Trans-peritoneal vs. retroperitoneal robotic assisted partial nephrectomy in posterior renal tumours: need for a risk-stratified patient individualised approach. A systematic review and meta-analysis

A novel mini-retractor for retroperitoneal laparoscopic partial nephrectomy

BACKGROUND

Retroperitoneal partial nephrectomy (RLPN) is the premier treatment for localized renal tumors despite narrow operation space. Many efforts have been taken to facilitate the operation of RLPN, but the optimal resolution remains debatable.

OBJECTIVE

To explore the feasibility of using Mini-lap to improve workspace and surgical vision in RLPN.

DESIGN, SETTING, AND PARTICIPANTS

A multicenter retrospective review of 51 patients who underwent RLPN with Mini-lap from January 2018 to December 2020 was conducted.

SURGICAL PROCEDURE

Standard RLPN under three poles was performed in all cases. We highlighted the usage of Mini-lap (Teleflex Minilap percutaneous Surgical System) as a novel retractor in RLPN.

OUTCOME AND MEASUREMENTS AND STATICAL ANALYSIS

Demographics, preoperative, intraoperative, and postoperative outcomes were assessed.

RESULTS AND LIMITATIONS

All 51 cases completed RLPN with three ports successfully and no conversion to open surgery. The mean diameter of tumors was (3.53 ± 1.05) cm, in which 62.7% (32/51) were located anteriorly. The operation time and warm ischemic time (WIT) were (86.7 ± 15.9) min and (25.6 ± 5) min respectively. Minor complications (Clavien grade 1-2) occurred in 6 cases. The limitations were small sample size, retrospective design, and absence of control.

CONCLUSIONS

Mini-lap could be used as a mini-retractor in RLPN, sparing extra assistant ports, expanding workspace, and optimizing vision.

PATIENT SUMMARY

With highlights of larger workspace and less instrument interference, mini-lap could be applied in retroperitoneal laparoscopic partial nephrectomy.

Comparison of the perioperative outcomes of robot-assisted laparoscopic transperitoneal versus retraperitoneal partial nephrectomy for posterior-lateral renal tumors: a systematic review and meta-analysis

The study aims to assess the available literature and compare the perioperative outcomes of robotic-assisted partial nephrectomy (RAPN) for posterior-lateral renal tumors using transperitoneal (TP) and retroperitoneal (RP) approaches. Systematically searched the Embase, PubMed, and Cochrane Library databases for literature. Eligible studies were those that compared TP-RAPN and RP-RAPN for posterior-lateral renal tumors. The data from the included studies were analyzed and summarized using Review Manager 5.3, which involved comparing baseline patient and tumor characteristics, intraoperative and postoperative outcomes, and oncological outcomes. The analysis included five studies meeting the inclusion criteria, with a total of 1440 patients (814 undergoing RP-RAPN and 626 undergoing TP-RAPN). Both groups showed no significant differences in age, gender, BMI, R.E.N.A.L. score, and tumor size. Notably, compared to TP-RAPN, the RP-RAPN group demonstrated shorter operative time (OT) (MD: 17.25, P = 0.01), length of hospital stay (LOS) (MD: 0.37, P < 0.01), and lower estimated blood loss (EBL) (MD: 15.29, P < 0.01). However, no significant differences were found between the two groups in terms of warm ischemia time (WIT) (MD: -0.34, P = 0.69), overall complications (RR: 1.25, P = 0.09), major complications (the Clavien-Dindo classification ≥ 3) (RR: 0.97, P = 0.93), and positive surgical margin (PSM) (RR: 1.06, P = 0.87). The systematic review and meta-analysis suggests RP-RAPN may be more advantageous for posterior-lateral renal tumors in terms of OT, EBL, and LOS, but no significant differences were found in WIT, overall complications, major complications, and PSM. Both surgical approaches are safe, but a definitive advantage remains uncertain.

