 1 cm far from optic's port. Two 12 mm laparoscopic ports for bed-assistant were placed between robotic ports. Monopolar curved shears, fenestrated grasper, and large needle driver were used in a three-instruments configuration.

RESULTS

Off-clamp RAPN was successfully performed in seven patients with cT1 renal masses using a trans-peritoneal route. Median port placement and docking time was 6 min (IQR, 4-8 min). Hemostasis was achieved through renorraphy using a single transfix stitch with sliding clips technique. There was no need for additional ports placement. No intraoperative complications occurred, no clashing of robotic instruments or between the robotic arms was observed. No technical failures of the system occurred. Median console time was 83 min (IQR, 68-115 min). Median estimated blood loss were 200 ml (IQR, 50-400 ml). All patients were discharged between post-operative day 2 and 3, without the need of hospital readmission. No complications were recorded within the first 30 post-operative days.

CONCLUSIONS

We performed the first series of off-clamp RAPN using the novel HUGO RAS System. This novel robotic platform showed an easy-friendly docking system, providing excellent perioperative outcomes with a simple three-arms configuration.

Skill Transfer from Laparoscopic Partial Nephrectomy to the Hugo™ RAS System: A Novel Proficiency Score to Assess Surgical Quality during the Learning Curve

Background/Objectives: The absence of validated tools to assess the skill transfer from laparoscopy to robotic surgery remains an unsolved issue in the context of robot-assisted partial nephrectomy (RAPN). We aimed to describe and validate a novel proficiency score to critically evaluate the surgical quality of RAPN with the Hugo™ RAS System (Medtronic, Minneapolis, MN, USA). Methods: Between October 2022 and September 2023, 27 consecutive patients underwent off-clamp RAPN for localized renal tumors at our institution. To analyze the learning curve (LC), the cohort was chronologically divided into two phases of 6 months each. Proficiency was defined as the achievement of trifecta while maintaining a comparable intraoperative time in the interquartile range of laparoscopic partial nephrectomy performed by the same surgeon. A logistic binary regression model was built to identify predictors of proficiency achievement. Results: A proficiency score was achieved in 14 patients (74.1%). At univariable analysis, number of consecutive procedures > 12 (OR 13.7; 95%CI 2.05-21.1, p = 0.007), pathological tumor size (OR 0.92; 95%CI 0.89-0.99, p = 0.04) and essential blood hypertension (OR 0.16; 95%CI 0.03-0.82, p = 0.02) were found to be predictors of proficiency score. At multivariable analysis, after adjusting for potential confounding factors, number of consecutive procedures > 12 (OR 8.1; 95%CI 1.44-14.6, p = 0.03) was the only independent predictor of proficiency score achievement. Conclusions: Our results showed that the skills of an experienced laparoscopic surgeon are transferrable to the novel Hugo™ RAS System in the context of nephron-sparing surgery. Improved surgical quality may be expected after completing the first 12 consecutive procedures.

Open versus robotic partial nephrectomy in obese patients: a multi-institutional propensity score-matched analysis (UroCCR 43-Robese study)

INTRODUCTION

There is limited evidence on the outcomes of robotic partial nephrectomy (RPN) and open partial nephrectomy (OPN) in obese patients (BMI ≥ 30 kg/m2). In this study, we aimed to compare perioperative and oncological outcomes of RPN and OPN.

METHODS

We relied on data from patients who underwent PN from 2009 to 2017 at 16 departments of urology participating in the UroCCR network, which were collected prospectively. In an effort to adjust for potential confounders, a propensity-score matching was performed. Perioperative outcomes were compared between OPN and RPN patients. Disease-free survival (DFS) and overall survival (OS) were estimated using the Kaplan-Meier method and compared using the log-rank test.

RESULTS

Overall, 1277 obese patients (932 robotic and 345 open were included. After propensity score matching, 166 OPN and 166 RPN individuals were considered for the study purposes; no statistically significant difference among baseline demographic or tumor-specific characteristics was present. A higher overall complication rate and major complications rate were recorded in the OPN group (37 vs. 25%, p = 0.01 and 21 vs. 10%, p = 0.007; respectively). The length of stay was also significantly longer in the OPN group, before and after propensity-score matching (p < 0.001). There were no significant differences in Warm ischemia time (p = 0.66), absolute change in eGFR (p = 0.45) and positive surgical margins (p = 0.12). At a median postoperative follow-up period of 24 (8-40) months, DFS and OS were similar in the two groups (all p > 0.05).

CONCLUSIONS

In this study, RPN was associated with better perioperative outcomes (improvement of major complications rate and LOS) than OPN. The oncological outcomes were found to be similar between the two approaches.

Ablative Treatments for Small Renal Masses and Management of Recurrences: A Comprehensive Review

This review focuses on ablative techniques for small renal masses (SRMs), including radiofrequency ablation (RFA), cryoablation (CA), microwave ablation (MWA), and irreversible electroporation (IRE), and discusses recurrence management. Through an extensive literature review, we outline the procedures, outcomes, and follow-up strategies associated with each ablative method. The review provides a detailed examination of these techniques-RFA, CA, MWA, and IRE-elucidating their respective outcomes. Recurrence rates vary among them, with RFA and CA showing comparable rates, MWA demonstrating favorable short-term results, and IRE exhibiting promise in experimental stages. For managing recurrences, various strategies are considered, including active surveillance, re-ablation, or salvage surgery. Surveillance is preferred post-RFA and post-CA, due to slow SRM growth, while re-ablation, particularly with RFA and CA, is deemed feasible without additional complications. Salvage surgery emerges as a viable option for larger or resistant tumors. While ablative techniques offer short-term results comparable to surgery, further research is essential to understand their long-term effects fully. Decisions concerning recurrence management should consider individual and tumor-specific factors. Imaging, notably contrast-enhanced ultrasounds, plays a pivotal role in assessing treatment success, emphasizing the necessity of a multidisciplinary approach for optimal outcomes. The lack of randomized trials highlights the need for further research.

Gasless robot-assisted transaxillary hemithyroidectomy (RATH): learning curve and complications

PURPOSE

Gasless robot-assisted transaxillary hemithyroidectomy (RATH) is regarded as an alternative surgical option for thyroid operations. However, the associated steep learning curve is a clinical concern. This study evaluated the learning curve of RATH for surgeons without experience of endoscopic surgery and the early surgical outcomes of RATH.

METHODS

We conducted a retrospective study of patients who underwent gasless RATH and conventional hemithyroidectomy (CH) at Sun Yat-sen University Cancer Center, Guangzhou, China, from June 2021 to August 2022. The learning curve and early surgical outcomes of gasless RATH were evaluated. And the early surgical outcomes of gasless RATH were compared to CH.

RESULTS

In total, 105 patients who underwent gasless RATH and 104 patients who underwent CH were matched and assessed. The cumulative sum techniques (CUSUM) analysis showed that the peak point of gasless RATH operative time occurred at the 31st case. No clear single peak was identified in the CUSUM plot for drainage amount and blood loss. No significant difference in perioperative complications was observed between these two groups. Moreover, the number of postoperative patients who got sense of thyroid area traction were fewer in the gasless RATH group (n = 11, 10.5%) than in the CH group (n = 32, 30.8%).

CONCLUSION

Gasless RATH can be considered as an alternative approach to the conventional open procedure, as it is an easy remote access technique, with shorter learning curves and certain advantage such as less sense of thyroid area traction.

Hospital learning curves for robot-assisted surgeries: a population-based analysis

BACKGROUND

Robot-assisted surgery has been rapidly adopted. It is important to define the learning curve to inform credentialling requirements, training programs, identify fast and slow learners, and protect patients. This study aimed to characterize the hospital learning curve for common robot-assisted procedures.

STUDY DESIGN

This cohort study, using administrative health data for Ontario, Canada, included adult patients who underwent a robot-assisted radical prostatectomy (RARP), total robotic hysterectomy (TRH), robot-assisted partial nephrectomy (RAPN), or robotic portal lobectomy using four arms (RPL-4) between 2010 and 2021. The association between cumulative hospital volume of a robot-assisted procedure and major complications was evaluated using multivariable logistic models adjusted for patient characteristics and clustering at the hospital level.

