Early unclamping might reduce the risk of renal artery pseudoaneurysm after robot-assisted laparoscopic partial nephrectomy

Timing, incidence and management of delayed bleeding after partial nephrectomy in patients at risk for recurrent, bilateral, multifocal renal tumors

INTRODUCTION

Delayed bleeding is a potentially serious complication after partial nephrectomy (PN), with reported rates of 1%-2%. Patients with multiple renal tumors, including those with hereditary forms of kidney cancer, are often managed with resection of multiple tumors in a single kidney which may increase the risk of delayed bleeding, though outcomes have not previously been reported specifically in this population. The objective of this study was to evaluate the incidence and timing of delayed bleeding as well as the impact of intervention on renal functional outcomes in a cohort primarily made up of patients at risk for bilateral, multifocal renal tumors.

METHODS

A retrospective review of a prospectively maintained database of patients with known or suspected predisposition to bilateral, multifocal renal tumors who underwent PN from 2003 to 2023 was conducted. Patients who presented with delayed bleeding were identified. Patients with delayed bleeding were compared to those without. Comparative statistics and univariate logistic regression were used to determine potential risk factors for delayed bleeding.

RESULTS

A total of 1256 PN were performed during the study period. Angiographic evidence of pseudoaneurysm, AV fistula and/or extravasation occurred in 24 cases (1.9%). Of these, 21 were symptomatic presenting with gross hematuria in 13 (54.2%), decreasing hemoglobin in 4(16.7%), flank pain in 2(8.3%), and mental status change in 2 (8.3%), while 3 patients were asymptomatic. Median number of resected tumors was 5 (IQR 2-8). All patients underwent angiogram with super-selective embolization. Median time to bleed event was 13.5 days (IQR 7-22). Factors associated with delayed bleeding included open approach (OR 2.2, IQR(1.06-5.46), P = 0.04 and left-sided surgery (OR 4.93, IQR(1.67-14.5), P = 0.004. Selective embolization had little impact on ultimate renal functional outcomes, with a median change of 11% from the baseline eGFR after partial nephrectomy and embolization. One patient required total nephrectomy for refractory bleeding after embolization.

CONCLUSIONS

Delayed bleeding after PN in a cohort of patients with multifocal tumors is an infrequent event, with similar rates to single tumor series. Patients should be counseled regarding timing and symptoms of delayed bleeding and multidisciplinary management with interventional radiology is critical for timely diagnosis and treatment.

Renal anatomical classification systems cannot predict the occurrence of vascular complications after partial nephrectomy

OBJECTIVES

To determine the relationship between renal tumor complexity and vascular complications after partial nephrectomy using PADUA, RENAL, and ZS scores.

METHODS

Between January 2007 and December 2018, a total of 1917 patients with available cross-sectional imaging were enrolled in the study. Logistic regressions were used to identify independent predictors of vascular complications.

RESULTS

Of 1917 patients, 31 (1.6%) developed vascular complications, including 10 females and 21 males. The high-complexity category was significantly associated with a decreased risk of vascular complication in PADUA (OR = 0.256; 95%CI = 0.086-0.762; P = 0.014) and ZS score (OR = 0.279; 95%CI = 0.083-0.946; P = 0.040). Laparoscopic partial nephrectomy and robot-assisted laparoscopic partial nephrectomy were independent risk factors for vascular complications. Meanwhile, the incidence was significantly reduced in the recent 4 years in the high score tumor group alone in PADUA (0.2% [1/474] vs. 2.2% [3/139], P = 0.038) and ZS score (0.2% [1/469] vs. 2.7% [3/112], P = 0.024). In the first 8 years, laparoscopic partial nephrectomy and robot-assisted laparoscopic partial nephrectomy were the only two independent risk factors for vascular complications. In the recent 4 years, only the high-complexity category was significantly associated with a decreased risk of vascular complication in the PADUA score (OR = 0.110; 95%CI = 0.013-0.938; P = 0.044).

CONCLUSION

The renal anatomic classification system cannot predict the occurrence of vascular complications after partial nephrectomy.

Surgical and functional outcomes of repeat robot-assisted laparoscopic partial nephrectomy compared with repeat open partial nephrectomy

OBJECTIVES

To examine the surgical and functional outcomes of patients who have undergone repeat open partial nephrectomy (reOPN) or robot-assisted laparoscopic partial nephrectomy (reRAPN).

METHODS

Until May 2022, 3310 patients with renal tumors underwent nephron-sparing surgery (NSS) at affiliated institutions. Of these, 22 and 17 patients who underwent reOPN and reRAPN, respectively, were included in this study.

RESULTS

No significant differences were found between the groups in terms of sex, age, comorbidities, recurrent tumor size at repeat NSS, interval from recurrence to initial NSS, and nephrometry score. ReRAPN had a shorter operative time (median: 138.0 vs. 214.0 min; p = 0.0023) and less estimated blood loss (median: 50.0 vs. 255.0 mL; p = 0.0261) than reOPN. The incidence of complications with Clavien-Dindo grade ≥ 2 was higher in the reOPN group than in the reRAPN group (31.8 vs. 5.9%; p = 0.0467). The mean decrease in the estimated glomerular filtration rate at 3 months postoperatively was not significantly different between the groups. The trifecta achievement rates in the reRAPN (64.7%) and reOPN (27.3%) groups were significantly different (p = 0.0194). On multivariate analysis, age and surgical method were significant predictors of trifecta achievement after partial nephrectomy.

CONCLUSIONS

There were no differences in postoperative renal functional outcomes between reOPN and reRAPN. ReRAPN is superior to reOPN in terms of surgical burden. Therefore, ReRAPN is an important minimally invasive surgery for recurrent renal cell carcinoma.

Effects of remote ischemic preconditioning on renal protection in patients undergoing robot-assisted laparoscopic partial nephrectomy

We aimed to evaluate the renoprotective effects of remote ischemic preconditioning (RIPC) in patients undergoing robot-assisted laparoscopic partial nephrectomy (RAPN). Data from 59 patients with solitary renal tumors who underwent RAPN with RIPC comprising three cycles of 5-min inflation to 200 mmHg of a blood pressure cuff applied to one lower limb followed by 5-min reperfusion by cuff deflation, from 2018 to 2020 were analyzed. Patients who underwent RAPN for solitary renal tumors without RIPC between 2018 and 2020 were selected as controls. The postoperative estimated glomerular filtration rate (eGFR) at the nadir during hospitalization and the percentage change from baseline were compared using propensity score matching analysis. We performed a sensitivity analysis with imputations for missing postoperative renal function data weighted by the inverse probability of the data being observed. Of the 59 patients with RIPC and 482 patients without RIPC, 53 each were matched based on propensity scores. No significant differences in the postoperative eGFR in mL/min/1.73 m2 at nadir (mean difference 3.8; 95% confidence interval [CI] - 2.8 to 10.4) and its percentage change from baseline (mean difference 4.7; 95% CI - 1.6 to 11.1) were observed between the two groups. Sensitivity analysis also indicated no significant differences. No complications were associated with the RIPC. In conclusion, we found no significant evidence of the protective effect of RIPC against renal dysfunction after RAPN. Further research is required to determine whether specific patient subgroups benefit from RIPC.Trial registration number: UMIN000030305 (December 8, 2017).

