Off-clamp Partial Nephrectomy Research Articles

IJU this issue

This issue contains three Review Articles, four Original Articles and four Urological Notes. Huge differences in the incidence and mortality rate of prostate cancer were detected between the USA and Japan. Such differences, however, have been decreasing over time, and were only twofold in 2017. Ito et al. (Takasaki, Japan) describe the important issue of screening for prostate cancer. They propose their screening strategies based on baseline prostate-specific antigen with a reasonable incremental cost-effectiveness ratio. In their perspectives, prostate cancer management might not only be aimed at decreasing the mortality of prostate cancer, but also aimed at achieving a significant increase in the quality-adjusted life year with an acceptable incremental cost-effectiveness ratio. The cancer-specific mortality among patients with localized prostate cancer has been reported to be very low irrespective of the treatment modalities. Nakamura et al. (Hamamatsu, Japan) focus on the patients’ quality of life after external beam radiotherapy using X-ray for prostate cancer, compared with other modalities, including radical prostatectomy and brachytherapy. In conclusion, the patients’ quality of life after external beam radiotherapy is strongly related to the total dose, fractionation regimens, dose parameters of the critical organs, beam delivery techniques and treatment plan quality, with a trade-off between the radicality of external beam radiotherapy and potentially increased toxicity. Particle beam radiotherapy (RT) for prostate cancer in Japan has changed considerably, and it is eligible for insurance coverage as of April 2018. Ishikawa et al. (Tsukuba, Japan) review the results of previous particle beam RT studies compared with photon beam RT, and introduce ongoing studies and prospects to establish high-quality evidence for particle beam RT for prostate cancer. Androgen deprivation therapy (ADT), a standard treatment for metastatic and locally advanced prostate cancer, is known to increase the risks of osteoporosis and fractures. Kimura et al. (Tokyo, Japan) prospectively investigated changes in bone quality, turnover markers and bone mineral density before and after ADT in castration-sensitive prostate cancer. They found that bone quality markers did not change significantly after ADT, whereas bone mineral density decreased significantly after ADT. Bone turnover markers might play an important role in monitoring bone health during ADT. Simone et al. (Rome, Italy) carried out propensity score-matched analysis to compare long-term renal functional outcomes after either off-clamp partial nephrectomy (PN) or on-clamp PN in patients with cT1–2/N0 M0 renal tumors. This study shows that off-clamp PN is associated with a significantly higher probability of maintaining 100% estimated glomerular filtration rate after surgery compared with on-clamp PN in patients with good baseline renal function. It also showed that patients treated with on-clamp PN had a 7.3-fold increased risk of developing a severe chronic kidney disease during long-term follow up. Molecular-targeted therapies have been generally used for treatment of metastatic renal cell carcinoma (mRCC), resulting in improvement in prognoses of mRCC. Konishi et al. (Hirosaki, Japan) retrospectively investigated the impact of C-reactive protein/albumin ratio (CAR) on prognosis, and the effect of adding CAR in the International Metastatic Renal Cell Carcinoma Database Consortium model for prognosis discrimination in Japanese patients who were treated with first-line tyrosine kinase inhibitor for mRCC. They concluded that CAR is an independent predictor of prognosis in patients with mRCC. Predictive activity was significantly improved in the International Metastatic Renal Cell Carcinoma Database Consortium-CAR model compared with the International Metastatic Renal Cell Carcinoma Database Consortium model. Kam et al. (Sydney, Australia) compared the operative performance of two single-use digital flexible ureteroscopes (fURS) with a reusable video fURS in order to show that single-use fURS would have a similar performance to reusable fURS with a lower scope failure rate. In conclusion, these single-use scopes offer a feasible alternative to reusable fURS, especially in complex stone cases where the risk of scope damage is high. None declared.

Effects of a Novel Piezo Actuator-driven Pulsed Water Jet System on Residual Kidney After Partial Nephrectomy in a Rat Model