Robotic transperitoneal versus retroperitoneal approach for anterior renal mass nephron-sparing surgery

Robotic nephron-sparing surgery is traditionally performed via a transperitoneal (TP) approach. However, the retroperitoneal (RP) approach has gained popularity, particularly for posterolateral renal masses. The RP approach is associated with shorter operative time, less blood loss, and shorter length of stay, while preserving oncologic outcomes in selected masses. Here, we aim to assess the feasibility of the RP approach in excising anterior renal masses. Patients ≥ 18 years of age who underwent robotic nephron-sparing surgery for anterior renal masses were retrospectively identified (2008-2022). Baseline demographics, tumor characteristics, and perioperative data were collected and characterized based on TP vs RP approaches. Wilcoxon rank sum test and Pearson's Chi-squared test were used to compare continuous and categorical variables, respectively. Two hundred and sixteen patients were included-178 (82.4%) underwent TP approach and 38 (17.6%) underwent RP approach. Baseline demographics, preoperative tumor size, and renal nephrometry scores were similar. The RP approach was associated with shorter operative (150 vs 203 min, p < 0.001) and warm ischemia time (12 vs 21 min, p < 0.001), and less blood loss (20 vs 100 cc, p = 0.002) (Table 1). The RP approach was associated with shorter length of stay (1 vs 2 days, p < 0.001) and less total complications (5.3% vs 19.1%, p = 0.038). Major complication (Clavien-Dindo Grade > 3) rates were similar. There was no difference in positive surgical margin rates or pathologic characteristics. Robotic RP approach for nephron-sparing surgery is feasible for eligible anterior tumors and is associated with favorable perioperative outcomes with preserved negative surgical margin rates. Table 1 Patient baseline demographics Overall Transperitoneal Retroperitoneal p value Median/N IQR/% Median/N IQR/% Median/N IQR/% N 216 178 82.4% 38 17.6% Age (years) 60.5 (52.1-67.7) 60.4 (52.8-67.7) 61.6 (49.1-69.2) 0.393 Sex Male 126 58.3% 100 56.2% 26 68.4% Female 90 41.7% 78 43.8% 12 31.6% 0.165 Race White 162 75.0% 137 77.0% 25 65.8% Asian 4 1.9% 2 1.1% 2 5.3% Black 21 9.7% 18 10.1% 3 7.9% Hispanic 26 12.0% 18 10.1% 8 21.1% Other 2 0.9% 2 1.1% 0 0.0% 0.197 Body mass index (kg/m2)  < 25 32 14.8% 25 14.0% 7 18.4% 25-30 68 31.5% 55 30.9% 13 34.2% 30-35 60 27.8% 50 28.1% 10 26.3% 35 +  56 25.9% 48 27.0% 8 21.1% 0.808 Prior abdominal surgery Yes 118 54.6% 104 58.4% 14 36.8% No 98 45.4% 74 41.6% 24 63.2% 0.015 Prior kidney surgery Yes 10 4.6% 9 5.1% 1 2.6% No 206 95.4% 169 94.9% 37 97.4% 0.518 Chronic kidney disease stage ≥ 3 Yes 45 20.8% 38 21.3% 7 18.4% No 171 79.2% 140 78.7% 31 81.6% 0.687 Charlson comorbidity index 0 138 63.9% 116 65.2% 22 57.9% 1 46 21.3% 38 21.4% 8 21.1% 2 19 8.8% 13 7.3% 6 15.8%  ≥ 3 13 6.0% 11 6.2% 2 5.3% 0.412 Tumor size (cm) 2.7 (2-3.6) 2.8 (2-3.5) 2.55 (2-3.7) 0.796 Tumor laterality Left 100 46.3% 78 43.8% 22 57.9% Right 116 53.7% 100 56.2% 16 42.1% 0.114 Clinical T stage cT1a 186 86.1% 152 85.4% 34 89.5% cT1b 30 13.9% 26 14.6% 4 10.5% 0.509 RENAL Nephrometry score Low (4 to 6) 94 43.5% 76 42.7% 18 47.4% Intermediate (7 to 9) 112 51.9% 94 52.8% 18 47.4% High (≥ 10) 19 4.6% 8 4.5% 2 5.3% 0.829 TE tumor enucleation, SPN standard margin partial nephrectomy, IQR interquartile range.