Comparison of robot-assisted partial nephrectomy with soft coagulation and double-layer technique for complex and non-complex tumors

OBJECTIVES

To compare the postoperative outcomes of robot-assisted partial nephrectomy when only the inner layer is sutured (single-layer technique with soft coagulation) with those when sutures are placed in the inner and outer layers (double-layer technique) in patients with and without complex renal tumors.

METHODS

This retrospective three-institution study included 371 patients with renal tumors who underwent robot-assisted partial nephrectomy with a double-layer technique or a single-layer technique with soft coagulation. Tumors that were cT1b, completely embedded, located in the renal portal, or had a RENAL score of ≥10 were considered complex. Relevant data were collected from hospital records. Propensity score matching was performed to minimize selection bias.

RESULTS

Propensity score matching created 83 patient pairs with non-complex tumors and 32 with complex tumors. Regardless of tumor complexity, there was no significant difference in operation time, console time, warm ischemia time, positive surgical margin rate, or length of hospital stay between the double-layer and single-layer groups. Although Clavien-Dindo grade I-II urinomas not requiring intervention were significantly more common in the single-layer group regardless of tumor complexity, there was no significant between-group difference in the rate of decline in renal function or grade III-IV complications.

CONCLUSION

Single-layer suturing with soft coagulation achieves renal function and perioperative outcomes comparable to those of double-layer suturing regardless of complexity.

Robotic-assisted partial nephrectomy: single-layer cortical renorrhaphy is associated with reduced rate of renal artery pseudoaneurysm compared to double-layer renorrhaphy

The study compares the outcome of patients who underwent single-layer outer cortical renorraphy (SLOCR) and double-layer cortical renorraphy (DLR) in our institution. The retrospective analysis of 181 patients who underwent RAPN was performed. Propensity score matching was accomplished on 67 patients using age, BMI, size, distance from collecting system, hilar location and pathological stage. Intraoperative factors assessed included warm ischemia time, renorraphy time, blood loss and operative duration (Levey et al. in Clin Chem 53:766-772, 2007) Post-operative hospital stay, complications like renal artery pseudoaneurysm (RAP), hemorrhage, urine leak and reduction in eGFR were measured. The 67 patients in SLOCR group were compared with similar number in the DLR group using propensity score matching. Warm ischemia time (P < .001), renorraphy time (P < .001) and symptomatic pseudoaneurysm (RAP) rate (P < .001) were significantly less in SLOCR group. SLOCR is associated with reduced rate of symptomatic post-operative RAP.

Robot-assisted laparoscopic versus open partial nephrectomy for renal cell carcinoma in patients with severe chronic kidney disease

OBJECTIVES

To compare surgical and functional outcomes between robot-assisted laparoscopic partial nephrectomy and open partial nephrectomy in patients with renal cell carcinoma with stage 4 chronic kidney disease.

METHODS

This was a retrospective analysis of 60 patients with stage 4 chronic kidney disease (estimated glomerular filtration rate 15-30 ml/min/1.73 m² ) who underwent partial nephrectomy for T1 renal cell carcinoma between April 2004 and April 2020. We compared perioperative outcomes according to the surgical approach. Multivariable analysis was performed to identify predictive factors for end-stage renal disease.

RESULTS

Robot-assisted laparoscopic partial nephrectomy and open partial nephrectomy were performed in 31 and 29 patients, respectively. The median age was 68 years and 17% of all patients were women. Patient and tumor characteristics did not differ between groups. The operative time (155.2 vs. 221.0 min, p < 0.0001) and the postoperative length of hospital stay (5.2 vs. 10.6 days, p = 0.0083) were significantly shorter, and the estimated blood loss was lower (53.4 vs. 363.2 ml, p = 0.0003) in the robot-assisted laparoscopic partial nephrectomy group than in the open partial nephrectomy group. Preoperative estimated glomerular filtration rate was the only significant predictor of end-stage renal disease after partial nephrectomy on multivariable analysis.

CONCLUSIONS

Both procedures preserved renal function in this patient cohort, delaying the requirement for postoperative dialysis. Furthermore, robot-assisted laparoscopic partial nephrectomy was associated with shorter operative time and postoperative length of hospital stay, as well as lesser estimated blood loss than open partial nephrectomy.

Surgical and functional outcomes of robot-assisted laparoscopic partial nephrectomy for renal cell carcinoma in adolescents and young adults: a propensity score matching study

BACKGROUND

Cancer development in adolescents and young adults (AYAs) has elicited recent interest. We investigated the surgical and functional outcomes of robot-assisted laparoscopic partial nephrectomy (RAPN) for renal cell carcinoma (RCC) in AYAs.

METHODS

We retrospectively reviewed the medical records of 1023 patients with clinical stage I RCC who underwent RAPN before January 2021. Patients were divided into two groups: AYAs (aged 18-39 years) and non-AYAs (aged 40-89 years). The trifecta criteria, defined as a negative surgical margin, no perioperative complications (Clavien-Dindo grade > 2), and preserved postoperative renal function (1-year postoperative estimated glomerular filtration rate > 90% of baseline), were used to compare outcomes. We performed 1:1 propensity-score matching on the patient cohort.

RESULTS

There were initially 125 and 898 patients in the AYAs and non-AYAs groups, respectively, and 108 patients were included in each group after propensity score matching. There were no significant differences in surgical factors (operation time, clamping ischemia time, estimated blood loss, length of hospital stay, surgical complication rate) or renal function in the early postoperative period. The mean postoperative renal function was better (p = 0.0200) and the decrease in estimated glomerular filtration rate was lower (p = 0.0026) in AYAs than in non-AYAs 12 months postoperatively. The trifecta achievement rates in the AYAs and non-AYAs groups were significantly different (67.6% and 53.7%, respectively, p = 0.0220).

CONCLUSION

Although there was no difference in surgical burden between the groups, the estimated glomerular filtration rate was better preserved in AYAs than in non-AYAs at 6 and 12 months post-RAPN.

Feasibility of interaortocaval clamping for renal artery during robot-assisted right partial nephrectomy: A propensity score-matching analysis

AIM

To evaluate the impact of the interaortocaval clamping technique for the right renal artery on perioperative outcomes of patients who underwent robot-assisted partial nephrectomy (RAPN).

METHODS

This study included 111 consecutive patients with right renal masses undergoing RAPN via the transperitoneal approach. In this series, standard and interaortocaval clamping techniques were defined as those for the right renal artery at the renal hilus and interaortocaval space, respectively. Based on the 3D images reconstructed from CT, interaortocaval clamping was preoperatively selected for patients in whom standard clamping of the main renal artery at the right hilum was judged to be technically difficult due to complicated vascular distribution, such as multiple branches of right renal arteries and veins and/or intertwining of these vessels.

RESULTS

Of 111 patients, 95 and 16 were classified into the standard and interaortocaval clamping groups, respectively, and interaortocaval clamping was uneventfully performed as planned in all 16. After adjusting patient variables by 1:3 propensity score-matching, 33 and 11 patients were included in the respective groups, and there were no significant differences in major clinical characteristics between them, while the incidences of multiple branches of right renal vessels as well as their intertwining beside the right renal hilus were significantly higher in the interaortocaval clamping group. However, no significant difference was noted in any of the perioperative outcomes, including operative time or intraoperative blood loss, between the two groups.