RESULTS

A total of 6814 patients were included, with 5230, 543, 465, and 576 patients in the RARP, TRH, RAPN, and RPL-4 cohorts, respectively. There was no association between cumulative hospital volume and major complications. Visual inspection of learning curves demonstrated a transient worsening of outcomes followed by subsequent improvements with experience. Operative time decreased for all procedures with increasing volume and reached plateaus after approximately 300 RARPs, 75 TRHs, and 150 RPL-4s. The odds of a prolonged length of stay decreased with increasing volume for patients undergoing a RARP (OR 0.87; 95% CI 0.82-0.92) or RPL-4 (OR 0.77; 95% CI 0.68-0.87).

CONCLUSION

Hospitals may adopt robot-assisted surgery without significantly increasing the risk of major complications for patients early in the learning curve and with an expectation of increasing efficiency.

Biophotonics-Intraoperative Guidance During Partial Nephrectomy: A Systematic Review and Meta-analysis

CONTEXT

Partial nephrectomy (PN) with intraoperative guidance by biophotonics has the potential to improve surgical outcomes due to higher precision. However, its value remains unclear since high-level evidence is lacking.

OBJECTIVE

To provide a comprehensive analysis of biophotonic techniques used for intraoperative real-time assistance during PN.

EVIDENCE ACQUISITION

We performed a comprehensive database search based on the PICO criteria, including studies published before October 2022. Two independent reviewers screened the titles and abstracts followed by full-text screening of eligible studies. For a quantitative analysis, a meta-analysis was conducted.

EVIDENCE SYNTHESIS

In total, 35 studies were identified for the qualitative analysis, including 27 studies on near-infrared fluorescence (NIRF) imaging using indocyanine green, four studies on hyperspectral imaging, two studies on folate-targeted molecular imaging, and one study each on optical coherence tomography and 5-aminolevulinic acid. The meta-analysis investigated seven studies on selective arterial clamping using NIRF. There was a significantly shorter warm ischemia time in the NIRF-PN group (mean difference [MD]: -2.9; 95% confidence interval [CI]: -5.6, -0.1; p = 0.04). No differences were noted regarding transfusions (odds ratio [OR]: 0.5; 95% CI: 0.2, 1.7; p = 0.27), positive surgical margins (OR: 0.7; 95% CI: 0.2, 2.0; p = 0.46), or major complications (OR: 0.4; 95% CI: 0.1, 1.2; p = 0.08). In the NIRF-PN group, functional results were favorable at short-term follow-up (MD of glomerular filtration rate decline: 7.6; 95% CI: 4.6, 10.5; p < 0.01), but leveled off at long-term follow-up (MD: 7.0; 95% CI: -2.8, 16.9; p = 0.16). Remarkably, these findings were not confirmed by the included randomized controlled trial.

CONCLUSIONS

Biophotonics comprises a heterogeneous group of imaging modalities that serve intraoperative decision-making and guidance. Implementation into clinical practice and cost effectiveness are the limitations that should be addressed by future research.

PATIENT SUMMARY

We reviewed the application of biophotonics during partial removal of the kidney in patients with kidney cancer. Our results suggest that these techniques support the surgeon in successfully performing the challenging steps of the procedure.

Single-port vs multi-port robot-assisted partial nephrectomy: A single center propensity score-matched analysis

INTRODUCTION AND OBJECTIVES

The aim of the study is to compare key outcomes of Single-Port (SP) and Multi-Port (MP) robot-assisted partial nephrectomy (RAPN).

METHODS

A retrospective analysis was conducted on our prospectively collected database of patients who underwent SP-RAPN or MP-RAPN at our institution from January 2021 to August 2023. To adjust for potential baseline pre-operative confounders, a 1:1 propensity-score matching analysis (PSMa) was performed. The primary endpoint was to compare perioperative outcomes between the two groups. The secondary endpoint was to compare the achievement of the "Trifecta" outcome (defined as negative surgical margins, absence of high-grade complications and change in eGFR values (ΔeGFR) < 10% at 6 months follow-up) in the matched cohort.

RESULTS

After PSMa, 30 SP cases were matched 1:1 to 30 MP cases. In the matched cohort, there were no significant differences between SP and MP approaches in operative time, estimated blood loss, ischemia time, transfusions rate, intraoperative complications, postoperative complications, and positive surgical margin rates. Patients who underwent SP-RAPN had a shorter median length of stay [25 (IQR:24.0-34.5) vs 34 (IQR:30.2-48.0) hours, p < 0.003]. The Trifecta outcome was achieved in 16 (57%) of SP patients and 17 (63%) of MP patients (p = 0.8).

CONCLUSIONS

SP-RAPN can be safely implemented in a Center with an established MP-RAPN program. Despite being early in the SP-RAPN experience, key surgical outcomes are not compromised. While offering comparable perioperative and short-term functional outcomes, SP-RAPN can translate into faster recovery and shorter LOS, paving the way for outpatient robotic surgery.

Validation of a 3D-printed robot-assisted partial nephrectomy training model

Objectives

Most renal tumours can be treated with a partial nephrectomy, with robot-assisted partial nephrectomy becoming the new gold standard. This procedure is challenging to learn in a live setting, especially the enucleation and renorraphy phases. In this study, we attempted to evaluate face, content, and preliminary construct validity of a 3D-printed silicone renal tumour model in robotic training for robot-assisted partial nephrectomy.

Materials and Methods

We compared the operative results of three groups of surgeons with different experience levels (>20 partial nephrectomies, 1-20 partial nephrectomies and no experience at all) performing a robotic tumour excision of a newly developed silicone model with four embedded 3D-printed renal tumours. We evaluated the participants' performance using surgical margins, excision time, total preserved parenchyma, tumour injury and GEARS score (as assessed by two blinded experts) for construct validity. Postoperatively, the participants were asked to complete a survey to evaluate the usefulness, realism and difficulty of the model as a training and/or evaluation model. NASA-TLX scores were used to evaluate the operative workload.

Results

Thirty-six participants were recruited, each group consisting of 10-14 participants. The operative performance was significantly better in the expert group as compared to the beginner group. NASA-TLX scores proved the model to be of an acceptable difficulty level.Expert group survey results showed an average score of 6.3/10 on realism of the model, 8.2/10 on the usefulness as training model and 6.9/10 score on the usefulness as an evaluation tool. GEARS scores showed a non-significant tendency to improve between trials, emphasizing its potential as a training model.

Conclusion

Face and content validity of our 3D renal tumour model were demonstrated. The vast majority of participants found the model realistic and useful for training and for evaluation. To evaluate construct and predictive validity, we require further research, aiming to compare the results of 3D-model trained surgeons with those of untrained surgeons in real-life surgery.

Transition From Open and Laparoscopic to Robotic Partial Nephrectomy: Learning Curve and Outcomes

Introduction Partial nephrectomy (PN) is the current standard of care for patients with T1 renal tumors, and there has been a shift from an open and laparoscopic to a robot-assisted approach. The definition of the learning curve for robot-assisted PN (RAPN) is unclear, and various studies have identified warm ischemia time (WIT), perioperative complications, and surgical margins as the defining parameters for the assessment of improvement in these outcomes over time. The objective of this study was to evaluate the learning curve of a newly trained urologist for RAPN when comparing both open and laparoscopic approaches. Methods This study included 52 patients who underwent PN by open, laparoscopic, and robotic methods performed by a single, newly trained urologist over a period of seven years. Basic demographic and perioperative data were collected, and the learning curve was compared between the three approaches. Results Baseline parameters were similar for open (n = 15), laparoscopic (n = 12), and robotic (n = 25) PN except for tumor size and nephrometry score, which were higher in the open group (p = 0.000). Operative time was significantly longer in the robotic approach (180 minutes; p = 0.05), and blood loss was greater in the open group (450 mL; p = 0.000). Median WIT was 25 minutes; significant complications (Clavien Dindo ≥II) and positive surgical margins were 12% and 0%, respectively, in the robotic arm. Preoperative imaging and final histopathology data showed larger tumors being operated on, preferably by an open method, than laparoscopic and robotic PN (6.3 cm vs. 3.4 cm; p = 0.000). More open and laparoscopic procedures (n = 12, 10) were performed during the initial 26 cases, with a later transition to robot-assisted PN (n = 21) in the next 26 cases. None of the parameters showed improvement in the latter half, while operative time showed an increase (150 vs. 180 minutes; p = 0.045). Conclusion The learning curve becomes similar across three defined parameters, i.e., WIT, perioperative complications, and positive surgical margins, after performing a minimum of 25 RAPNs when compared to open and laparoscopic approaches. However, operative duration continues to improve and may take longer to become comparable. A newly trained urologist can safely perform RAPNs even with a small number of cases, especially those who have been previously trained for open and laparoscopic cases.