To evaluate renal damage after off-clamp partial nephrectomy (PN) using a novel surgical device, piezo actuator-driven pulsed water jet (ADPJ) system. Sprague-Dawley rats were divided into 4 groups and subjected to sham operation, off-clamp PN by the piezo ADPJ system, radio knife, and soft coagulation, which have been used as thermal coagulation devices. Urine and blood samples were collected, and residual kidneys were harvested at 1, 7, 14, 30, and 90 days after PN. Serum blood urea nitrogen, creatinine, and urinary and serum kidney injury molecule-1 KIM-1 levels were measured. Morphological features and the extent of renal ischemia of resection surfaces were evaluated by hematoxylin-eosin staining and immunostaining using antibodies to 1-methyladenosine, respectively. In addition, the expression levels of KIM-1 mRNA extracted from each resection surface were analyzed by quantitative real-time reverse transcription polymerase chain reaction. Serum blood urea nitrogen and creatinine were significantly lower with the piezo ADPJ system than with soft coagulation. Urinary and serum KIM-1 levels were also significantly decreased with the ADPJ. The extent of 1-methyladenosine immunostaining was significantly less with the ADPJ than with thermal coagulation devices. The expression levels of KIM-1 mRNA were also lower in the ADPJ system group. The piezo ADPJ system might attenuate renal damage after off-clamp PN.

The role of RENAL, PADUA and C-index scoring systems in predicting the results of partial nephrectomy without ischemia

To evaluate the feasibility and renoprotective effect of off-clamp partial nephrectomy (PN) by renal scoring systems. After approval of the local ethics committee, the radiological and clinical data of patients with renal masses who underwent PN between January 2012 and January 2017 were evaluated in two university hospitals. Total 132 patients who underwent open surgery and off-clamp technique were included. All patients underwent contrast-enhanced computed tomography (CT) or magnetic resonance imaging (MRI) preoperatively. Preoperative demographic data, estimated glomerular filtration rate (e-GFR) and hematocrit changes, operation time, tumor volume and hospitalization time from patients were evaluated separately and statistically for each of the three scoring systems. Our study consisted of 132 patients with a mean age of 53.9±13.9 with 69 male and 63 female. Statistically significant difference between the risk groups in RENAL and PADUA scoring were found according to tumor T stage and tumor volüme (p <0.005). Statistically significant difference was only found between risk groups of RENAL scoring system in e-GFR reduction (p<0.05). There was no statistically significant difference between the groups in the complications of all three classification systems (p>0.005). In our study, all three scoring sytem successfully predicted the surgical complexity ve surgical outcomes and our results indicate that off-clamp PN has similar success and complications rates when compared to the literature. The off-clamp PN must be kept in mind to maintain postoperative renal functions eligible patients.

Off-clamp partial nephrectomy has a positive impact on short- and long-term renal function: a systematic review and meta-analysis

BackgroundOngoing efforts are focused on shortening ischemia intervals as much as possible during partial nephrectomy to preserve renal function. Off-clamp partial nephrectomy (off-PN) has been a common strategy for to avoid ischemia in small renal tumors. Although studies comparing the advantages between off-PN with conventional on-clamp partial nephrectomy (on-PN) have been reported, the impact on short- and especially long-term renal function of the two surgical methods has not been discussed seriously and remained unclear. Our purpose is to evaluate the impact on short- (within postoperative 3 months) and long-term (postoperative 6 months or longer) renal function of off-PN compared with that of on-PN.MethodsWe comprehensively searched databases, including PubMed, EMBASE, and the Cochrane Library, without restrictions on language or region. A systematic review and cumulative meta-analysis of the included studies were performed to assess the impact of the two techniques on short- and long-term renal function.ResultsA total of 23 retrospective studies and 2 prospective cohort studies were included. The pooled postoperative short-term decrease of estimated glomerular filtration rate (eGFR) was significantly less in the off-PN group (weighted mean difference [WMD]: 4.81 ml/min/1.73 m2; 95% confidence interval [CI]: 3.53 to 6.08; p < 0.00001). The short-term increase in creatinine (Cr) level in the on-PN group was also significant (WMD: − 0.05 mg/dl; 95%CI: − 0.09 to − 0.00; p = 0.04). Significant differences between groups was observed for the long-term change and percent (%) change of eGFR (p = 0.04 and p < 0.00001, respectively) but not for long-term Cr change (p = 0.40). The postoperative short-term eGFR and Cr levels, but not the postoperative long-term eGFR, differed significantly between the two groups. The pooled odds ratios for acute renal failure and postoperative progress to chronic kidney disease (stage≥3) in the off-PN group were found to be 0.25 (p = 0.003) and 0.73 (p = 0.34), respectively, compared with the on-PN group.ConclusionsOff-PN exerts a positive impact on the short- and long-term renal function compared with conventional on-PN. Given the inherent limitations of our included studies, large-volume and well-designed RCTS with extensive follow up are needed to confirm and update the conclusion of this analysis.