CONCLUSIONS

The interaortocaval clamping technique during RAPN is a feasible procedure with acceptable perioperative outcomes compared with standard hilar clamping, making it possible to more accurately resect renal tumors under clear visualization without unnecessary arterial bleeding from the tumor bed in patients with complex vascular distribution at the right renal hilus; however, special attention should be paid to the considerable individual variability of the interaortocaval anatomy.

Comparison of perioperative outcomes among patients with exophytic, mesophytic, and endophytic renal tumors undergoing robot-assisted partial nephrectomy

OBJECTIVES

It has been well documented that partial nephrectomy for completely endophytic renal tumors is a highly challenging procedure accompanied by several technical difficulties even with the assistance of a robotic surgical system. This study aimed to compare perioperative variables among patients with exophytic, mesophytic, and endophytic renal tumors undergoing robot-assisted partial nephrectomy.

METHODS

This study retrospectively included 265 consecutive patients with localized small renal masses undergoing robot-assisted partial nephrectomy at our institution. In this study, completely endophytic tumor was defined as the mass totally covered by renal healthy parenchyma, and according to the points for the 'E' domain of RENAL nephrometry score based on preoperative computed tomography, subjects were classified into three groups as follows: exophytic, mesophytic, and endophytic tumor groups, and perioperative outcomes among these groups were compared.

RESULTS

Of 265 patients, 127, 112, and 26 were classified into the exophytic, mesophytic, and endophytic tumor groups, respectively. A significantly smaller tumor diameter was observed in the endophytic group than in the other groups (P < 0.001), whereas the RENAL nephrometry score was significantly higher (P < 0.001). In addition, the warm ischemia time in the endophytic tumor group was significantly longer than that in other groups (P = 0.009); however, no significant difference in the trifecta achievement was noted among the three groups.

CONCLUSIONS

This study suggests that robot-assisted partial nephrectomy for patients with completely endophytic tumors can be regarded as a feasible approach without marked impairment of perioperative outcomes; however, further investigation of the long-term functional and oncological outcomes in these patients is required.

Application and clinical efficacy of modified early unclamping technique in robot-assisted laparoscopic partial nephrectomy

OBJECTIVE

To investigate the clinical safety and efficacy of a modified early unclamping technique in robot-assisted laparoscopic partial nephrectomy (RAPN).

METHODS

The clinical data of 38 patients with renal tumors who underwent the modified early unclamping technique in RAPN surgery admitted to the Department of Urology, the Third People's Hospital of Hangzhou and the First Affiliated Hospital of Nanchang University from January 2018 to April 2021 were retrospectively analyzed. The control group consisted of 78 patients with renal tumors who underwent standard clamping during the RAPN surgery completed by the same surgeon during the same period. The perioperative-related indicators and postoperative renal function recovery were analyzed and compared between the two groups.

RESULTS

All patients (n = 116) finished the RAPN successfully, and none were transferred to radical or open surgery in either group. The warm ischemia time in the modified early unclamping group was significantly lower than that in the standard clamping group (P < 0.001). After surgery, the renal function index at each time point in the modified early unclamping group was higher than that in the standard clamping group; renal function gradually returned to near preoperative levels after 3 months in both groups. Postoperative follow-up showed no tumor recurrence or metastasis.

CONCLUSION

The application of a modified early unclamping technique in RAPN surgery is safe and feasible. Compared with standard clamping, modified early unclamping can significantly shorten the warm ischemia time of kidneys without increasing the volume of intraoperative blood loss and complications, which helps to protect the postoperative renal function of patients.

Temporal Study of Renal Volume Losses in Patients with Robotic Partial Nephrectomies

Purpose: Robotic partial nephrectomies (RPNs) by their nature are associated with renal volume loss. Our goal of this study is to examine renal volume loss over time post partial nephrectomy. Materials and Methods: Fifty patients were followed for 1-year post-RPN with two-layer renorrhaphy and the sliding clip technique. This was done with a preoperative CT scan to assess renal mass and location. Patients post-RPN were imaged at time points 3 days, 6 months, and 12 months. Results: Patient demographics were 82% men with a median (interquartile range [IQR]) age of 57 (45-67) years and all were of Japanese descent. The medians (IQR) for warm ischemia time were 18 minutes (14-22), total operative time was 181.5 minutes (169.3-218.5), and estimated blood loss was 20 mL (10-50). The tumor characteristics had a median (IQR) diameter of 2.8 cm (2.5-3.4) with a RENAL score of 7 (6-8). The renal CT showed median (IQR) volume losses at 3 days of -1% (-7.1, 1.8), at 6 months of -15.3% (-20.6, -11.2), and at 12 months of -16.3% (-19.0, -12.8). Significance was seen at the 3 days to 6 months comparison for volume loss (p < 0.0001). Mean (standard deviation) estimated glomerular filtration rate (GFR) losses were as follows: at discharge 0.5% (12.9), 1 month -6.4% (11.8), 6 months -4.6% (9.8), and 12 months -3.6% (11.9). Statistical analysis showed significance for GFR loss at the comparison between discharge to 1 and 6 months (p = 0.01, p = 0.04). Conclusion: The initial volume loss seen postsurgery from resected healthy tissue was not significant and only became relevant at longer time points, suggesting that loss could be from atrophy. Volume loss over time supports the hypothesis that suture renorrhaphy is a primary cause of volume loss when warm ischemia time is <25 minutes.

Clampless Laparoscopic Tumor Enucleation for Exophytic Masses Greater Than 4 cm: Is Renorrhaphy Necessary?

Objective: To demonstrate the safety of clampless 3D laparoscopic tumor enucleation (cLTE) for exophytic T1b kidney masses, avoiding suture to achieve hemostasis. Methods: Between January 2010 and January 2021, 241 consecutive patients with an exophytic renal tumor underwent sutureless cLTE. Patients with predominantly endophytic growth or tumors 4 mm closer to the collecting system less were excluded. In all cases, an attempt was made to accomplish surgery without suturing kidney parenchyma. Data were obtained from a retrospective review of history and physical examinations, operative and pathology reports, anesthesia records during the hospital stay, and follow-up visits. Results: Among 241 patients who underwent cLTE, 148 had cT1a and 93 had cT1b renal tumor. The median tumor size was 32 mm, and the median R.E.N.A.L. (radius exophytic/endophytic nearness anterior/posterior location) score was 6. Renorrhaphy was necessary in 5 cases. The median operative time (OT) was 100 minutes, and the estimated blood loss (EBL) was 150 mL. The median 24-hour decrease in hemoglobin was 1.8 g/dL. The median length of stay was 4 days. Nineteen patients had postoperative complications: 3 cases had Clavien-Dindo (CD) 3a or more, 6 had CD2, and 10 had CD1. Comparing the T1a and T1b groups, except for the median OT and the EBL, no significant differences were observed in all the other variables analyzed. In both groups, renal function was preserved after 1 year from surgery. Conclusion: Our experience showed that sutureless cLTE is safe and feasible for T1b tumors leading to radical oncological outcomes and preserving renal function.

New longitudinal component of the RENAL nephrometry score for predicting the operative complexity in transperitoneal robot-assisted partial nephrectomy

BACKGROUND

In transperitoneal robot-assisted partial nephrectomy (RAPN), an L score of 3 points according to RENAL nephrometry scoring system does not necessarily denote operative complexity. This study aimed to assess the efficacy of the newly defined longitudinal component to analyze the operative complexity of RAPN Methods: We retrospectively analyzed transperitoneal RAPNs performed by a single experienced surgeon for renal tumors between 2017 and 2020. L component was defined as L'1 for medially located tumors, L'2 for >50% below the polar line, and L'3 for >50% above the polar line. Multivariate regression analysis was performed to test associations between prolonged console time and preoperative factors. The perioperative outcomes were compared among the three cohorts of L' components using propensity score matching: L'1 vs. L'3 and L'1 vs. L'2.