Impact of Assistant Experience on Perioperative Outcomes of Simple and Radical Laparoscopic Nephrectomy: Does It Really Matter?

Background and Objectives: While systematic reviews highlight the advantages of laparoscopic nephrectomy over traditional open surgery, the impact of an assistant's experience on surgical outcomes remains unclear. This study aims to evaluate whether the level of assistant expertise influences laparoscopic nephrectomy outcomes. Materials and Methods: Retrospective data from our institutional database were analyzed for patients who underwent laparoscopic nephrectomy between January 2018 and December 2022. Procedures were performed by a highly experienced surgeon, including postgraduate year (PGY)-3 to PGY-5 residents as assistants. Senior-level assistants had completed at least 10 procedures. Patient characteristics, surgical outcomes, and postoperative details were collected. Multivariable linear and logistic regression models were performed to test the effect of assistant experience (low vs. high) on estimated blood loss (EBL), length of stay (LOS), operative time (OT), and postoperative complications. Results: 105 patients were included, where 53% had highly experienced assistants and 47% had less experienced ones. Low assistant experience and higher BMI predicted longer operative time (OT), confirmed by multivariable regression (β = 40.5, confidence interval [CI] 18.7-62.3, p < 0.001). Assistant experience did not significantly affect EBL or LOS after adjusting for covariates (β = -14.2, CI -91.8-63.3, p = 0.7 and β = -0.83, CI -2.7-1.02, p = 0.4, respectively). There was no correlation between assistant experience and postoperative complications. Conclusions: Assistant experience does not significantly impact complications, EBL, and LOS in laparoscopic nephrectomy. Surgeries with less experienced assistants had longer OT, but the overall clinical impact seems limited. Trainee involvement remains safe, guided by experienced surgeons.

Patient-specific simulations and navigation systems for partial nephrectomy

Partial nephrectomy (PN) is the standard treatment for T1 renal cell carcinoma. PN is affected more by surgical variations and requires greater surgical experience than radical nephrectomy. Patient-specific simulations and navigation systems may help to reduce the surgical experience required for PN. Recent advances in three-dimensional (3D) virtual reality (VR) imaging and 3D printing technology have allowed accurate patient-specific simulations and navigation systems. We reviewed previous studies about patient-specific simulations and navigation systems for PN. Recently, image reconstruction technology has developed, and commercial software that converts two-dimensional images into 3D images has become available. Many urologists are now able to view 3DVR images when preparing for PN. Surgical simulations based on 3DVR images can change surgical plans and improve surgical outcomes, and are useful during patient consultations. Patient-specific simulators that are capable of simulating surgical procedures, the gold-standard form of patient-specific simulations, have also been reported. Besides VR, 3D printing is also useful for understanding patient-specific information. Some studies have reported simulation and navigation systems for PN based on solid 3D models. Patient-specific simulations are a form of preoperative preparation, whereas patient-specific navigation is used intraoperatively. Navigation-assisted PN procedures using 3DVR images have become increasingly common, especially in robotic surgery. Some studies found that these systems produced improvements in surgical outcomes. Once its accuracy has been confirmed, it is hoped that this technology will spread further and become more generalized.

Can the Abdominal Aortic Atherosclerotic Plaque Index Predict Functional Outcomes after Robot-Assisted Partial Nephrectomy?

This study aims to evaluate the abdominal aortic atherosclerotic plaque index (API)'s predictive role in patients with pre-operatively or post-operatively developed chronic kidney disease (CKD) treated with robot-assisted partial nephrectomy (RAPN) for renal cell carcinoma (RCC). One hundred and eighty-three patients (134 with no pre- and post-operative CKD (no CKD) and 49 with persistent or post-operative CKD development (post-op CKD)) who underwent RAPN between January 2019 and January 2022 were deemed eligible for the analysis. The API was calculated using dedicated software by assessing the ratio between the CT scan atherosclerotic plaque volume and the abdominal aortic volume. The ROC regression model demonstrated the influence of API on CKD development, with an increasing effect according to its value (coefficient 0.13; 95% CI 0.04-0.23; p = 0.006). The Model 1 multivariable analysis of the predictors of post-op CKD found that the following are independently associated with post-op CKD: Charlson Comorbidity Index (OR 1.31; p = 0.01), last follow-up (FU) Δ%eGFR (OR 0.95; p < 0.01), and API ≥ 10 (OR 25.4; p = 0.01). Model 2 showed API ≥ 10 as the only factor associated with CKD development (OR 25.2; p = 0.04). The median follow-up was 22 months. Our results demonstrate API to be a strong predictor of post-operative CKD, allowing the surgeon to tailor the best treatment for each patient, especially in those who might be at higher risk of CKD.

Cumulative sum analysis (CUSUM) for evaluating learning curve (LC) of robotic-assisted laparoscopic partial nephrectomy (RALPN)

Robotic-assisted laparoscopic partial nephrectomy (RALPN) is becoming a standard treatment for localized renal tumors worldwide. Data on the learning curve (LC) of RALPN are still insufficient. In the present study, we have attempted to gain further insight in this area by evaluating the LC using cumulative summation analysis (CUSUM). A series of 127 robotic partial nephrectomies were performed by two surgeons at our center between January 2018 and December 2020. CUSUM analysis was used to evaluate LC for operative time (OT). The different phases of surgical experience were compared in terms of perioperative parameters and pathologic outcomes. In addition, multivariate linear regression analysis was used to confirm the results of the CUSUM analysis by adjusting the phases of surgical experience for the other confounding factors that may affect OT. The median age of patients was 62 years, mean BMI was 28, and mean tumor size was 32 mm. Tumor complexity was classified as low, intermediate, and high risk according to the PADUA score in 44%, 38%, and 18%, respectively. The mean OT was 205 min, and trifecta was achieved in 72.4%. According to the CUSUM diagram, the LC of OT was divided into three phases: initial learning phase (18 cases), plateau phase (20 cases), and mastery phase (subsequent cases). The mean OT was 242, 208, and 190 min in the first, second, and third phases, respectively (P < 0.001). Surgeon experience phases were significantly associated with OT in multivariate analysis considering other preoperative and operative parameters. Surgical outcome was comparable between the three phases in terms of complications and achievement of trifecta; hospital stay was shorter in the mastery phase than in the first 2 phases (4 days vs 5 days, P = 0.02). The LC for RALPN is divided into 3 performance phases with CUSUM. Mastery of surgical technique was achieved after performing 38 cases. The initial learning phase of RALPN has no negative impact on surgical and oncologic outcomes .

Morbidity of elective surgery for localized renal masses among elderly patients: A contemporary multicenter study

BACKGROUND

The aging population and the incidence of renal cell carcinoma (RCC) are increasing worldwide. Over 25% of newly diagnosed LRM (localized renal masses) occur in patients over the eighth decade of life. The decision-making and treatment approach to LRM in this population represents a clinical dilemma due to inherited decreased functional reserve and competing mortality risks. Current literature reports conflicting evidence regarding age as a risk factor for worst surgical outcomes. As such, we aimed to evaluate the contemporary morbidity of elective surgery for LRM among elderly patients, focusing on intraoperative and postoperative complications.

METHODS

After Ethical Committee approval, we queried our prospectively maintained databases to identify patients with preoperative eGFR ≥60 ml/min/1.73 m [(David and Bloom, 2022) 22 and a normal contralateral kidney who underwent partial or radical nephrectomy (PN or RN) for a single cT1-T2N0M0 LRM between 1/2015-12/2021 at four high-volume European Academic Institutions. Patients were categorized by age groups: <50 yrs (young) vs. 50-75 (middle-aged) yrs vs.> 75 yrs (elderly). Postoperative complications were recorded according to Clavien-Dindo (CD) classification. The primary objectives were the proportion of patients experiencing intraoperative (IOC), any grade (AGC), and high-grade postoperative complications (HGC), defined as CD grade 3-5.