Transperitoneal vs. Retroperitoneal Approach in Laparoscopic Partial Nephrectomy for Posterior Renal Tumors: A Retrospective, Multi-Center, Comparative Study

Purpose: The aim of our study is to compare the perioperative, functional, and oncological outcomes of laparoscopic transperitoneal partial nephrectomy (LTPN) and laparoscopic retroperitoneal partial nephrectomy (LRPN) for posterior cT1 renal tumors. Methods: We retrospectively collected data on all patients who consecutively underwent LTPN and LRPN for posterior cT1 renal tumors in three different centers from January 2015 to January 2023. Patients with a single, unilateral, cT1 renal mass, located in the posterior renal surface were included. Patients' data regarding perioperative, functional, and oncological outcomes were collected from medical records and statistically analyzed and compared. Results: A total of 128 patients was obtained, with 53 patients in the LPTN group and 75 patients in the LRPN group. Baseline characteristics were similar. Warm ischemia time (WIT) (18.8 vs. 22.6 min, p = 0.002) and immediate postoperative eGFR drop (-6.1 vs. -13.0 mL/min/1.73 m2, p = 0.047) were significantly lower in the LPTN group. Estimated blood loss (EBL) (100 vs. 150 mL, p = 0.043) was significantly lower in the LRPN group. All other perioperative and functional outcomes and complications were similar between the groups. The positive surgical margin (PSM) rate was lower in the LRPN group, although without statistical significance (7.2% vs. 13.5%, p = 0.258). Surgical success defined by Trifecta (WIT ≤ 25 min, no PSM, and no major postoperative complication) was similar between both approaches. Conclusions: LTPN has significantly shorter WIT and a significantly smaller drop in immediate eGFR when compared to LRPN for posterior renal tumors. On the other hand, LRPN has significantly less EBL than LTPN. LRPN demonstrated fewer PSMs than LTPN, albeit without statistical significance. In terms of overall surgical success, as defined by Trifecta, both approaches achieved similar results.

A comparison of perioperative outcomes of transperitoneal versus retroperitoneal robot-assisted partial nephrectomy: a systematic review

RAPN can be carried out via a transperitoneal or retroperitoneal approach. The choice between the two approaches is open to debate and usually based on surgeon preference. The perioperative outcomes of transperitoneal robot-assisted partial nephrectomy versus retroperitoneal robot-assisted partial nephrectomy were compared. A systematic review of the literature was performed up to May 2020, using PubMed, Cochrane, Scopus and Ovid databases. Articles were selected according to a search strategy based on PRISMA criteria. Only studies comparing TRAPN with RRAPN were eligible for inclusion. Eleven studies were included in the quantitative synthesis. Baseline demographics (age, BMI, ASA, tumour size, and RENAL nephrometry score), intraoperative data (operative time, estimated blood loss, and warm ischaemia time) and postoperative outcomes (major complications according to Clavien-Dindo, length of hospital stay (LOS) and positive surgical margin rate) were recorded. A total of 3139 patients were included (2052 TRAPN vs. 1087 RRAPN). There was no significant difference in demographic variables (age, BMI), tumour size (p = 0.06) nor the nephrometry score (p = 0.20) between the two groups. Operative time (p = 0.02), estimated blood loss (p < 0.00001) and LOS (p < 0.00001) were significantly lower in the RRAPN group. No differences were found in major postoperative complications (Clavien-Dindo > 3; p = 0.37), warm ischaemia time (p = 0.37) or positive surgical margins (p = 0.13). Future researchers must attempt to achieve adequately powered, expertise based, multi-surgeon and multi-centric studies comparing TRAPN and RRAPN. RRAPN gives similar outcomes to TRAPN. RRAPN is associated with reduced operative time and LOS. Ideally, surgeons should be familiar and competent in both RAPN approaches and adopt a risk-stratified and patient-centred individualised approach, dependent on the tumour and patient characteristics. RAPN is feasible via two approaches. The retroperitoneal approach seems to be associated with a shorter operation time and hospital stay.

Long term experience of robotic retroperitoneal partial nephrectomy as the default approach in the management of renal masses: should the paradigm shift?