RESULTS

A total of 220 cases (L'1: 107, L'2, 65, L'3: 48) were analyzed. The median console time was prolonged (>130 min) in 55 patients (median 108, interquartile range: 90-130 min). Longitudinal location (L'3 odds ratio: 2.93, P = 0.01; L'2 odds ratio: 2.32, P = 0.04), high Mayo adhesive probability score (P = 0.001), multiple renal arteries (P = 0.03), and large size (P = 0.04) were significantly associated with prolonged console time. After matching, 26 cases of L'1 and L'3 and 43 cases of L'1 and L'2 were selected. Console time (132 vs. 108 min, P = 0.017) and warm ischemia time (17 vs. 22 min, P = 0.03) were significantly longer in L'3 than in L'1. The difference in console time between L'1 and L'2 was not statistically significant (100 vs. 111 min, P = 0.08) Conclusion: In the new longitudinal assessment, upper location predicted prolonged console time compared to a medial or lower location. The L' component may help preoperatively assess operative complexity.

Natural history of asymptomatic renal artery pseudoaneurysm after robot-assisted partial nephrectomy

Background

We assessed the natural history of renal artery pseudoaneurysm (RAP) after robot-assisted partial nephrectomy (RAPN).

Methods

From May 2016 to September 2020, 106 patients underwent RAPN for renal tumors at our institution. Among 100 patients, excluding 6 who were ineligible for contrast-enhanced computed tomography (CE-CT), 4 underwent renal artery selective embolization (RAE), of which 2 cases were emergency RAE within 7 days after RAPN and the other 2 were prophylactic RAE 8 or more days after RAPN. In 98 patients examined for the clinical course of asymptomatic RAP managed by surveillance, excluding the 2 who underwent emergency RAE, routine CE-CT was performed at 7 days, 1 month and 3 months after RAPN. Factors influencing the occurrence of RAP among these 98 patients, including the 2 who underwent emergency RAE and excluding the 2 who underwent prophylactic RAE, were analyzed by logistic regression analysis.

Results

Median [interquartile range (IOR), range] observation period, age, radiographic tumor size, and maximum diameter of RAP were 20.8 (23.9, 3.0–57.6) months, 63 (18, 22–84) years, 23 (11, 9–48) mm, and 6.6 (5.2, 3.0–16.0) mm, respectively. CE-CT detected 28 RAPs in 23 (23.0%) of 100 patients by 7 days after RAPN and routine CE-CT detected 25 RAPs in 21 (21.4%) of 98 patients excluding 2 who underwent emergency RAE at 7 days after RAPN. RAP was diagnosed by routine CE-CT in 21 (21.4%), 1 (1.0%), and 0 (0%) patients at 7 days, 1 month, and 3 months after RAPN, respectively. In univariate analysis, age [odds ratio (OR) 0.144: 69–84 vs. 22–56 years old, P=0.0179], R.E.N.A.L [radius (tumor size as maximal diameter), exophytic/endophytic properties of tumor, nearness of tumor deepest portion to collecting system or sinus, anterior/posterior descriptor and location relative to polar line] nephrometry score (OR 1.374, P=0.0382), warm ischemic time (OR 1.085, P=0.0393), and renorrhaphy time (OR 1.055, P=0.0408) were significantly associated with the occurrence of RAP. In multivariate analysis, only age (OR 0.124, P=0.0148) was a significant factor.

Conclusions

Asymptomatic RAP up to 15 mm in diameter resolved spontaneously 3 months after RAPN. Young age (under 56 years) may be a factor in the development of RAP.

Limited impact of warm ischemic threshold for partial nephrectomy in the robotic surgery era: A propensity score matching study

OBJECTIVES

To evaluate the association between extended (≥30 min) warm ischemic time and renal function in patients undergoing robot-assisted partial nephrectomy.

METHODS

This multi-institutional study retrospectively recruited 1131 patients who underwent robot-assisted partial nephrectomy. Patients were classified into shorter (<30 min; n = 1038) and longer (≥30 min; n = 92) groups based on the ischemic time required, and 1:2 propensity score matching was used to minimize selection bias. The perioperative outcomes, including acute kidney injury and trifecta attainment, and mid/long-term renal function were assessed before and after matching.

RESULTS

Patients in the longer group had tumors with a significantly larger diameter and RENAL nephrometry score. The decline in the nadir of the estimated glomerular filtration rate was significantly greater in the longer than the shorter group in the unmatched and matched cohorts (-16.2 vs -5.5%, P < 0.001; 15.5 vs -9.5%, P = 0.003, respectively). A higher incidence of acute kidney injury (9.8 vs 2.6%, P = 0.002) was observed in the longer group before matching, whereas the difference was comparable after matching. Before matching, the decline in estimated glomerular filtration rate at 6 months postoperatively was greater (-8.2 vs -5.1%, P = 0.005) and trifecta attainment was lower (50.0 vs 63.5%, P < 0.001) in the longer group. However, the differences were comparable for both the parameters between the groups in the matched cohort.

CONCLUSIONS

While extended warm ischemia during robot-assisted partial nephrectomy can be demanded in case of large and complex tumors, its impact on postoperative renal function is limited.

Test clamp procedure in robot-assisted partial nephrectomy: is it a safe procedure?

We performed test clamp procedure in robot-assisted partial nephrectomy (RAPN) to prevent massive bleeding during tumor resection and to omit dissection of non-feeding arteries around the tumor. We subsequently analyzed the safety and usefulness of the procedure. The Test clamp procedure was performed for 1 to 3 min during renal artery test ischemia prior to the actual ischemia and tumor resection. We confirmed the disappearance of blood flow around the renal tumor using color Doppler ultrasonography. If arterial blood flow around the tumor remained, we surveyed the site for other arteries that needed to be clamped and repeated the test clamp procedure until renal blood flow around the tumor disappeared. We retrospectively analyzed consecutive RAPN cases performed from July 2016 to March 2020 at our institutions and reviewed medical records. The clinical data of the RAPN cases were statistically analyzed. Sixty-four RAPN cases underwent the test clamp procedure, which was categorized as the TEST group. Test clamping was performed safely without any clamping-related complications in all cases. Eleven cases (17%) underwent partial ischemia, which was a significantly higher number than that in the control group. Massive bleeding during tumor resection was more frequent in the control group. Postoperative deterioration of estimated glomerular filtration rate did not differ significantly between both groups. Although further investigation was still necessary, our findings indicate that the test clamp procedure may be a safe and secure procedure to perform in RAPN for both patients and surgeons.

Perioperative outcomes in patients undergoing robot-assisted partial nephrectomy: Comparative assessments between complex and non-complex renal tumors

INTRODUCTION

The aim of this study was to investigate the effects of renal tumor complexity on perioperative outcomes in patients receiving robot-assisted partial nephrectomy (RAPN).