Off-Clamp Robotically-Assisted Partial Nephrectomy in Polycystic Kidney Disease

Abstract Introduction: Partial nephrectomy (PN) in autosomal dominant polycystic kidney disease (PCKD) is desirable in the setting of chronic kidney disease, but presents a technical challenge beca...

On-clamp versus off-clamp partial nephrectomy: Propensity score matched comparison of long term functional outcomes

On-clamp versus off-clamp partial nephrectomy: Propensity score matched comparison of long term functional outcomes

Laparoscopic Off-Clamp Partial Nephrectomy for Renal Tumours with Moderate to High R.E.N.A.L. Nephrometry Scores

Laparoscopic Off-Clamp Partial Nephrectomy for Renal Tumours with Moderate to High R.E.N.A.L. Nephrometry Scores

A novel approach to off-clamp partial nephrectomy demonstrates significant improvements in renal injury in an experimental porcine model.

We sought to design a partial nephrectomy (PN) with contralateral total nephrectomy porcine model and assess the underlying mechanisms of ischemia reperfusion injury (IRI) after PN using a novel, clinically approved resection device. Domestic male pigs (n=9) underwent left lower pole PN, allocated to either standard (Group 1) or no ischemia PN (Group 2), followed by contralateral nephrectomy. Biochemical studies were performed at baseline, Day 2, and Day 7; after sacrifice, kidneys were processed for histological analysis. Apoptotic markers were measured by Western blot analyses. Urinary biomarkers were measured to assess acute kidney injury. At Day 2 following PN, there was a significant rise in serum creatinine in Group 1 compared to Group 2 (355 vs. 136 mmol/L; p=0.008). Intra-renal tissue oxygen saturation after PN was inversely correlated with postoperative creatinine (rs -0.75; p=0.012) and the grade of acute tubular necrosis (rs -0.70; p=0.036). We observed a rise in expression of pro-apoptotic markers and pro-inflammatory markers in Group 1 following PN compared to Group 2. Histological analysis revealed higher grade of apoptosis in Group 1. IRI associated with standard PN has a deleterious impact on acute renal function, markers of tissue injury, and histological parameters, compared to off-clamp PN using the ALTRUS device. We identified several intraoperative and postoperative markers that may be used as predictors for functional and histological injury following PN.

Evolution of Technique from Minimally Ischemic to Pure Off-Clamp Partial Nephrectomy: 15-Year Learning Curve and Outcomes of 1083 Patients

Introduction and Objective: There is a growing interest in surgical techniques aimed at minimizing ischemia during partial nephrectomy (PN). The aim of this video is to report surgical tips, perioperative, functional, and oncologic outcomes of first 1083 patients treated with laparoscopic or robotic minimally ischemic1,2 or pure off-clamp (Off-C) PN treated between 2002 and 2015 in a high-volume center. Materials and Methods: Patients were placed in an extended flank position and a four-port or five-port access was performed for laparoscopic or robotic approach, respectively. Hilar vessels were not clamped in any case; pure or hybrid tumor enucleation was the resection technique used. The first case shows a robotic PN with the “sutureless technique” for more exophytic masses, which can also be performed with a laparoscopic approach.3 The second video shows a 4 cm left mesorenal tumor treated with laparoscopic PN after superselective transarterial embolization.4–6 This original technique, first used in 2003, at the beginning of the learning curve, has been no longer used since 2010. The third video shows a robotic PN in a right solitary kidney, affected by a 4.3 cm tumor involving the medial aspect of the upper pole. Small arterial feeders identified or transected during the enucleation of the tumor were selectively coagulated. Two suction devices were used simultaneously to maintain a bloodless surgical field. A point-specific hemostasis was performed before starting a sliding clip renorrhaphy. Results: Overall complication rate was 15.7% with a transfusion rate of 7.8%. Only 4.25% of complications were severe with a Clavien grade equal to or greater than 3. Five-year local recurrence-free survival and cancer-specific survival rates were 98.1% and 98%, respectively. The 5-year risk of severe renal function (RF) deterioration (chronic kidney disease (CKD) stage 4) was 0%, 0.9%, 7.5%, and 10.7% for patients with stages 1, 2, 3A, and 3B CKD, respectively. At multivariable analysis, baseline RF (p = 0.001) and postoperative RF decrease ≥10% (p = 0.048) independently predicted a new onset stage 4 or 5 CKD. Conclusions: Off-C PN is a challenging surgical procedure. At the beginning of learning curve, a stepwise adoption of pure Off-C approach is mandatory and preparing hilar vessels for intermediate and high nephrometry score renal tumors is recommended. Oncologic outcomes were comparable with on-clamp PN series and excellent functional outcomes of our series support Off-C as a first line treatment option in high-volume tertiary referral centers. No competing financial interests exist. Runtime of video: 5 mins 5 secs Presented at the World Congress of Endourology in Cape Town, South Africa, November 2016.