Although retroperitoneal surgery has demonstrated a better quality of recovery compared to transperitoneal routes, Retroperitoneal Robot Assisted Partial Nephrectomy (RRAPN) remains proportionally infrequent. As the boundaries of what is achievable robotically continue to be pushed, we present our experience at a high-volume tertiary referral centre that specialises in retroperitoneal surgery, exploring its feasibility as standard of care in the management of small renal masses. A prospective database of 784 RAPNs (2009-2020) was reviewed and 721 RRAPNs (92%) were performed at our centre. In our practice, we utilise a four-port approach to RRAPN. Patient, tumour and operative characteristics were assessed and both oncological outcomes and trifecta and pentafecta achievements were determined. Pentafecta was defined as achieving trifecta (negative surgical margin, no post-operative complications and WIT of < 25 min) plus over 90% estimated GFR preservation and no CKD stage upgrading at 1 year. Multivariate analysis was conducted to predict peri-operative factors which may prevent achieving a trifecta/pentafecta outcome. From 784 cases, 112 RAPNs were performed for imperative reasons, whilst the remainder were elective. Mean BMI ± s.d amongst our cohort was 28.6 ± 5.7. Mean tumour size was 3.1 cm (range 0.8-10.5 cm) and 47% of cases were stratified as intermediate/high risk using R.E.N.A.L nephrometry scoring. Forty-six patients had lesions in a hilar location, and 31% were anterior. Median blood loss was 30mls, with an open conversion rate of 1% and transfusion rate of 1.6%. Median warm ischaemic time (WIT) was 21 min, positive surgical margins were found in 4% and our post-operative Clavien 3/ > complication rate was 2.6%. We had a 1-day median length of stay with a 30 day readmission rate of 2%. Of 631 patients (80%) with a definitive histological diagnosis of cancer, 23% had T1b/ > disease. Over a mean 15 month follow-up period (range 1-125 months), 2% of patients developed recurrences and our cohort demonstrated a 99% 5 year cancer specific survival. Trifecta was achieved in 67% of cases and pentafecta in 47%. Age (p = 0.05), operative time (p = 0.008), pT1b tumours (p = 0.03), R.E.N.A.L score and blood loss (p = 0.001) were found to statistically significantly influence achievement of trifecta. Pentafecta achievement was influenced by R.E.N.A.L score (p = 0.008), operative time (p = 0.001) and blood loss (p = 0.001). We demonstrate the retroperitoneal approach in RAPN is feasible and safe irrespective of lesion location and complexity. In the hands of high-volume centres that are skilled in the retroperitoneal approach the benefits of retroperitoneal surgery can be extended even to challenging cohorts of patients without compromising their oncological or functional outcomes.

Retroperitoneal vs. transperitoneal robotic partial nephrectomy: a multicenter propensity-score matching analysis (PADORA Study - UroCCR n° 68)

BACKGROUND

Robot-assisted partial nephrectomy can be performed through either a transperitoneal or retroperitoneal approach. This study aimed to compare the rate of trifecta achievement between retroperitoneal (RRPN) and transperitoneal (TRPN) robot-assisted partial nephrectomy using a large multicenter prospectively-maintained database and propensity-score matching analysis.

METHODS

This study was launched by the French Kidney Cancer Research Network, under the UroCCR Project (NCT03293563). Patients who underwent TRPN or RRPN by experienced surgeons in 15 participating centers were included. Data on demographic and clinical parameters, tumor characteristics, renal function, and surgical parameters were collected. The primary outcome was the rate of trifecta achievement, which was defined as a warm ischemia time of less than 25 minutes, negative surgical margins, and no major complications. Secondary outcomes included operative time, hospital length-of-stay, blood loss, postoperative complications, postoperative renal function, and each trifecta item taken alone. Subgroup analysis was done according to tumor location.

RESULTS

A total of 2879 patients (2581 TRPN vs. 298 RRPN) were included in the study. Before matching, trifecta was achieved in 73.0% of the patients in the TRPN group compared to 77.5% in the RRPN group (P=0.094). After matching 157 patients who underwent TRPN to 157 patients who underwent RRPN, the trifecta rate was 82.8% in the TRPN group vs. 84.0% in the RRPN group (P=0.065). The RRPN group showed shorter operative time (123 vs. 171 min; P<0.001) and less blood loss (161 vs. 293 mL; P<0.001). RRPN showed a higher trifecta achievement for posterior tumors than TRPN (71% vs. 81%; P=0.017).

CONCLUSIONS

RRPN is a viable alternative to the transperitoneal approach, particularly for posterior renal tumors, and is a safe and effective option for partial nephrectomy.

Comparison of Transperitoneal and Retroperitoneal Robotic Partial Nephrectomy for Patients with Completely Lower Pole Renal Tumors