METHODS

This study included 153 consecutive patients with cT1 renal masses undergoing RAPN and analyzed their perioperative outcomes, particularly tumor complexity. In this series, cT1b, completely endophytic, hilar, and cystic tumors were considered complex tumors. Patients with tumors that met at least one of the complex criterion were placed in the complex tumor group; patients with tumors that did not meet any of the complex criteria were placed in the non-complex tumor group.

RESULTS

Of the 153 patients, 54 (35.3%) had complex tumors; specifically, 18 (11.8%) had cT1b tumors, 15 (9.8%) had completely endophytic tumors, 28 (18.3%) had hilar tumors, and 8 (5.2%) had cystic tumors. The non-complex group included 99 patients (64.7%). The complex tumor group had significantly longer warm ischemia and console times than the non-complex tumor group, but there was no significant difference between them in the achievement of the trifecta. Both warm ischemia and console times were significantly correlated with the number of complex factors. Multivariate analyses of complex factors demonstrated that completely endophytic and cT1b tumors were independently associated with warm ischemia time and console time, respectively.

CONCLUSIONS

For patients with complex tumors, RAPN may be a feasible procedure with acceptable perioperative outcomes. However, special attention should be paid to long warm ischemia and console times, particularly in those with completely endophytic and/or cT1b tumors.

Utilization of a three-dimensional printed kidney model for favorable TRIFECTA achievement in early experience of robot-assisted partial nephrectomy

Background

This retrospective study aimed to investigate whether a three-dimensional (3D) model would improve the achievement of TRIFECTA, which was defined as the absence of perioperative complications and positive surgical margins and a warm ischemia time of <25 minutes, during robot-assisted partial nephrectomy (RAPN).

Methods

Prior to RAPN, a 3D-square type kidney model was prepared and used for all RAPN procedures in patients with T1a renal cell carcinoma (RCC) treated at a single center between March 2016 and April 2019. All RAPN procedures were performed by a single surgeon.

Results

The study included 50 patients, of whom 22, 24, and 4 had low-, intermediate-, and high-risk R.E.N.A.L Nephrometry scores, respectively. The TRIFECTA achievement rate was 86.0%, and transfusion or conversion to radical nephrectomy was not required in any of the patients. Only one Clavien-Dindo grade 3 complication was reported—a pseudoaneurysm that required embolism. The TRIFECTA achievement rate was independent of the R.E.N.A.L Nephrometry scores and the surgeon’s experience level (25 cases each of early and advanced experience).

Conclusions

The 3D model contributed to the achievement of TRIFECTA during RAPN performed by a less-experienced surgeon. These findings should be further evaluated in studies involving a larger number of cases and surgeons.

Outcomes of gasless laparoendoscopic single-port partial nephrectomy in 356 consecutive patients: Feasibility of a clampless and sutureless technique

OBJECTIVES

To investigate the outcomes and feasibilities of gasless laparoendoscopic single-port clampless sutureless partial nephrectomy.

METHODS

We reviewed 356 consecutive patients with primary unilateral non-metastatic renal masses who underwent gasless laparoendoscopic single-port partial nephrectomy (2011-2018), which was performed retroperitoneally using a three-dimensional flexible endoscope, without vascular clamping or renorrhaphy in principle.

RESULTS

The median tumor size was 2.5 cm, and 213 (60%), 105 (29%), and 38 (11%) patients had peripheral, central, and hilar tumors, respectively. Clampless and sutureless partial nephrectomy was accomplished in 337 patients (95%), while eight (2%) and 16 (4%) patients required vascular clamping and renorrhaphy, respectively. The median operative time and blood loss were 220 min and 266 mL, respectively; eight patients (2%) received blood transfusion. Clavien-Dindo grade 3a complications occurred in 27 patients (8%); all these patients had urinary leakage treated with ureteral stent placement, one of whom also developed a postoperative pseudoaneurysm. Among 324 patients diagnosed with renal cell carcinoma, six (2%) had positive surgical margins, and one (0.3%) and seven (2%) developed metastatic and local recurrences, respectively. During a median follow-up of 54 months, no patient died from kidney cancer. The median percent decrease in estimated glomerular filtration rate at 3 months after surgery was 5.7%. No patient experienced postoperative acute renal failure, while one patient with preexisting renal impairment started dialysis at 70 months after surgery.

CONCLUSIONS

Clampless and sutureless partial nephrectomy can be safely accomplished in most patients undergoing gasless laparoendoscopic single-port surgery, yielding favorable oncological and functional outcomes.

Natural History of Asymptomatic Pseudoaneurysm Soon After Robot-assisted Partial Nephrectomy: Single-center Prospective Study

OBJECTIVE

To prospectively investigate the natural history of asymptomatic pseudoaneurysm after robotic-assisted partial nephrectomy.

METHODS

Robotic-assisted partial nephrectomy was undertaken for 67 patients between July 2014 and July 2018. Patients who could not undergo enhanced CT were excluded, so 60 patients were finally included in the present study. We prospectively investigated the presence of pseudoaneurysm based on early enhanced CT scan on postoperative day 7. According to our treatment policy, patients with symptomatic pseudoaneurysm underwent selective transarterial embolization. Meanwhile, patients with asymptomatic pseudoaneurysm were observed with follow-up CT imaging, regardless of the size of the aneurysm.

RESULTS

Overall incidence of pseudoaneurysm on postoperative day 7 was 18% (11/60 cases). The median size of the pseudoaneurysm was 9 mm (quartile: 6-12 mm). Two patients with symptomatic pseudoaneurysm underwent selective transarterial embolization. Nine patients had asymptomatic pseudoaneurysm; in 8 of these it disappeared without therapeutic intervention. The median period from surgery to confirmed disappearance of the aneurysm was 19 days (quartile 14-32 days). In the remaining 1 patient, small asymptomatic pseudoaneurysm (2 mm) could still be observed even 1 year after surgery.

CONCLUSION

Our study showed high incidence of pseudoaneurysm 1 week after robotic-assisted partial nephrectomy that mostly disappeared without therapeutic intervention. Routine enhanced CT screening and pre-emptive embolization may not be necessary for asymptomatic renal artery pseudoaneurysm.

Off-clamp tumor excision using soft coagulation in laparoscopic and robotic partial nephrectomy

INTRODUCTION

The aim of this study was to assess the perioperative outcomes of off-clamp tumor excision using soft coagulation in laparoscopic and robotic partial nephrectomy.

METHODS

We retrospectively analyzed the data from 78 patients who underwent minimally invasive partial nephrectomy, using soft coagulation, at the Shiga University of Medical Science, between September 2013 and April 2017. Tumor excision and hemostasis without renal arterial clamping was performed using soft coagulation. Collecting system repair and renorrhaphy with arterial clamping were carried out only if the collecting system had been opened.

RESULTS

Forty-three of the 78 patients underwent laparoscopic partial nephrectomy using soft coagulation and the other 35 patients underwent robotic partial nephrectomy using soft coagulation. The median estimated total blood loss was 73 (0-1140) mL and no patient needed a blood transfusion. No cases featured postoperative hemorrhagic events. Six patients with urinary fistula needed prolonged ureteral stenting. The median percentage change of the estimated glomerular filtration rate was -7.2 at one to 3 months after surgery.

CONCLUSION

The off-clamp soft coagulation technique in laparoscopic partial nephrectomy and robotic partial nephrectomy is a safe and feasible approach to excise kidney tumors. This procedure may reduce the incidence of perioperative hemorrhagic complications.