785 - On-clamp versus off-clamp partial nephrectomy: Propensity score matched comparison of long term functional outcomes

785 - On-clamp versus off-clamp partial nephrectomy: Propensity score matched comparison of long term functional outcomes

The Piezo Actuator-Driven Pulsed Water Jet System for Minimizing Renal Damage after Off-Clamp Laparoscopic Partial Nephrectomy.

In the setting of partial nephrectomy (PN) for renal cell carcinoma, postoperative renal dysfunction might be caused by surgical procedure. The aim of this study was to clarify the technical safety and renal damage after off-clamp laparoscopic PN (LPN) with a piezo actuator-driven pulsed water jet (ADPJ) system. Eight swine underwent off-clamp LPN with this surgical device, while off-clamp open PN was also performed with radio knife or soft coagulation. The length of the removed kidney was 40 mm, and the renal parenchyma was dissected until the renal calyx became clearly visible. The degree of renal degeneration from the resection surface was compared by Hematoxylin-Eosin staining and immunostaining for 1-methyladenosine, a sensitive marker for the ischemic tissue damage. The mRNA levels of neutrophil gelatinase-associated lipocalin (Ngal), a biomarker for acute kidney injury, were measured by quantitative real-time PCR. Off-clamp LPN with ADPJ system was successfully performed while preserving fine blood vessels and the renal calix with little bleeding. In contrast to other devices, the resection surface obtained with the ADPJ system showed only marginal degree of ischemic changes. Indeed, the expression level of Ngal mRNA was lower in the resection surface obtained with the ADPJ system than that with soft coagulation (p = 0.02). Furthermore, using the excised specimens of renal cell carcinoma, we measured the breaking strength at each site of the human kidney, suggesting the applicability of this ADPJ to clinical trials. In conclusion, off-clamp LPN with the ADPJ system could be safely performed with attenuated renal damage.

Laparoscopic Off-Clamp Unsutured Partial Nephrectomy Using Soft Coagulation for a Large Renal Angiomyolipoma After Transarterial Embolization for Rupture

Abstract Introduction: Transarterial embolization (TAE) and partial nephrectomy (PN) are the standard treatments for a symptomatic or large renal angiomyolipoma (AML).1 PN for AML has shown high success rates and fewer retreatments than TAE. Recently, indications for laparoscopic PN have been expanded to large renal tumors to preserve renal function. We report a case of large AML effectively treated by laparoscopic off-clamp unsutured PN using soft coagulation2,3 after TAE for ruptured AML. Patient and Method: The patient was a 53-year-old female with complaints of left flank pain and vomiting. After diagnosis of the spontaneous rupture of the AML (85 × 81 mm), TAE was performed in a community hospital. Since the size of the tumor had not sufficiently decreased, she was referred to our clinic for surgery. Laparoscopic off-clamp PN was performed. The tumor resection was carried out using soft coagulation with the combination of monopolar scissors and bipolar forceps, without hilum clamping. Soft coagulatio...

The zero ischemia index (ZII): a novel criterion for predicting complexity and outcomes of off-clamp partial nephrectomy.

Although several anatomical classification systems that aimed to standardize the description of renal tumors were previously reported, a special classification system is required to help predict the complexity and perioperative outcomes of off-clamp nephron-sparing surgery (NSS). We developed a novel criterion-zero ischemia index (ZII), aiming to help predict the perioperative outcomes after off-clamp NSS and guide patient selection. We retrospectively evaluated 149 patients between June 2009 and July 2014 in our institution who underwent off-clamp NSS with available computed tomography images. ZII was defined as the product of the tumor diameter and depth within renal parenchyma. ZII was then analyzed to investigate its association with perioperative outcomes. A specific ZII score was further selected to best guide patient selection in off-clamp NSS. ZII was significantly associated with estimated blood loss>500mL (OR 1.270, 95% CI 1.036-1.557, p=0.021), operative time>2h (OR 1.286, 95% CI 1.051-1.573, p=0.014), surgical complications (OR 1.251, 95% CI 1.035-1.511, p=0.020), overall complications (OR 1.208, 95% CI 1.016-1.436, p=0.032), and >10% decrease in estimated glomerular filtration rate (OR 1.362, 95% CI 1.045-1.776, p=0.022). Patients with ZII>6 may bear a higher risk of hemorrhage, perioperative complications, and a longer operative time, if they underwent an off-clamp NSS, compared to those with ZII≤6. The ZII is a novel and readily measurable criterion which can help predict renal complexity of tumor and risk of perioperative outcomes after off-clamp NSS. ZII=6 is established as a preliminary threshold for patient selection of off-clamp NSS. A more robust criterion is to be validated with more samples in a prospective study.