RESULTS

Overall, 2469/3076 (80.2%) patients met the inclusion criteria. Of these, 363 (14.7%) were young, 1682 (68.1%) were middle-aged, and 424 (17.2%) were elderly. Compared to middle-aged and young patients, elderly patients had a higher median Charlson Comorbidity Index (6 vs. 4 vs. 0, p < 0.01) and a higher proportion of cT1 renal mass (87.6% vs. 93.0% vs. 93.6%, p < 0.01). No differences among the study groups were found regarding surgical approach (open vs. minimally-invasive) and type of surgery (PN vs. RN). We found that older patients experienced similar IOC (4.5% vs. 4.2% vs. 3.3%, p = 0.7) and AGC (23.1% vs. 20.0% vs. 21.5%, p = 0.4) compared to middle-aged and young patients, respectively. Similarly, there were no significant differences in HGC between the study cohorts (0.7% vs. 1.4% vs. 1.7%, p = 0.8). At multivariable analysis, open approach and PN significantly predicted the occurrence of AGCs, while only the open surgical approach was associated with the occurrence of HGCs.

CONCLUSION

In kidney cancer tertiary referral centers, the risk of IOC and postoperative HGC after PN or RN for localized renal masses (LRM) is low, despite a non-negligible risk of AGC, especially in elderly patients. Further efforts should focus on identifying multidisciplinary strategies to select patients most likely to benefit from surgery among elderly candidates with LRMs and decrease the morbidity of surgery in this specific setting.

Robot-Assisted Renal Surgery with the New Hugo Ras System: Trocar Placement and Docking Settings

The current literature relating to the novel HugoTM RAS System lacks consistent data concerning the bedside features of robot-assisted partial nephrectomy (RAPN). To describe the trocar placement and docking settings for RAPN with a three-arm configuration to streamline the procedure with HugoTM RAS, between October 2022 and April 2023, twenty-five consecutive off-clamp RAPNs for renal tumors with the HugoTM RAS System were performed. We conceived a trouble-free three-arm setting to ease and standardize RAPN trocar placement and docking settings with HugoTM RAS. Perioperative data were collected. Post-operative complications were reported according to the Clavien-Dindo classification. The eGFR was calculated according to the CKD-EPI formula. Continuous variables were presented as the median and IQR, while frequencies were reported as categorical variables. Off-clamp RAPNs were successfully performed in all cases without the need for conversion or additional port placement. The median age and BMI were 69 years (IQR, 60-73) and 27.3 kg/m2 (IQR, 25.7-28.1), respectively. The median tumor size and R.E.N.A.L. score were 32.5 mm (IQR, 26-43.7) and 6 (IQR, 5-7), respectively. Two patients were affected by cT2 renal tumors. The median docking and console time were 5 (IQR, 5-6) and 90 min (IQR, 68-135.75 min), respectively, with slightly progressive improvements in the docking time achieved. No intraoperative complications occurred alongside clashes between instruments or with the bed assistant. In experienced hands, this simplified three-instrument configuration of the HugoTM RAS System for off-clamp RAPN resulted in feasible and safe practice, providing patient-tailored trocar placement and docking with non-inferior peri-perioperative outcomes to other robotic platforms.

The Surgical Learning Curve for Biochemical Recurrence After Robot-assisted Radical Prostatectomy

BACKGROUND

Improved cancer control with increasing surgical experience-the learning curve-was demonstrated for open and laparoscopic prostatectomy. In a prior single-center study, we found that this might not be the case for robot-assisted radical prostatectomy (RARP).

OBJECTIVE

To investigate the relationship between prior experience of a surgeon and biochemical recurrence (BCR) after RARP.

DESIGN, SETTING, AND PARTICIPANTS

We retrospectively analyzed the data of 8101 patients with prostate cancer treated with RARP by 46 surgeons at nine institutions between 2003 and 2021. Surgical experience was coded as the total number of robotic prostatectomies performed by the surgeon before the patient operation.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We evaluated the relationship of prior surgeon experience with the probability of BCR adjusting for preoperative prostate-specific antigen, pathologic stage, grade, lymph-node involvement, and year of surgery.

RESULTS AND LIMITATIONS

Overall, 1047 patients had BCR. The median follow-up for patients without BCR was 33 mo (interquartile range: 14, 61). After adjusting for case mix, the relationship between surgical experience and the risk of BCR after surgery was not statistically significant (p = 0.2). The 5-yr BCR-free survival rates for a patient treated by a surgeon with prior 10, 250, and 1000 procedures performed were, respectively, 82.0%, 82.7%, and 84.8% (absolute difference between 10 and 1000 prior procedures: 1.6% [95% confidence interval: 0.4%, 3.3%). Results were robust to a number of sensitivity analyses.

CONCLUSIONS

These findings suggest that, as opposed to open and laparoscopic radical prostatectomy, surgeons performing RARP achieve adequate cancer control in the early phase of their career. Further research should explore why the learning curve for robotic surgery differs from prior findings for open and laparoscopic radical prostatectomy. We hypothesize that surgical education, including simulation training and the adoption of objective performance metrics, is an important mechanism for flattening the learning curve.

PATIENT SUMMARY

We investigated the relationship between biochemical recurrence after robot-assisted radical prostatectomy and surgeon's experience. Surgeons at an early stage of their career had similar outcomes to those of more experienced surgeons, and we hypothesized that surgical education in robotics might be an important determinant of such a finding.

Robot-assisted partial nephrectomy for complex renal tumors: Analysis of a large multi-institutional database

INTRODUCTION

Highly complex renal masses pose a challenge to urologic surgeons' ability to perform robotic partial nephrectomy (RPN). Given the increased utilization of the robotic approach for small renal masses, we sought to characterize the outcomes and determine the safety and feasibility of RPN for complex renal masses from our large multi-institutional cohort.

METHODS

We performed a retrospective analysis of patients with R.E.N.A.L. Nephrometry Scores ≥10 who underwent RPN in our multi-institutional cohort (N = 372). Baseline demographic, clinical and tumor related characteristics were evaluated with the primary endpoint of trifecta achievement (defined as negative surgical margin, no major complications, and warm ischemia time ≤25 min). Relationships between variables were assessed using the chi-square test of independence, Fisher exact test, Mann-Whitney U test, and Kruskal Wallis test. Logistic regression was used to evaluate the relationship between baseline characteristics and trifecta achievement.

RESULTS

Of 372 patients in the study, mean age was 58 years, and median BMI was 30.49 kg/m². The median tumor size was 4.3 cm (3.0-5.9 cm). Most of the patients had R.E.N.A.L. scores of 10 (n = 253; 67.01%). Overall, trifecta was achieved in 72.04% of patients. Stratifying intraoperative and postoperative outcomes by R.E.N.A.L. scores, there was no significant difference in trifecta achievement, operative time, warm ischemia time (WIT), open conversion, major complication, or positive margin rates. Length of hospital stay was significantly longer for higher R.E.N.A.L. scores (median days 2 vs. 1, P = 0.012). Multivariate analyses for factors associated with trifecta achievement concluded that age and baseline eGFR were independently associated with trifecta achievement.

CONCLUSION

RPN is a safe and reproducible procedure for complex tumors with R.E.N.A.L. Nephrometry scores ≥10. Our results suggest excellent rates of trifecta achievement and short-term functional outcomes when performed by experienced surgeons. Long-term oncological and functional evaluation are needed to further support this conclusion.

The Learning Curve for Radical Nephrectomy for Kidney Cancer: Implications for Surgical Training

Although radical nephrectomy (RN) is the most common treatment for kidney cancer, no data on the learning curve for RN are available. In this study we investigated the effect of surgical experience (EXP) on RN outcomes using data for 1184 patients treated with RN for a cT1-3a cN0 cM0 renal mass. EXP was defined as the total number of RNs performed by each surgeon before the patient's operation. The primary study outcomes were all-cause mortality, clinical progression, Clavien-Dindo grade ≥2 postoperative complications (CD ≥2), and the estimated glomerular filtration rate (eGFR). Secondary outcomes were operative time, estimated blood loss, and length of stay. Multivariable analyses adjusted for case mix revealed no evidence of association between EXP and all-cause mortality (p = 0.7), clinical progression (p = 0.2), CD ≥2 (p = 0.6), or 12-mo eGFR (p = 0.9). Conversely, EXP was associated with shorter operative time (estimate -0.9; p < 0.01). Mortality, cancer control, morbidity, and renal function might not be affected by EXP. The very large cohort examined and the extensive follow-up support the validity of these negative findings.