Mid-term outcome of transarterial embolization of renal artery pseudoaneurysm and arteriovenous fistula after partial nephrectomy screened by early postoperative contrast-enhanced CT

Purpose

To retrospectively evaluate the mid-term outcome of transarterial embolization (TAE) of renal artery pseudoaneurysm (RAP) including arteriovenous fistula (AVF) after partial nephrectomy screened by early postoperative contrast-enhanced CT (CE-CT).

Materials and methods

Eighty-two patients (7.0%) who underwent TAE after partial nephrectomy were reviewed, from 1166 partial nephrectomies performed over 6 years. In 18 patients (22.0%), TAE was performed emergently on the median postoperative day (POD) seven. In the remaining patients, elective TAE was performed on the median POD six for RAP detected by early postoperative CE-CT or that emerged on follow-up CE-CT.

Results

In one patient (1.2%), TAE was performed twice because one of two RAPs could not be embolized during the first TAE, being successfully embolized at the second TAE after readmission with hematuria. Otherwise, no bleeding recurrence or RAPs were observed during the median 1354 follow-up days. Thus, the primary and secondary success rates of TAE were 98.8% (81 of 82 patients) and 100% (82 of 82 patients), respectively. On angiography, the average number of lesions was 1.7 ± 0.9 and the average RAP size was 12.8 ± 6.0 mm. The shapes of the lesions varied: oval-round 60, oval-round + AVF 36, irregular + AVF 14, AVF 12, irregular 10, disruption 4, and extravasation 3. No major complications were observed. The median inpatient days after TAE were two. No estimated glomerular filtration rate deterioration was observed (64.6 ± 18.6 vs. 64.2 ± 18.4 mL/min/1.73 m², p = 0.902).

Conclusion

TAE is largely effective and safe for treating bleedings or RAPs, including AVFs, after partial nephrectomy, as screened by early postoperative CE-CT.

Lower Incidence of Postoperative Acute Kidney Injury in Robot-Assisted Partial Nephrectomy Than in Open Partial Nephrectomy: A Propensity Score-Matched Study

Background: Acute kidney injury (AKI) after partial nephrectomy is attributed to parenchymal reduction and ischemia, but the extent of its effect remains unclear. This study aimed to compare the incidence of postoperative AKI among surgical modalities, robot-assisted partial nephrectomy (RAPN), laparoscopic partial nephrectomy (LPN), and open partial nephrectomy (OPN), and to evaluate the validity of RAPN by comparing it with LPN and OPN in terms of postoperative AKI, perioperative complications, and long-term renal function. Patients and Methods: Patients who underwent RAPN, LPN, and OPN for renal tumors at our institutions between 2004 and 2018 were retrospectively analyzed. RAPN and LPN were performed under warm ischemia and OPN under cold ischemia. En bloc hilar clamping was employed for LPN and OPN and arterial clamping for RAPN. AKI was defined as % decrease in estimated glomerular filtration rate (eGFR) >25% from preoperative eGFR to postoperative nadir eGFR. Multivariate regression analysis was used to test associations of AKI with perioperative factors. Then, we compared the incidence of AKI with two propensity score-matched cohorts: RAPN vs OPN and RAPN vs LPN. Results: This study included 1762 cases (RAPN: 959, LPN: 215, and OPN: 588). After matching, 147 cases each from RAPN and LPN groups and 368 cases each from RAPN and OPN groups were selected. RAPN had shorter warm ischemia time than LPN, lower incidence of AKI, and lower % decrease in eGFR after 6 months. RAPN had a shorter ischemia time and a lower incidence of AKI than OPN, although the % decrease in eGFR after 6 months did not differ significantly. Conclusions: AKI incidence was lower in RAPN than in LPN or OPN, which may be due to the shorter ischemia time or clamping of only arteries in RAPN. Although long-term renal outcomes did not differ between RAPN and OPN, RAPN can help prevent AKI. This supports the validity of RAPN for patients with chronic kidney disease.

Omitting Cortical Renorrhaphy in Robot-Assisted Partial Nephrectomy: Is it Safe? A Single Center Large Case Series

Introduction: Preserving renal function after robot-assisted partial nephrectomy (RAPN) is important and influenced by the technique of renal reconstruction among other parameters, including ischemia time and amount of healthy renal tissue resected. It is believed that reconstruction with a second layer of cortical renorrhaphy is necessary to prevent urinary leaks and postoperative bleeding, but this is associated with the potential loss of healthy renal parenchyma and may result in worse outcomes postoperatively. Purpose: To assess the safety of omitting cortical renorrhaphy during RAPN. Patients and Methods: A retrospective analysis of 146 consecutive patients undergoing a RAPN with single or double layer renorrhaphy at the Wirral University Teaching Hospital from 2014 to 2019. Data obtained included: Patient demographics, tumor RENAL nephrometry, Perioperative parameters; blood loss, duration, and warm ischemia time (WIT), Postop complications, change in estimated glomerular filtration rate (eGFR) (pre and 3 months postop), length of stay, and oncologic outcomes. Results: In total 146 patients were identified. One hundred-six had double renorrhaphy and 40 inner layer only renorrhaphy. No significant differences were seen between these two cohorts in terms of patient demographics, RENAL nephrometry score, tumor size, or location. Perioperative parameters showed a reduced duration of surgery in the single renorrhaphy group with a mean of 125 minutes compared to143 minutes in the double renorrhaphy (p = 0.006) and a tendency toward a shorter WIT of 12.9 minutes vs 14.0 minutes reaching borderline statistical significance (p = 0.05) but no difference in blood loss volume (p = 0.25). Postoperatively there was no statistical difference in the length of hospital stay (p = 0.85), loss in eGFR at 3 months (0.06), or complication (p = 0.56). After a median follow-up of 35 months no recurrences or deaths were observed in either group. Conclusions: Omission of cortical renorrhaphy appears feasible and safe with no urine leaks or excess complications observed.

Initial learning curve for robot-assisted partial nephrectomy performed by a single experienced robotic surgeon

INTRODUCTION

The objective of this study was to evaluate the initial learning curve for robot-assisted partial nephrectomy (RAPN) using the da Vinci Xi Surgical System (Intuitive Surgical, Sunnyvale, California).

METHODS

This study included the initial 65 consecutive patients with small renal tumors who had undergone RAPN at our institution. A single trained surgeon with extensive experience in robot-assisted radical prostatectomy, but not in laparoscopic partial nephrectomy, performed RAPN for all patients using the da Vinci Xi. The learning curve was analyzed by examining the perioperative outcomes among five groups each consisting of 13 consecutive patients.

RESULTS

In this series, the median tumor size and R.E.N.A.L. nephrometry score were 23 mm and 7, respectively, and the median console time and warm ischemia time (WIT) were 116 and 15 minutes, respectively. Fifty-eight patients (89.2%) achieved trifecta outcomes, meaning that the ischemic time was ≤25 minutes, there was a negative surgical margin, and no major postoperative complications occurred. Although there were no significant changes in R.E.N.A.L. nephrometry scores over time, increased surgeon experience was significantly associated with a shorter console time and WIT. Drawing logarithmic approximation curves enabled the achievement of a console time ≤150 minutes and WIT ≤20 minutes at the sixth and fourth procedures, respectively. Furthermore, multivariate analysis identified an independent correlation between surgeon experience with WIT, but not with console time.