Patient-specific 3-dimensional Printed Kidney Designed for “4D” Surgical Navigation: A Novel Aid to Facilitate Minimally Invasive Off-clamp Partial Nephrectomy in Complex Tumor Cases

To report our initial experience with a novel style of 3-dimensional (3D) printed kidney, which we call "4D" surgical navigation in minimally invasive off-clamp partial nephrectomy (PN). Ten patients with a R.E.N.A.L. nephrometry score ≥8 renal mass underwent minimally invasive off-clamp PN navigated with the aid of a patient-specific 3D printed kidney. To enhance the advantage of a 3D printed organ, we herein designed our 3D printed kidneys so that the tumor and its margin could be removed. This tumor removability allowed surgeons and patients to preoperatively visualize both the pre- and posttumor-resection kidney status, which we termed "4D" surgical navigation. Before patients consented to surgery, the surgical procedure and perioperative risks were explained to each patient using the patient-specific 3D printed kidney; subsequently, surgeons asked patients whether the 3D printed kidney model had helped them better understand their surgery than they would have without the model. All minimally invasive off-clamp PNs were successfully completed with acceptable perioperative outcomes and negative surgical margins. The 3D printed tumors together with their margins were nearly identical to the surgical specimens. All patients responded that their specific 3D printed kidney models had helped them understand their disease and the operations they underwent. This is the first report of a novel 3D printed organ style, which we termed "4D" surgical navigation. Use of the current 3D printed kidney models helped surgeons to perform minimally invasive off-clamp PN in complex tumor cases and also helped patients to more fully understand the operation.

Indications, Techniques, Outcomes, and Limitations for Minimally Ischemic and Off-clamp Partial Nephrectomy: A Systematic Review of the Literature

ContextOn-clamp partial nephrectomy (PN) has been considered the standard approach to minimize intraoperative bleeding and thus achieve adequate control of tumor margins. The potential negative impact of ischemia on renal function (RF) led to the development of techniques to minimize or avoid renal ischemia, such as off-clamp PN and minimally ischemic PN techniques. ObjectiveTo review current evidence on the indications and techniques for and outcomes of minimally ischemic and off-clamp PN. Evidence acquisitionA systematic review of English-language publications on PN without a main renal artery clamp from January 2005 to July 2014 was performed using the Medline, Embase, and Web of Science databases. Evidence synthesisThe searches retrieved 52 papers. Off-clamp PN has been more commonly applied to small and peripheral renal tumors, while minimally ischemic PN is best suited for hilar and medially located renal tumors. These approaches are associated with increased intraoperative blood loss and perioperative transfusion rates compared to on-clamp PN. Minimally ischemic and off-clamp PN have potential functional benefits when longer ischemia time is anticipated, particularly for patients with lower baseline RF. Limitations include the lack of prospective randomized trials comparing minimally ischemic and off-clamp to on-clamp techniques, and the small sample size and short follow-up of most published series. The impact of different resection and renorrhaphy techniques on postoperative RF and its assessment via renal scintigraphy requires further investigations. ConclusionsMinimally ischemic and off-clamp PN are established procedures that may be particularly applicable for patients with decreased baseline RF. However, these techniques are technically demanding, with potential for increased blood loss, and require considerable experience with PN surgery. The role of ischemia in patients with a contralateral healthy kidney and consequently an indication for elective minimally ischemic or off-clamp PN remains a debatable issue. Patient summaryIn this review we analyzed available evidence on minimally ischemic and off-clamp partial nephrectomy. These techniques, although technically demanding, may be particularly applicable for patients with decreased baseline renal function.