Patient summary

For patients with kidney cancer undergoing surgical removal of a kidney, those treated by novice surgeons have similar clinical outcomes to those treated by experienced surgeons. Thus, this procedure represents a convenient scenario for surgical training if longer operating theatre time can be planned.

The State of Robotic Partial Nephrectomy: Operative, Functional, and Oncological Outcomes From A Robust Multi-Institution Collaborative

OBJECTIVE

To describe the most recent surgical, functional, and oncological outcomes of RPN utilizing one of the largest, prospectively maintained, multi-institution consortium of patients undergoing robotic renal surgery.

MATERIALS AND METHODS

Data was obtained from a prospectively maintained multi-institutional database of patients who underwent RPN for clinically localized kidney cancer between 2018 and 2022 by 9 high-volume surgeons. Demographic and tumor characteristics as well as operative, functional, and oncological outcomes were queried.

RESULTS

A total of 2836 patients underwent RPN. Intraoperative, postoperative, and 30-day major complication rates were 2.68%, 11.39%, and 3.24%, respectively. Median tumor size was 3.0 cm. Tumors with low complexity had a shorter median operative time, lower median EBL, shorter median ischemia time, lower postoperative complication rate, and lower decline in renal function There was no significant difference between tumor complexities with respect to the rate of conversion to radical nephrectomy, conversion to open, major complications, and positive margins. Lower BMI, smaller clinical tumor size, lower tumor complexity, and higher baseline eGFR were significantly associated with trifecta achievement.

CONCLUSION

Patient BMI, baseline eGFR, and tumor characteristics such as size and complexity are the most important predictors of trifecta achievement. Patients with complex tumors should be counseled that they are at increased risk of complications and worsening renal function after robotic partial nephrectomy.

The IRON Study: Investigation of Robot-assisted Versus Open Nephron-sparing Surgery

Background

Current literature does not provide large-scale data regarding clinical outcomes of robot-assisted (RAPN) versus open (OPN) partial nephrectomy. Moreover, data assessing predictors of long-term oncologic outcomes after RAPN are scarce.

Objective

To compare perioperative, functional, and oncologic outcomes of RAPN versus OPN, and to investigate the predictors of oncologic outcomes after RAPN.

Design setting and participants

This study included 3467 patients treated with OPN (n = 1063) or RAPN (n = 2404) for a single cT_1-2N₀M₀ renal mass from 2004 to 2018 at nine high-volume European, North American, and Asian institutions.

Outcome measurements and statistical analysis

The study outcomes were short-term postoperative, functional, and oncologic outcomes. Regression models investigated the effect of surgical approach (open vs Robot assisted) on study outcomes, and interaction tests were used for subgroup analyses. Propensity score matching for demographic and tumor characteristics was used in sensitivity analyses. Multivariable Cox-regression analyses identified predictors of oncologic outcomes after RAPN.

Results and limitations

Baseline characteristics were similar between patients receiving RAPN and OPN, with only few differences. After adjusting for confounding, RAPN was associated with lower odds of intraoperative (odds ratio [OR]: 0.39, 95% confidence interval [CI]: 0.22, 0.68) and Clavien-Dindo ≥2 postoperative (OR: 0.29, 95% CI: 0.16, 0.50) complications (both p < 0.05). This association was not affected by comorbidities, tumor dimension, PADUA score, or preoperative renal function (all p > 0.05 on interaction tests). On multivariable analyses, we found no differences between the two techniques with respect to functional and oncologic outcomes (all p > 0.05). Overall, there were 63 and 92 local recurrences and systemic progressions, respectively, with a median follow-up after surgery of 32 mo (interquartile range: 18, 60). Among patients receiving RAPN, we assessed predictors of local recurrence and systemic progression with discrimination accuracy (ie, C-index) that ranged from 0.73 to 0.81.

Conclusions

While cancer control and long-term renal function did not differ between RAPN and OPN, we found that the intra- and postoperative morbidity-especially in terms of complications-was lower after RAPN than after OPN. Our predictive models allow surgeons to estimate the risk of adverse oncologic outcomes after RAPN, with relevant implications for preoperative counseling and follow-up after surgery.

Patient summary

In this comparative study on robotic versus open partial nephrectomy, functional and oncologic outcomes were similar between the two techniques, with lower morbidity-especially in terms of complications-for robot-assisted surgery. The assessment of prognosticators for patients receiving robot-assisted partial nephrectomy may help in preoperative counseling and provides relevant data to tailor postoperative follow-up.

Evaluation of oncological outcomes of robotic partial nephrectomy according to the type of hilar control approach (On-clamp vs Off-clamp), a multicentric study of the French network of research on kidney cancer-UROCCR 58-NCT03293563

PURPOSE

To compare off-clamp vs on-clamp robotic partial nephrectomy (RPN) for renal cell carcinoma (RCC) in terms of oncological outcomes, and to assess the impact of surgical experience (SE).

METHODS

We extracted data of a contemporary cohort of 1359 patients from the prospectively maintained database of the French national network of research on kidney cancer (UROCCR). The primary objective was to assess the positive surgical margin (PSM) rate. We also evaluated the oncological outcomes regardless of the surgical experience (SE) by dividing patients into three groups of SE as a secondary endpoints. SE was defined by the caseload of RPN per surgeon per year. For the continuous variables, we used Mann-Whitney and Student tests. We assessed survival analysis according to hilar control approach by Kaplan-Meier curves with log rank tests. A logistic regression multivariate analysis was used to evaluate the independent factors of PSM.

RESULTS

Outcomes of 224 off-clamp RPN for RCC were compared to 1135 on-clamp RPN. PSM rate was not statistically different, with 5.6% in the off-clamp group, and 11% in the on-clamp group (p = 0.1). When assessing survival analysis for overall survival (OS), local recurrence-free survival (LR), and metastasis-free survival (MFS) according to hilar clamping approach, there were no statistically significant differences between the two groups with p value log rank = 0.2, 0.8, 0.1, respectively. In multivariate analysis assessing SE, hilar control approach, hospital volume (HV), RENAL score, gender, Age, ECOG, EBL, BMI, and indication of NSS, age at surgery was associated with PSM (odds ratio [OR] 1.03 (95% CI 1.00-1.04), 0.02), whereas SE, HV, and type of hilar control approach were not predictive factors of PSM.

CONCLUSION

Hilar control approach seems to have no impact on PSM of RPN for RCC. Our findings were consistent with randomized trials.

3D-Image guided robotic-assisted partial nephrectomy: a multi-institutional propensity score-matched analysis (UroCCR study 51)

PURPOSE

Robot-assisted partial nephrectomy (RAPN) is a difficult procedure with risk of significant perioperative complications. The objective was to evaluate the impact of preoperative planning and intraoperative guidance with 3D model reconstructions on perioperative outcomes of RAPN.

METHODS

We conducted a retrospective analysis of all patients who underwent RAPN for kidney tumor by three high-volume expert surgeons from academic centers. Clinical data were collected prospectively after written consent into the French kidney cancer network database UroCCR (CNIL-DR 2013-206; NCT03293563). Our cohort was divided into two groups: 3D-Image guided RAPN group (3D-IGRAPN) and control group. A propensity score according to age, pre-operative renal function and RENAL tumor complexity score was used. Both surgical techniques were compared in terms of perioperative outcomes.

RESULTS

The initial study cohort included 230 3D-IGRAPN and 415 control RAPN. Before propensity-score matching, patients in the 3D-IGRAPN group had a larger tumor (4.3 cm vs. 3.5 cm, P < 0.001) and higher RENAL complexity score (9 vs. 8, P < 0.001). Following propensity-score matching, there were 157 patients in both groups. The rate of major complications was lower for patients in the 3D-IGRAPN group (3.8% vs. 9.5%, P = 0.04). The median percentage of eGFR variation recorded at first follow-up was lower in the 3D-IGRAPN group (- 5.6% vs. - 10.5%, P = 0.002). The trifecta achievement rate was higher in the 3D-IGRAPN group (55.7% vs. 45.1%; P = 0.005).

CONCLUSION

Three-dimensional kidney reconstructions use for pre-operative planning and intraoperative surgical guidance lowers the risk of complications and improve perioperative clinical outcomes of RAPN.