CONCLUSION

These findings suggest that regardless of a surgeon's prior experience in laparoscopic partial nephrectomy, an experienced robotic surgeon can perform RAPN using the da Vinci Xi with acceptable perioperative outcomes after a small number of procedures.

Significant impact of three-dimensional volumetry of perinephric fat on the console time during robot-assisted partial nephrectomy

Background

To assess the impact of volumetry of perinephric fat (PNF) on the perioperative outcomes of robot-assisted partial nephrectomy (RAPN).

Methods

Between 2016 and 2019, a single surgeon performed RAPN for 128 patients with clinical T1a-b renal tumors at our institution, and the 70 most recent patients were included in this study to minimize the effects of surgical experience. PNF was defined as a fatty area around the kidney within the anatomical structures, including the lateroconal fascia, fusion fascia, psoas muscle, lumbar quadrate muscle and diaphragm, and its volume was calculated based on reconstructed three-dimensional computed tomography images using the SYNAPSE VINCENT system.

Results

In this series, the trifecta and MIC (margin, ischemia and complications) score system outcomes were achieved in 69 (98.6%) and 64 patients (91.4%), respectively. The median PNF volume in the 70 patients was 166.05 cm³, which was significantly correlated with both the body mass index (BMI) and Mayo adhesive probability (MAP) score (correlation coefficient = 0.68 and 0.74, respectively). There was no significant difference in the R.E.N.A.L. nephrometry score, PNF volume or console time during RAPN among 5 groups consisting of 14 consecutive patients. Of several factors examined, the console time was significantly affected by the sex, MAP score and PNF volume, and only the PNF volume was independently associated with the console time.

Conclusion

Even if performed by an experienced robotic surgeon beyond the initial learning curve, the PNF volume may influence the console time during RAPN.

The efficacy of the TachoSil binding suturing technique in laparoscopic partial nephrectomy to prevent the development of pseudoaneurysm

OBJECTIVE

Our specific aim was to introduce the TachoSil binding suturing technique for renal cell carcinoma (RCC) patients when closing the parenchymal defect after tumor excision during laparoscopic partial nephrectomy (LPN), which is a novel technique for reducing the risk of developing subsequent pseudoaneurysm (PA).

METHODS

We identified 113 pT1aN0M0 RCC patients who underwent LPN at our institution. Eighty-one (72%) patients underwent the suturing procedure without binding TachoSil, whereas 32 (28%) patients underwent renorraphy with the renal defect closed together with TachoSil. The vascular complications were evaluated by computed tomography or magnetic resonance imaging with enhanced contrast material at the first visit after LPN. We conducted Fischer's exact test to determine risk factors for transcatheter arterial embolization (TAE).

RESULTS

The median age was 55 (36-86) years old and the median follow-up time was 65 (12-147) months. In the overall population, there were 11 (11%) patients who underwent TAE because they developed PA. All 11 patients exhibited the imaging findings of PA, and were all from the conventional suturing group. In contrast, no patients for whom the TachoSil binding method was used had any significant findings on imaging (14% vs. 0%). Based on the analysis to determine risk factors for TAE due to PA development, the TachoSil binding suturing technique was one of the significant indicators for reducing the risk of developing PA.

CONCLUSIONS

Our study demonstrated that the TachoSil binding suturing technique might reduce the development of PA after LPN. Prospective randomized study and comparison to the standard 2 or 3-layer renorrhaphy is needed to prove its actual value.

Postoperative Complications After Robotic Partial Nephrectomy

Objectives: To assess the incidence of postoperative arterial malformation (AM) and urine leak/urinoma (UL) after robotic partial nephrectomy (RPN) in a contemporary series and to evaluate risk factors for these complications. Materials and Methods: All RPNs were queried from Institutional Review Board-approved retrospective and prospective nephrectomy databases. Demographics, perioperative variables, and postoperative complications were collected. Differences between cohorts were analyzed using univariate analysis. Postoperative complications were graded using the Clavien-Dindo system. UL was defined in the context of signs and symptoms of a collection with supporting evidence of urine collection through drainage or aspiration. AM was identified based on postoperative imaging indicative of arteriovenous fistula or pseudoaneurysm and/or requirement for selective embolization. Predictors of AM and UL were assessed by univariate analysis. Results: A total of 395 RPNs were performed by four urologists between January 2014 and October 2018. Tumor complexity, defined by nephrometry score, was significantly greater in the prospective cohort (p = 0.01). Overall incidence of postoperative complications was 5.6% with cohort-specific incidences of 5.3% and 5.8%. The retrospective cohort had a greater percentage of complications classified as ≥IIIa: 8/13 (61.5%) vs 2/8 (25%). Overall incidence of AM was 2.3% with cohort-specific incidence of 3.1% (7/225) vs 1.1% (2/170). Overall incidence of UL was 0.25% with cohort-specific incidence of 0.55% (1/225) and 0.0% (0/170). The difference in incidence of both complications between cohorts was significant (p < 0.05). No significant predictors for AM were identified. Conclusions: The incidence of postoperative complications after RPN remains low (5.3% vs 5.8%, overall: 5.6%). UL and AM are becoming rarer with experience, despite increasing surgical complexity (0.55% vs 0%, 3.1% vs 1.1%).

Performing an early systematic Doppler-ultrasound fails to prevent hemorrhagic complications after complex partial nephrectomy

Background:

The aim of this work was to assess the clinical relevance of a systematic postoperative Doppler-ultrasound (DU) after complex partial nephrectomy (PN).

Materials and methods:

All patients who underwent open, laparoscopic or robotic PN from 2014 to 2017 at our institution were included. Postoperative hemorrhagic complications (HCs) were defined as the occurrence of blood transfusion, hemorrhagic shock, arterial embolization, or re-hospitalization for hematoma. DU was systematically performed between post-op day 4 and 7 for every complex tumor (RENAL score ⩾ 7). DU was considered positive in the presence of pseudoaneurysm (PA) or arteriovenous fistula (AVF).

Results:

Among 194 patients, 117 underwent DU (60.3%). We reported 22 HCs (11.3%) requiring 8 selective embolization procedures (4.1%). HCs occurred during the hospital stay in 17 patients (77.3%), thus directly diagnosed on a computed tomography scan. Among the five patients (22.7%) with HC occurring after hospital discharge, between day 7 to 15, four had a previously negative systematic DU. Overall, systematic DU was positive in only five patients (4.3%) with only one patient of 194 (0.5%) undergoing preventive embolization of a PA-AVF. The negative predictive values (NPVs) and positive predictive values of DU were respectively 96.5% and 5%, with 20% sensitivity and 96.5% specificity.

Conclusions:

Our results may suggest offering systematic DU in patients under antiplatelet therapies, with high tumor size (>T1b), or early postoperative hemoglobin variations. A high NPV of DU might be counterbalanced by its low sensibility. Since all secondary HCs occurred between postoperative day 7 to 15, our results may suggest differing DU in selected cases.