(1) Background: For completely lower pole renal tumors, we compared the perioperative outcomes of robotic partial nephrectomy via transperitoneal and retroperitoneal approaches. (2) Methods: Complete lower pole renal tumors were defined as tumors that received 1 point for the “L” element of the R.E.N.A.L. and located at the lower pole of kidney. After confirming consistency in baseline characteristics, oncological and functional benefits were compared. Pentafecta achievement was used to represent the perioperative optimal outcome, followed by multivariate analysis of factors associated with the lack of pentafecta achievement. (3) Results: Among 151 patients identified, 116 (77%) underwent robotic partial nephrectomy via a transperitoneal approach and 35 (23%) via a retroperitoneal approach. Patients undergoing transperitoneal robotic partial nephrectomy experienced more blood loss than those undergoing retroperitoneal robotic partial nephrectomy (50 mL vs. 40 mL, p = 0.015). No significant differences were identified for operative time (120 min vs. 120 min), ischemia time (19 min vs. 20 min), positive surgical margins (0.0% vs. 2.86%), postoperative rate of complication (12.07% vs. 5.71%). No significant differences were identified in pathologic variables, eGFR decline in postoperative 12-month (3.9% vs. 5.4%) functional follow-up. Multivariate cox analysis showed that tumor size (OR: 0.523; 95% CI: 0.371−0.736; p < 0.001) alone was independently correlated to the achievement of pentafecta. (4) Conclusions: For completely lower pole renal tumors, transperitoneal and retroperitoneal robotic partial nephrectomy provide similar outcomes. These two surgical approaches remain feasible options for these cases.

Analyses of operative time according to procedure phases during robot-assisted laparoscopic partial nephrectomy using the iPhone application "My Intuitives"

PURPOSE

We investigated operative time according to procedure phases in robot-assisted laparoscopic partial nephrectomy (RAPN) and identify variables associated with longer operative time in each procedure phase.

METHODS

This retrospective, single-center study included 108 patients who underwent RAPN conducted by an experienced surgeon. Operative time was divided into dissection, resection, tumor bed suture, and renorrhaphy and hemostasis phases, which were derived from the iPhone application "My Intuitives." Multivariate analyses were performed to identify possible predictors such as sex, body mass index, tumor complexity, and surgical approach for longer operative time in each phase.

RESULTS

The median console time was 65 min, and median operative times in dissection, resection, tumor bed suture, and renorrhaphy and hemostasis phases were 41, 8, 9, and 8 min, respectively. In the multivariate analysis, longer console time was observed in high complexity tumors (vs. low, OR: 8.01, 95% CI: 1.94-33.0) and transperitoneal approach (vs. retroperitoneal approach, OR: 3.62, 95% CI: 1.94-33.0). High complexity tumors were significantly associated with longer operative time in all procedure phases, and the male sex was associated with a longer operative time in the dissection phase than the female sex (OR: 3.61, 95% CI: 1.18-11.0).

CONCLUSION

The identified significant predictive factors associated with longer operative time were the male sex and high complexity in the dissection phase, high complexity in the resection phase, in the tumor bed suture phase as well as in the renorrhaphy and hemostasis phase. These findings may help to predict the difficulty of performing RAPN in terms of operative time.

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.

[Robot-assisted surgery for renal cell carcinoma - today a standard?]

Twenty years have passed since the first reports on robot-assisted kidney tumor surgery in 2001. However, robotic surgery has not spread to all German urologic departments yet. Hence, one has to question whether robot-assisted kidney tumor surgery can be considered a standard today. Until now, no prospective randomized controlled trials have compared robot-assisted radical nephrectomy with the open or laparoscopic approach. Regardless, laparoscopy and robotics both have proven better perioperative and comparable oncological outcomes than with open nephrectomy. In direct comparison, robot-assisted nephrectomy has no additional benefits over the laparoscopic approach and is less cost-effective. However, reports on robot-assisted level III or IV vena cava tumor thrombectomies illustrate that robotic surgery can be superior to the laparoscopic approach in highly complex interventions. Likewise, no prospective randomized controlled trials have analyzed robot-assisted partial nephrectomy yet. When conducted by experienced surgeons, robotic and laparoscopic partial nephrectomies can also have lower morbidity compared to the open approach. No consensus has been reached when directly comparing robotic and laparoscopic partial nephrectomy. However, evidence is increasing that robot-assisted partial nephrectomy can offer additional benefits, especially for the treatment of highly complex endophytic renal tumors. Thereof, head-to-head comparisons are often impacted by patient- and tumor-related factors, as well as the learning curve of the surgeon, bed-side assistant and the annual caseload of the department. Hence, one has to conclude that robot-assisted kidney tumor surgery has evolved into a standard procedure with good results. The perioperative outcomes of robot-assisted surgery are superior to the open technique at a comparable oncological follow-up. Even if robot-assisted interventions are often more expensive than laparoscopic surgery due to higher costs of acquisition, robotics have the potential to gain superior results especially in very complex tumor surgery. Due to expiring patent protections, new manufacturers and the development of new technologies, the market of robotic surgery will most likely undergo significant changes and its costs will probably decrease within the next years.