A survey of augmented reality methods to guide minimally invasive partial nephrectomy

INTRODUCTION

Minimally invasive partial nephrectomy (MIPN) has become the standard of care for localized kidney tumors over the past decade. The characteristics of each tumor, in particular its size and relationship with the excretory tract and vessels, allow one to judge its complexity and to attempt predicting the risk of complications. The recent development of virtual 3D model reconstruction and computer vision has opened the way to image-guided surgery and augmented reality (AR).

OBJECTIVE

Our objective was to perform a systematic review to list and describe the different AR techniques proposed to support PN.

MATERIALS AND METHODS

The systematic review of the literature was performed on 12/04/22, using the keywords "nephrectomy" and "augmented reality" on Embase and Medline. Articles were considered if they reported surgical outcomes when using AR with virtual image overlay on real vision, during ex vivo or in vivo MIPN. We classified them according to the registration technique they use.

RESULTS

We found 16 articles describing an AR technique during MIPN procedures that met the eligibility criteria. A moderate to high risk of bias was recorded for all the studies. We classified registration methods into three main families, of which the most promising one seems to be surface-based registration.

CONCLUSION

Despite promising results, there do not exist studies showing an improvement in clinical outcomes using AR. The ideal AR technique is probably yet to be established, as several designs are still being actively explored. More clinical data will be required to establish the potential contribution of this technology to MIPN.

Objective assessment of intraoperative skills for robot-assisted partial nephrectomy (RAPN)

RAPN training usually takes place in-vivo and methods vary across countries/institutions. No common system exists to objectively assess trainee capacity to perform RAPN at predetermined performance levels prior to in-vivo practice. The identification of objective performance metrics for RAPN training is a crucial starting point to improve training and surgical outcomes. The authors sought to examine the reliability, construct and discriminative validity of objective intraoperative performance metrics which best characterize the optimal and suboptimal performance of a reference approach for training novice RAPN surgeons. Seven Novice and 9 Experienced RAPN surgeons video recorded one or two independently performed RAPN procedures in the human. The videos were anonymized and two experienced urology surgeons were trained to reliably score RAPN performance, using previously developed metrics. The assessors were blinded to the performing surgeon, hospital and surgeon group. They independently scored surgeon RAPN performance. Novice and Experienced group performance scores were compared for procedure steps completed and errors made. Each group was divided at the median for Total Errors score, and subgroup scores (i.e., Novice HiErrs and LoErrs, Experienced HiErrs and LoErrs) were compared. The mean inter-rater reliability (IRR) for scoring was 0.95 (range 0.84-1). Compared with Novices, Experienced RAPN surgeons made 69% fewer procedural Total Errors. This difference was accentuated when the LoErr Expert RAPN surgeon's performance was compared with the HiErrs Novice RAPN surgeon's performance with an observed 170% fewer Total Errors. GEARS showed poor reliability (Mean IRR = 0.44; range 0.0-0.8), for scoring RAPN surgical performance. The RAPN procedure metrics reliably distinguish Novice and Experienced surgeon performances. They further differentiated performance levels within a group with similar experiences. Reliable and valid metrics will underpin quality-assured novice RAPN surgical training.

Organ curvature sensing using pneumatically attachable flexible rails in robotic-assisted laparoscopic surgery

In robotic-assisted partial nephrectomy, surgeons remove a part of a kidney often due to the presence of a mass. A drop-in ultrasound probe paired to a surgical robot is deployed to execute multiple swipes over the kidney surface to localise the mass and define the margins of resection. This sub-task is challenging and must be performed by a highly-skilled surgeon. Automating this sub-task may reduce cognitive load for the surgeon and improve patient outcomes. The eventual goal of this work is to autonomously move the ultrasound probe on the surface of the kidney taking advantage of the use of the Pneumatically Attachable Flexible (PAF) rail system, a soft robotic device used for organ scanning and repositioning. First, we integrate a shape-sensing optical fibre into the PAF rail system to evaluate the curvature of target organs in robotic-assisted laparoscopic surgery. Then, we investigate the impact of the PAF rail's material stiffness on the curvature sensing accuracy, considering that soft targets are present in the surgical field. We found overall curvature sensing accuracy to be between 1.44% and 7.27% over the range of curvatures present in adult kidneys. Finally, we use shape sensing to plan the trajectory of the da Vinci surgical robot paired with a drop-in ultrasound probe and autonomously generate an Ultrasound scan of a kidney phantom.

Effect of augmented reality navigation technology on perioperative safety in partial nephrectomies: A meta-analysis and systematic review

Aim

To evaluate the impact of augmented reality surgical navigation (ARSN) technology on short-term outcomes of partial nephrectomy (PN).

Methods

A systematic literature search was conducted in PubMed, Embase, Cochrane, and Web of Science for eligible studies published through March 28, 2022. Two researchers independently performed the article screening, data extraction and quality review. Data analysis was performed using Cochrane Review Manager software.

Results

A total of 583 patients from eight studies were included in the analysis, with 313 in the ARSN-assisted PN group (AR group) and 270 in the conventional PN group (NAR group). ARSN-assisted PN showed better outcomes than conventional surgery in terms of operative time, estimated blood loss, global ischemia rate, warm ischemia time, and enucleation rate. However, there were no significant differences in the rate of Conversion to radical nephrectomy (RN), postoperative estimated glomerular filtration rate (eGFR), positive margin rate, and postoperative complication rate.

Conclusion

The utilization of ARSN can improve the perioperative safety of PN. Compared with conventional PN, ARSN-assisted PN can reduce intraoperative blood loss, shorten operative time, and improve renal ischemia. Although direct evidence is lacking, our results still suggest a potential advantage of ARSN in improving renal recovery after PN. However, as the ARSN system is still in an exploratory stage, its relevance in PN have been poorly reported. Additional high-quality randomized controlled trial (RCT) studies will be required to confirm the effect of ARSN on PN.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=301798, identifier PROSPERO ID: CRD42022301798.

The Intraoperative Complications Assessment and Reporting with Universal Standards (ICARUS) Global Surgical Collaboration Project: Development of Criteria for Reporting Adverse Events During Surgical Procedures and Evaluating Their Impact on the Postoperative Course

BACKGROUND

Intraoperative adverse events (iAEs) are surgical and anesthesiologic complications. Despite the availability of grading criteria, iAEs are infrequently reported in the surgical literature and in cases for which iAEs are reported, these events are described with significant heterogeneity.

OBJECTIVE

To develop Intraoperative Complications Assessment and Reporting with Universal Standards (ICARUS) Global Surgical Collaboration criteria to standardize the assessment, reporting, and grading of iAEs. The ultimate aim is to improve our understanding of the nature and frequency of iAEs and our ability to counsel patients regarding surgical procedures.

DESIGN, SETTING, AND PARTICIPANTS

The present study involved the following steps: (1) collecting criteria for assessing, reporting, and grading of iAEs via a comprehensive umbrella review; (2) collecting additional criteria via a survey of a panel of experienced surgeons (first round of a modified Delphi survey); (3) creating a comprehensive list of reporting criteria; (4) combining criteria acquired in the first two steps; and (5) establishing a consensus on clinical and quality assessment utility as determined in the second round of the Delphi survey.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Panel inter-rater agreement and consistency were assessed as the overall percentage agreement and Cronbach's α.

RESULTS AND LIMITATIONS

The umbrella review led to nine common criteria for assessing, grading, and reporting iAEs, and review of iAE grading systems led to two additional criteria. In the first Delphi round, 35 surgeons responded and two criteria were added. In the second Delphi round, 13 common criteria met the threshold for final guideline inclusion. All 13 criteria achieved the consensus minimum of 70%, with agreement on the usefulness of the criteria for clinical and quality improvement ranging from 74% to 100%. The mean inter-rater agreement was 89.0% for clinical improvement and 88.6% for quality improvement.

CONCLUSIONS

The ICARUS Global Collaboration criteria might aid in identifying important criteria when reporting iAEs, which will support all those involved in patient care and scientific publishing.

PATIENT SUMMARY

We consulted a panel of experienced surgeons to develop a set of guidelines for academic surgeons to follow when publishing surgical studies. The surgeon panel proposed a list of 13 criteria that may improve global understanding of complications during specific procedures and thus improve the ability to counsel patients on surgical risk.