Improved perioperative outcomes by early unclamping prior to renorrhaphy compared with conventional clamping during robot-assisted partial nephrectomy: a propensity score matching analysis

The objective of this study was to evaluate the impact of the early unclamping (EU) technique on perioperative outcomes in patients who underwent robot-assisted partial nephrectomy (RAPN). This study included 96 patients with small renal masses who underwent RAPN performed by a single surgeon using the da Vinci Xi between April 2016 and September 2018. EU and conventional clamping (CC) procedures were defined as those removing the renal artery clamp before and after renorrhaphy, respectively. In this series, contrast-enhanced computed tomography was performed 3-5 days after RAPN to examine the incidence of renal artery pseudoaneurysm (RAP). After adjusting patient variables by 1:1 propensity score matching, 45 patients were included in both the EU and CC groups, and no significant differences in major clinical characteristics were noted between these two groups. Although there was no significant difference in the proportion of patients achieving trifecta or the margin, ischemia and complications score between the two groups, the EU group was significantly superior to the CC group regarding the operative time, console time, warm ischemia time, impairment of renal function 1 day after RAPN, incidence of RAP and postoperative length of hospital stay. Furthermore, RAP occurred in seven patients in the entire cohort (13.3%) receiving CC, including two who required trans-arterial embolization due to severe macrohematuria, whereas RAP was completely prevented by the use of EU. The introduction of the EU technique to RAPN may improve perioperative outcomes, particularly by markedly reducing the risk of RAP even with renorrhaphy.

Comparison of perioperative outcomes with or without renorrhaphy during open partial nephrectomy: A propensity score-matched analysis

Purpose:

Renorrhaphy in partial nephrectomy may damage intraparenchymal vessels and compress the renal parenchyma, which may lead to the formation of renal artery pseudoaneurysms or vascularized parenchymal volume reduction. Using propensity score matching, we compared surgical outcomes following non-renorrhaphy and renorrhaphy techniques for open partial nephrectomy (OPN) for T1a renal tumors.

Materials and Methods:

We retrospectively analyzed data from 159 patients with normal contralateral kidneys who underwent OPN for T1a renal tumors and pre- and postoperative enhanced computed tomography between 2012 and 2015. Patient variables were adjusted using 1:1 propensity score matching between the two Groups: renorrhaphy (inner and outer layer sutures) and non-renorrhaphy (inner layer sutures only). Postoperative complications and renal function were compared between the two groups.

Results:

We matched 43 patients per Group. Operative time, estimated blood loss, cold ischemic time, and postoperative hospital stay were not significantly different between the two Groups. Urine leakage (Clavien-Dindo grade ≥3) occurred in 0 renorrhaphy cases and 2 non-renorrhaphy cases (0% versus 4.6%, P=0.49). Renal artery pseudoaneurysm (RAP) occurred in 6 renorrhaphy cases and in 0 non-renorrhaphy cases (13% versus 0%, P=0.02).

Conclusions:

The non-renorrhaphy technique may result in a lower risk of RAP but a greater risk of urine leakage. This technique needs further refinement to become a standard procedure for OPN.

Simplified robot-assisted partial nephrectomy: step-by-step technique and perioperative outcomes

Controversies have been raised and still exist regarding several technical aspects of robot-assisted partial nephrectomy (RAPN). While the "perfect RAPN" has still to be determined, we aimed to report a simplified technique of RAPN in a step-by-step fashion and the perioperative outcomes of a single-center series. A simplified technique of RAPN was developed, refined and standardized over the past 7 years in an academic department of urology to make it as safe and as reproducible as possible, the main goal being to make it an "easy to learn" technique for fellows. This technique is presented in 12 key steps. The patients' characteristics and perioperative outcomes were prospectively collected and are reported herein. Since the first case performed in our department in 2010, 406 patients have undergone RAPN with a standardized and stable simplified technique after the first 30 cases, involving several key steps including systematic use of the transperitoneal approach, minimal visceral mobilization of the colon, systematic psoas exposure and ureter identification, minimal dissection of the perinephric fat, arterial clamping with early unclamping, no use of hemostatic agents or drain. The majority of RAPN were performed by surgeons with either low experience (i.e., < 20 procedures; 46.3%) or intermediate experience (i.e., 20-50 procedures; 17.2%). The mean warm ischemia time was 15.3 min. Conversions to an open approach and to radical nephrectomy were required in 14 (3.5%) and 21 (5.2%) cases, respectively. From 132 patients who experienced post-operative complications (32.5%), 47 experienced a major complication (11.6%). The positive surgical margin rate was 5.6%. The simplified technique of RAPN was feasible and reproducible with satisfactory perioperative outcomes. Most of the key steps have been assessed through single-center and multicenter clinical studies.

Comparison of Kidney Function in the Early Postoperative Period in Transperitoneal Robot-Assisted Laparoscopic Partial Nephrectomy Between Anterior and Posterior Renal Tumors: A Propensity Score-Matched Study

OBJECTIVE

To compare early postoperative renal function in transperitoneal robot-assisted laparoscopic partial nephrectomy (RAPN) for anterior and posterior renal tumors.

PATIENTS AND METHODS

This study included 227 patients who underwent transperitoneal RAPN for anterior or posterior renal tumors. Tumor position was defined by RENAL nephrometry score. To minimize selection bias between anterior and posterior tumors, patient variables were adjusted using 1:1 propensity score matching.

RESULTS

Of the 227 patients, 125 were classified as having anterior tumors and 102 as having posterior tumors. After matching, 82 patients were included in each group. The mean preoperative estimated glomerular filtration rate (eGFR) was 66 mL/min/1.73 m². The mean tumor size was 28 to 29 mm. The decrease in early postoperative nadir eGFR (-10% vs -4.0%, p = 0.0103) was significantly higher for posterior tumors than for anterior tumors. However, the difference improved 6 to 12 months after surgery (-6.0% vs -6.2%, p = 0.9564). The other surgical outcomes, including operative time, warm ischemia time (WIT), complications, surgical margin status, and length of hospital stay, were not significantly different between the two groups. In multivariate analysis of the entire cohort, posterior tumors (vs anterior tumor, odds ratio [OR]: 2.30, p = 0.0051), longer WIT (OR: 3.10, p = 0.0019), and high tumor complexity (vs low complexity, OR: 3.46, p = 0.0264) were independent predictors for development of a 10% decrease in early postoperative eGFR.

CONCLUSIONS

Posterior tumors had a greater decrease in early postoperative nadir eGFR than anterior tumors, with equivalent surgical outcomes, including similar renal function, 6 to 12 months after surgery in the setting of transperitoneal RAPN.

Laparoscopic Partial Nephrectomy: A Narrative Review and Comparison with Open and Robotic Partial Nephrectomy

INTRODUCTION

Kidney cancer ranks among the top 10 most prevalent cancers in Western society, ∼90% of which are renal cell carcinomas. There has been a paradigm shift in the management of small renal masses with strong emphasis now placed on nephron-sparing surgery and increased utilization of laparoscopic approaches to partial nephrectomy. In this review, the current state of laparoscopic partial nephrectomy (LPN) is discussed.

EVIDENCE ACQUISITION

The PubMed database was queried using the MeSH terms "laparoscopy" and "nephrectomy," as well as the search term "partial." A search was performed filtering for "clinical trial," "review," "humans", and "English."

EVIDENCE SYNTHESIS

Articles that discussed intraoperative techniques, functional and oncologic outcomes, and a comparison between robot-assisted partial nephrectomy and LPN were synthesized.

CONCLUSION

LPN reduces ischemia time, affords equivalent functional outcomes, oncologic outcomes, and equivalent complication rates compared with open partial nephrectomy. Future advances in laparoscopic technique and advancements in robotic technology offer potential to improve surgical and patient outcomes.