Cook resonance metallic ureteric stent: Contemporary clinical series assessing feasibility, safety and efficacy

Cook resonance metallic ureteric stent: Contemporary clinical series assessing feasibility, safety and efficacy

Comparison of off-clamp partial nephrectomy and on-clamp partial nephrectomy: A systematic review and meta-analysis

Objective: To compare peri- and postoperative variables, surgical complications, oncological outcomes and renal outcomes of off-clamp partial nephrectomy (PN) and on-clamp PN. Methods: A systematic search of the electronic databases, including MEDLINE, Embase and Cochrane Library, was performed. The pooled estimates of tumour size, operative time, estimated blood loss, length of stay, overall complications, transfusion rates, urinary leaks, positive surgical margins and eGFR were calculated. Results: 14 studies were included. There was no significant difference between off-clamp PN and on-clamp PN in terms of tumour size, operative time, estimated blood loss, length of stay, overall complications, transfusion rates, urinary leaks, and positive surgical margins. However, a non-statistically significant trend towards increased blood loss (p = 0.12) and transfusion rates (p = 0.07) in those undergoing off-clamp PN was noted. Off-clamp PN was associated with a significantly lower reduction in eGFR than on-clamp PN (standardised weighted mean difference 0.27, 95% CI 0.14, 0.40, p Conclusions: Off-clamp PN may be associated with improved long-term renal outcomes when compared to on-clamp PN with no difference in in peri- and postoperative variables, surgical complications and oncological outcomes. However, the meta-analysis was limited by the design of the underlying studies, and hence further work is necessary.

Comparison of Off-Clamp Partial Nephrectomy and On-Clamp Partial Nephrectomy: A Systematic Review and Meta-Analysis

Objective: To compare peri- and postoperative variables, surgical complications, oncological outcomes and renal outcomes of off-clamp partial nephrectomy (PN) and on-clamp PN. Methods: A systematic search of the electronic databases, including MEDLINE, Embase and Cochrane Library, was performed. The pooled estimates of tumour size, operative time, estimated blood loss, length of stay, overall complications, transfusion rates, urinary leaks, positive surgical margins and eGFR were calculated. Results: 14 studies were included. There was no significant difference between off-clamp PN and on-clamp PN in terms of tumour size, operative time, estimated blood loss, length of stay, overall complications, transfusion rates, urinary leaks, and positive surgical margins. However, a non-statistically significant trend towards increased blood loss (p = 0.12) and transfusion rates (p = 0.07) in those undergoing off-clamp PN was noted. Off-clamp PN was associated with a significantly lower reduction in eGFR than on-clamp PN (standardised weighted mean difference 0.27, 95% CI 0.14, 0.40, p < 0.0001). Conclusions: Off-clamp PN may be associated with improved long-term renal outcomes when compared to on-clamp PN with no difference in in peri- and postoperative variables, surgical complications and oncological outcomes. However, the meta-analysis was limited by the design of the underlying studies, and hence further work is necessary.

Novel pulsed water jet system permits off-clamp partial nephrectomy in swine.

Novel pulsed water jet system permits off-clamp partial nephrectomy in swine.

Off-Clamp Versus Complete Hilar Control Partial Nephrectomy for Renal Cell Carcinoma: A Systematic Review and Meta-Analysis

To evaluate the safety, efficacy, and potential advantages of off-clamp partial nephrectomy (OFF-PN) compared with on-clamp partial nephrectomy (ON-PN). Relevant studies comparing the safety and efficacy of OFF-PN to ON-PN were identified through a literature search using MEDLINE, EMBASE, and the Cochrane Library. The outcome measures included baseline characteristics, primary outcomes, and secondary outcomes. Ten retrospective studies (728 cases and 1267 controls) were included. No significant differences between the two groups were detected in any of the baseline variables (age: p=0.19; sex: p=0.49; BMI: p=0.29; tumor size: p=0.44, pre-eGFR: p=0.78) except for tumor location (p<0.001). The OFF-PN group had a higher blood transfusion rate (odds ratio [OR] 1.54, 95% confidence interval [CI] 10.7-2.21, p=0.02), a lower postoperative complication rate (OR 0.61, 95% CI 0.44-0.83, p=0.002), and a lower positive margin rate (OR 0.49, 95% CI 0.26-0.90, p=0.02) than ON-PN. OFF-PN offered a better preservation of renal function than ON-PN (p=0.005). No significant differences were detected between the two groups in other outcomes of interest. In sensitivity analysis, there was no change in the significance of any of the outcomes except for postoperative complication rate (OR 0.91, 95% CI 0.53-1.5, p=0.73) and positive margin rate (OR 0.55, 95% CI 0.25-1.23, p=0.15). This meta-analysis suggests that with appropriate patient selection, OFF-PN offer comparable perioperative safety, equivalent oncologic outcomes, and superior long-term renal function preservation when compared with ON-PN for renal cell carcinoma. Given the inherent limitations of the included studies, future well-designed randomized controlled trials are required to confirm our findings.