Positive surgical margin's impact on short-term oncological prognosis after robot-assisted partial nephrectomy (MARGINS study: UroCCR no 96)

The oncological impact of positive surgical margins (PSM) after robot-assisted partial nephrectomy (RAPN) is still under debate. We compared PSM and Negative Surgical Margins (NSM) in terms of recurrence-free survival (RFS), metastasis-free survival (MFS) and overall survival (OS) after RAPN, and we identified predictive factors of PSM. Multi-institutional study using the UroCCR database, which prospectively included 2166 RAPN between April 2010 and February 2021 (CNIL DR 2013-206; NCT03293563). Two groups were retrospectively compared: PSM versus NSM. Prognostic factors were assessed using Kaplan-Meyer curves with log-Rank test, cox hazard proportional risk model and logistic regression after univariate comparison. 136 patients had PSM (6.3%) and 2030 (93.7%) had NSM. During a median follow-up of 19 (9-36) months after RAPN, 160 (7.4%) recurrences were reported. Kaplan-Meier curves and analysis suggested that RFS, MFS and OS were not affected by a PSM (p = 0.68; 0.71; 0.88, respectively). In multivariate analysis predictors of PSM were a lower RENAL score (p = 0.001), longer warm ischemia time (WIT) (p = 0.003) and Chromophobe Renal Cell Carcinoma (chrRCC) (p = 0.043). This study found no impact of PSM on RFS, MFS or OS, and predictors of PSM were the RENAL score, WIT and chrRCC.

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.

Roughness of the renal tumor surface could predict the surgical difficulty of robot-assisted partial nephrectomy

INTRODUCTION

Preoperative prediction of surgical difficulty of partial nephrectomy (PN) is essential to minimize the perioperative complications and to achieve a good surgical outcome. Recently, various scoring systems have been used to evaluate the difficulty of PN including R.E.N.A.L (Radius, Exophytic/Endophytic, Nearness, Anterior/Posterior, Location) nephrometry score. There were no scoring systems evaluating the roughness of the renal tumor surface and we hypothesized that the roughness of the renal tumor surface might affect the surgical difficulty of robot-assisted partial nephrectomy (RAPN). This study aimed to evaluate the impact of roughness of the renal tumor surface on the surgical outcome of RAPN.

METHODS

Overall, 161 patients underwent RAPN performed by the same surgeon between May 2016 and April 2019. We divided those tumors into two groups, like "roughness positive (tumor with roughness of tumor surface)" and "roughness negative (tumor without roughness of tumor surface)" according to the roughness of the endophytic region on preoperative computed tomography images. Clinical and pathological outcomes were compared between the two groups.

RESULTS

Eighty-five and 78 tumors were identified roughness negative and positive, respectively. Cases with roughness positive showed a significantly longer operative time, console time, and ischemia time and had greater blood loss than those with roughness negative. Significant and independent predictors of ischemia time and estimated glomerular filtration rate (eGFR) decrease were roughness of tumor surface, tumor size (not for eGFR decrease), and N score of the R.E.N.A.L nephrometry score.

CONCLUSION

Roughness of renal tumor surface was significantly and positively associated with ischemia time and the eGFR decrease rate.

The application of internal traction technique in retroperitoneal robot-assisted partial nephrectomy for renal ventral tumors

Background

For patients with prior intra-abdominal surgery or multiple arteries, the retroperitoneal robot-assisted partial nephrectomy (rRAPN) is a better choice. The renal ventral tumor poses an additional challenge due to poor tumor exposure. This study is determined to assess the feasibility of an internal traction technique (ITT) in rRAPN for the management of renal ventral tumors.

Methods

From November 2019 to March 2021, a total of 28 patients with renal ventral tumor underwent rRAPN. All patients had prior abdominal surgery or multiple arteries. The ITT group (20 patients), which improved the tumor exposure by traction of the kidney with suture, was compared with the traditional technique group (8 patients) in terms of warm ischemia time, estimated blood loss and postoperative hospital stay, retroperitoneal drainage, R.E.N.A.L. score, and serum creatinine. Differences were considered significant when P < 0.05.

Results

All rRAPN surgeries were successful without conversion to radical nephrectomy or open partial nephrectomy. The warm ischemia time was lower in the ITT group (17.10 min vs. 24.63 min; P < 0.05). Estimated blood loss in the traditional technique group was 324.88 ± 79.42 mL, and in the ITT group, it was 117.45±35.25 mL (P < 0.05). No significant differences with regard to postoperative hospital stay, retroperitoneal drainage, R.E.N.A.L. score, and serum creatinine were observed between both groups. Surgical margins were negative and no intraoperative complications occurred in all the patients. After 10 months of follow-up, no recurrence or metastasis occurred in all cases.

Conclusion

ITT is a feasible, safe, and valid procedure in rRAPN for renal ventral tumors. Application of ITT improved the exposure and reduces warm ischemic time in comparison with the conventional procedure.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02684-1.

Retroperitoneal Robot-assisted Partial Nephrectomy: A Systematic Review and Pooled Analysis of Comparative Outcomes

Context

Robot-assisted partial nephrectomy (RAPN) has gained increasing popularity as primary minimally invasive surgical treatment for localized renal tumors, and it has preferably been performed with a transperitoneal approach. However, the retroperitoneal approach represents an alternative approach given potential advantages.

Objective

To provide an updated analysis of the comparative outcomes of retroperitoneal RAPN (R-RAPN) versus transperitoneal RAPN (T-RAPN).

Evidence acquisition

A systematic review of the literature was performed up to September 2021 using MEDLINE, EMBASE, and Web of Science databases, according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) recommendations. A sensitivity analysis was performed considering only matched-pair studies.

Evidence synthesis

Seventeen studies, which were published between 2013 and 2021, were retrieved. None of them was a randomized clinical trial. Among the 6,266 patients included in the meta-analysis, 2261 (36.1%) and 4,005 (63.9%) underwent R-RAPN and T-RAPN, respectively. No significant difference was found in terms of baseline features. The T-RAPN group presented a higher rate of male patients (odds ratio [OR]: 0.86, p = 0.03) and larger tumor size (weighted mean difference [WMD]: 0.2 cm; p = 0.003). The R-RAPN group reported more frequent posterior renal masses (OR: 0.23; p < 0.0001). The retroperitoneal approach presented lower estimated blood loss (WMD: 30.41 ml; p = 0.001), shorter operative time (OT; WMD: 20.36 min; p = 0.0001), and shorter length of stay (LOS; WMD: 0.35 d; p = 0.002). Overall complication rates were 13.7% and 16.05% in the R-RAPN and T-RAPN groups, respectively (OR: 1.32; p = 0.008). There were no statistically significant differences between the two groups regarding major (Clavien-Dindo classification ≥3 grade) complication rate, “pentafecta” achievement, as well as positive margin rates. When considering only matched-pair studies, no difference between groups was found in terms of baseline characteristics. Posterior renal masses were more frequent in the R-RAPN group (OR: 0.6; p = 0.03). Similar to the analysis of the entire cohort, R-RAPN reported lower EBL (WMD: 35.56 ml; p < 0.0001) and a shorter OT (WMD: 18.31 min; p = 0.03). Overall and major complication rates were similar between the two groups. The LOS was significantly lower for R-RAPN (WMD: 0.46 d; p = 0.02). No statistically significant difference was found between groups in terms of overall PSM rates.

Conclusions

R-RAPN offers similar surgical outcomes to T-RAPN, and it carries potential advantages in terms of shorter OT and LOS. Available evidence remains limited by the lack of randomized clinical trials.

Patient summary

In this review of the literature, we looked at comparative outcomes of two surgical approaches to robot-assisted partial nephrectomy. We found that the retroperitoneal technique offers similar surgical outcomes to the transperitoneal one, with potential advantages in terms of shorter operative time and length of hospital stay.

Perioperative outcomes following robot-assisted partial nephrectomy for renal cell carcinoma according to surgeon generation

Objective

The experience of performing robot-assisted partial nephrectomy (RAPN) is associated with better surgical outcomes. However, surgeon’s generation may impact surgical outcomes. We evaluated the perioperative outcomes of RAPN between first- and second-generation surgeons according to the surgeon’s experience.