Retroperitoneal versus transepritoneal robot-assisted partial nephrectomy for postero-lateral renal masses: an international multicenter analysis

PURPOSE

To assess the outcomes of retroperitoneal robot-assisted partial nephrectomy (r-RAPN) in a large cohort of patients with postero-lateral renal masses comparing to those of transperitoneal RAPN (t-RAPN).

METHODS

Patients with posterior (R.E.N.A.L. score grading P) or lateral (grading X) renal mass who underwent RAPN in six high-volume US and European centers were identified and stratified into two groups according to surgical approach: r-RAPN ("study group") and t-RAPN ("control group"). Baseline characteristics, intraoperative, and postoperative data were collected and compared.

RESULTS

Overall, 447 patients were identified for the analysis. 231 (51.7%) and 216 (48.3%) patients underwent r-RAPN and t-RAPN, respectively. Baseline characteristics were not statistically significantly different between the groups. r-RAPN group reported lower median operative time (140 vs. 170 min, p < 0.001). No difference was found in ischemia time, estimated blood loss, and intraoperative complications. Overall, 47 and 54 postoperative complications were observed in r-RAPN and t-RAPN groups, respectively (20.3 vs. 25.1%, p = 0.9). 1 and 2 patients reported major complications (Clavien-Dindo ≥ III grade) in the retroperitoneal and transperitoneal groups (0.4 vs. 0.9%, p = 0.9). There was no difference in hospital re-admission rate, median length of stay, and PSM rate. Trifecta criteria were achieved in 90.3 and 89.2% of r-RAPN and t-RAPN, respectively (p = 0.7).

CONCLUSION

r-RAPN and t-RAPN offer similar postoperative, functional, and oncological outcomes for patients with postero-lateral renal tumors. Our analysis suggests an advantage for r-RAPN in terms of shorter operative time, whereas it does not confirm a difference in terms of length of stay, as suggested by previous reports.

Retroperitoneal Robot-Assisted Partial Nephrectomy (rRAPN): Surgical Technique and Review

PURPOSE OF REVIEW

We aim to offer a description of the surgical technique and to review the current state retroperitoneal robot-assisted partial nephrectomy (rRAPN).

RECENT FINDINGS

Partial nephrectomy is the standard treatment for localized kidney tumours. rRAPN is especially useful for kidney tumours of posterior location. It offers advantages such as direct access to the renal artery and no need for bowel mobilization. The disadvantages are the small working space and the less familiar anatomical landmarks. It is a reproducible technique that achieves similar oncological and functional results to the more traditional transperitoneal route (tRAPN). High-quality randomized studies are needed to ascertain the role of new technologies as modern high-flow insufflation systems, intracavitary ultrasound, 3D planning, and augmented reality (AR), in the performance of this operation. rRAPN is especially useful for kidney tumours of posterior location. Robotic surgeons ideally should become familiar with both approaches, transperitoneal or retroperitoneal.

Comparison of Outcomes Between Transperitoneal and Retroperitoneal Robotic Partial Nephrectomy: A Meta-Analysis Based on Comparative Studies

Background

To compare perioperative, functional and oncological outcomes between transperitoneal robotic partial nephrectomy (TRPN) and retroperitoneal robotic partial nephrectomy (RRPN).

Methods

A literature searching of Pubmed, Embase, Cochrane Library and Web of Science was performed in August, 2020. Pooled odds ratios (ORs) or weighted mean differences (WMDs) with 95% confidence intervals (CIs) were estimated using fixed-effect or random-effect model. Publication bias was evaluated with funnel plots. Only comparative studies with matched design or similar baseline characteristics were included.

Results

Eleven studies embracing 2,984 patients were included. There was no significant difference between the two groups regarding conversion to open (P = 0.44) or radical (P = 0.31) surgery, all complications (P = 0.06), major complications (P = 0.07), warm ischemia time (P = 0.73), positive surgical margin (P = 0.87), decline in eGFR (P = 0.42), CKD upstaging (P = 0.72), and total recurrence (P = 0.66). Patients undergoing TRPN had a significant higher minor complications (P = 0.04; OR: 1.39; 95% CI, 1.01–1.91), longer operative time (P < 0.001; WMD: 21.68; 95% CI, 11.61 to 31.76), more estimated blood loss (EBL, P = 0.002; WMD: 40.94; 95% CI, 14.87 to 67.01), longer length of hospital stay (LOS, P < 0.001; WMD: 0.86; 95% CI, 0.35 to 1.37). No obvious publication bias was identified.

Conclusion

RRPN is more favorable than TRPN in terms of less minor complications, shorter operative time, less EBL, and shorter LOS. Methodological limitations of the included studies should be considered while interpreting these results.

Transperitoneal vs retroperitoneal minimally invasive partial nephrectomy: comparison of perioperative outcomes and functional follow-up in a large multi-institutional cohort (The RECORD 2 Project)

BACKGROUND

Aim of this study was to evaluate and compare perioperative outcomes of transperitoneal (TP) and retroperitoneal (TR) approaches in a multi-institutional cohort of minimally invasive partial nephrectomy (MI-PN).

MATERIAL AND METHODS

All consecutive patients undergone MI-PN for clinical T1 renal tumors at 26 Italian centers (RECORd2 project) between 01/2013 and 12/2016 were evaluated, collecting the pre-, intra-, and postoperative data. The patients were then stratified according to the surgical approach, TP or RP. A 1:1 propensity score (PS) matching was performed to obtain homogeneous cohorts, considering the age, gender, baseline eGFR, surgical indication, clinical diameter, and PADUA score.

RESULTS

1669 patients treated with MI-PN were included in the study, 1256 and 413 undergoing TP and RP, respectively. After 1:1 PS matching according to the surgical access, 413 patients were selected from TP group to be compared with the 413 RP patients. Concerning intraoperative variables, no differences were found between the two groups in terms of surgical approach (lap/robot), extirpative technique (enucleation vs standard PN), hilar clamping, and ischemia time. Conversely, the TP group recorded a shorter median operative time in comparison with the RP group (115 vs 150 min), with a higher occurrence of intraoperative overall, 21 (5.0%) vs 9 (2.1%); p = 0.03, and surgical complications, 18 (4.3%) vs 7 (1.7%); p = 0.04. Concerning postoperative variables, the two groups resulted comparable in terms of complications, positive surgical margins and renal function, even if the RP group recorded a shorter median drainage duration and hospital length of stay (3 vs 2 for both variables), p < 0.0001.

CONCLUSIONS

The results of this study suggest that both TP and RP are feasible approaches when performing MI-PN, irrespectively from tumor location or surgical complexity. Notwithstanding longer operative times, RP seems to have a slighter intraoperative complication rate with earlier postoperative recovery when compared with TP.

Comparisons of surgical outcomes between transperitoneal and retroperitoneal approaches in robot-assisted laparoscopic partial nephrectomy for lateral renal tumors: a propensity score-matched comparative analysis

OBJECTIVE

To compare the surgical outcomes between the transperitoneal (TP) and retroperitoneal (RP) approaches in robot-assisted laparoscopic partial nephrectomy (RAPN) for lateral tumors.

METHODS

This study included patients who underwent RAPN for lateral renal tumors between 2013 and 2019. Lateral tumors were defined as X of A factors in the RENAL nephrometry score. In total, 290 and 48 patients with TP and RP, respectively, were included in the analysis. To minimize the effects of selection bias, the following variables were adjusted using 1:1 propensity score matching: age, sex, body mass index, American Society of Anesthesiologists score, preoperative estimated glomerular filtration rate, tumor size, and RENAL nephrometry score.

RESULTS

After matching, 48 patients were allocated to each group. The mean age was 55 years, and the mean preoperative estimated glomerular filtration rate (eGFR) was 68-69 mL/min/1.73 m². The mean tumor size was 30-31 mm. The RP group had a shorter operative time (124 vs. 151 min, p = 0.0002), shorter console time (74 vs. 110 min, p < 0.0001), shorter warm ischemic time (14 vs. 17 min, p = 0.0343), lower estimated blood loss (EBL) (33 vs. 52 ml, p = 0.0002), and shorter postoperative length of hospital stay (PLOS) (3.3 vs. 4.0 days, p < 0.0001) than the TP group. The change in eGFR, incidence rate of perioperative complication, and positive surgical margin rate did not significantly differ between the two groups.

CONCLUSION

RP had better surgical outcomes, including shorter operative time, lower EBL, and shorter PLOS for lateral renal tumors, which may suggest that RP is the optimal approach for selected lateral renal tumors.