Methods

This study included 529 patients who underwent RAPN for renal cell carcinoma from January 2013 to November 2018. Four specific surgeons performed the surgery. According to the surgeon’s generation, the patients were divided into two groups: first-generation and second-generation. To reflect the learning curve of RAPN, the surgical outcomes of each case (1–50, 51–100, 101–150) were evaluated between these groups.

Results

Between 1 to 50 cases and 101–150 cases, no significant differences in patient characteristics were observed between the two generations. Between 51–100 cases, age at surgery was significantly younger in the first-generation than in the second-generation group (58 years vs. 64 years, p = 0.04). The second-generation group had a shorter operation time in cases 1–50 (169 min vs. 188 min, p = 0.0001), 51–100 (145 min vs. 169 min, p = 0.008), and 101–150 (142 min vs. 165 min, p = 0.009), than the first-generation group. Although shorter WIT and higher trifecta achievement were observed in the second-generation group than in the first-generation group between 1–50 cases, the difference was not noted between 51–100 cases and 101–150 cases.

Conclusion

Patients operated by second-generation surgeons had better surgical outcomes than first-generation surgeons, especially during the early experience period, which might result from their assistance experience, sophisticated surgical procedures refined by the first-generation, and the first-generation surgeon’s introduction.

A particle filter approach to dynamic kidney pose estimation in robotic surgical exposure

PURPOSE

Traditional soft tissue registration methods require direct intraoperative visualization of a significant portion of the target anatomy in order to produce acceptable surface alignment. Image guidance is therefore generally not available during the robotic exposure of structures like the kidneys which are not immediately visualized upon entry into the abdomen. This paper proposes guiding surgical exposure with an iterative state estimator that assimilates small visual cues into an a priori anatomical model as exposure progresses, thereby evolving pose estimates for the occluded structures of interest.

METHODS

Intraoperative surface observations of a right kidney are simulated using endoscope tracking and preoperative tomography from a representative robotic partial nephrectomy case. Clinically relevant random perturbations of the true kidney pose are corrected using this sequence of observations in a particle filter framework to estimate an optimal similarity transform for fitting a patient-specific kidney model at each step. The temporal response of registration error is compared against that of serial rigid coherent point drift (CPD) in both static and simulated dynamic surgical fields, and for varying levels of observation persistence.

RESULTS

In the static case, both particle filtering and persistent CPD achieved sub-5 mm accuracy, with CPD processing observations 75% faster. Particle filtering outperformed CPD in the dynamic case under equivalent computation times due to the former requiring only minimal persistence.

CONCLUSION

This proof-of-concept simulation study suggests that Bayesian state estimation may provide a viable pathway to image guidance for surgical exposure in the abdomen, especially in the presence of dynamic intraoperative tissue displacement and deformation.

Factors affecting the learning curve in robotic colorectal surgery

Learning related to robotic colorectal surgery can be measured by surgical process (such as time or adequacy of resection) or patient outcome (such as morbidity or quality of life). Time based metrics are the most commonly used variables to assess the learning curve because of ease of analysis. With analysis of the learning curve, there are factors which need to be considered because they may have a direct impact on operative times or may be surrogate markers of clinical effectiveness (unrelated to times). Variables which may impact on operation time include surgery case mix, hybrid technique, laparoscopic and open colorectal surgery experience, robotic surgical simulator training, technology, operating room team, and case complexity. Multidimensional analysis can address multiple indicators of surgical performance and include variables such as conversion rate, complications, oncological outcome and functional outcome. Analysis of patient outcome and/or global assessment of robotic skills may be the most reliable methods to assess the learning curve.

External Validation of a Novel Comprehensive Trifecta System in Predicting Oncologic and Functional Outcomes of Partial Nephrectomy: Results of a Multicentric Series

Background: To validate a novel trifecta for evaluating outcomes of partial nephrectomy (PN) on a multicentric dataset. Methods: Between 2007 and 2020, three renal cancer databases were queried for patients with solitary renal masses who underwent PN (n = 649). Trifecta was estimated for overall cohort and contributing centers. Overall survival (OS), cancer-specific survival (CSS) and end-stage renal disease (ESRD) probabilities were assessed by Kaplan–Meier. Cox regression was used to identify predictors of OS, CSS, ESRD. For all analyses, a p < 0.05 was considered significant. Results: At a median follow-up of 22.7 months (IQR 12.5–76.5) overall trifecta was 76.7% [Centre A; (n = 230; 68.6%), B (n = 68; 77.3%), C (n = 200; 88.4%); p = 0.001). On Kaplan–Meier, patients achieving trifecta exhibited higher OS (p = 0.024), higher CSS (p = 0.015) and lower ESRD rates (p = 0.024). On multivariable analysis, age (HR 1.04; 95% CI 1.01–1.08) and trifecta (HR 0.34; 95% CI 0.15–0.76) were independent predictors of OS while pT stage (HR 1.95; 95% CI 0.45–8.43) and trifecta (HR 0.33; 95% CI 0.16–0.67) were predictors of CSS (each p < 0.01). Preoperative CKD stage ≥ 3a (HR 13.1; 95% CI 4.07–42.6) and trifecta (HR 0.41; 95% CI 0.19–0.87) were independent predictors of ESRD (each p < 0.05). Conclusions: On external validation, trifecta was an independent predictor of all PN endpoints, regardless of hilar control and ischemia duration.

The impact of a fellow on a regional robotic-assisted partial nephrectomy service

INTRODUCTION

Training a fellow has a cost in time and effort for the surgeon and their team. Their relative inexperience may also negatively affect the patient. The aim of this study was to determine and quantify the impact of a fellow on a regional robotic-assisted partial nephrectomy service and on perioperative outcomes.

MATERIALS AND METHODS

We reviewed the prospectively collected data for 522 patients who had undergone robotic-assisted partial nephrectomy since 2015 during the tenure of six fellows. Perioperative outcomes for three groups were compared: group A (no fellow participation), group B (some participation) and group C (fellow completed entire operation). We also reviewed progression over 12 months.

RESULTS

Demographics were similar in all groups apart from the percentage of men, which was lower in group C (p < 0.05). Operative time was 27 minutes longer for group B (p < 0.001). Warm ischaemia time was significantly shorter for group A but the difference was only four minutes (p < 0.001). Length of stay was slightly shorter for group C compared with the other groups (p < 0.01). Trifecta achievement was greatest for group A (p < 0.001). There were no perioperative deaths in any group and positive margins, complications and readmissions were low and similar in all groups. Towards the end of their fellowship, fellows performed more operations independently.

CONCLUSION

There is a measurable, but small, negative impact of a fellow on a robotic-assisted partial nephrectomy service, which reduces with experience. With appropriate supervision and patient selection, a fellow can be taught robotic-assisted partial nephrectomy without affecting patient safety or treatment outcome.

Development and Validation of an Objective Scoring Tool for Robot-Assisted Partial Nephrectomy: Scoring for Partial Nephrectomy

Objective: To develop a structured and objective scoring tool for assessment of robot-assisted partial nephrectomy (RAPN): Scoring for Partial Nephrectomy (SPaN). Materials and Methods: Content development: RAPN was deconstructed into 6 domains by a multi-institutional panel of 10 expert robotic surgeons. Performance on each domain was represented on a Likert scale of 1 to 5, with specific descriptions of anchors 1, 3, and 5. Content validation: The Delphi methodology was utilized to achieve consensus about the description of each anchor for each domain in terms of appropriateness of the skill assessed, objectiveness, clarity, and unambiguous wording. The content validity index (CVI) of ≥0.75 was set as cutoff for consensus. Reliability: 15 de-identified videos of RAPN were utilized to determine the inter-rater reliability using linearly weighted percent agreement, and Construct validation of SPaN was described in terms of median scores and odds ratios. Results: The expert panel reached consensus (CVI ≥0.75) after 2 rounds. Consensus was achieved for 36 (67%) statements in the first round and 18 (33%) after the second round. The final six-domain SPaN included Exposure of the kidney; Identification and dissection of the ureter and gonadal vessels; Dissection of the hilum; Tumor localization and exposure; Clamping and tumor resection; and Renorrhaphy. The linearly weighted percent agreement was >0.75 for all domains. There was no difference between median scores for any domain between attendings and trainees. Conclusion: Despite the lack of significant construct validity, SPaN is a structured, reliable, and procedure-specific tool that can objectively assesses technical proficiency for RAPN.