Reevaluating Warm Ischemia Time as a Predictor of Renal Function Outcomes After Robotic Partial Nephrectomy

The effect of 11th rib excision on perioperative outcomes in patients undergoing partial nephrectomy for upper pole renal tumors

INTRODUCTION

We aimed to evaluate the effect of eleven11th rib resection.on the perioperative period TRIFECTA criteria in patients who underwent retroperitoneal partial nephrectomy (PN) with the diagnosis of upper pole kidney tumors.

MATERIALS AND METHODS

We conducted a retrospective analysis of the data of the patients who underwent Open PN for upper pole renal masses between 2018 and 2023. The patients were divided into two groups: PN with rib resection and PN without rib resection. The demographic characteristics, tumor sizes, PADUA scores, warm-cold renal ischemia times, mass excision and tumor bed suturing times, histopathological tumor type and surgical margin positivity of the patients were examined. Both groups were evaluated comparatively based on this data.

RESULTS

The renal nephrometry scores of the two groups were similar. The total renal ischemia time was significantly shorter in the patients who underwent a rib resection than in those who did not (p < 0.001). Both the tumor excision and tumor bed suturing times were significantly shorter in the group that underwent a rib resection than in the group that did not (p < 0.001). The Clavien-Dindo complication grades were statistically similar between the two groups.

CONCLUSION

Complex in nature and high-risk renal masses located in the upper pole of the kidney, partial nephrectomy performed with an 11th rib resection can be considered a reliable surgical option with a shorter ischemia time, supporting the preservation of long-term renal function.

Impact of tumor dissecting technique on trifecta achievement in patients requiring extended warm ischemia during robot-assisted partial nephrectomy

PURPOSE

To clarify specific factors associated with surgical outcomes in robot-assisted partial nephrectomy (RAPN) that require extended warm ischemia time (WIT), which may have a negative impact, but cannot always be avoided.

METHODS

We included 1,182 patients who had RAPN performed between January 2016 and December 2022 from a prospectively generated multi-institutional RAPN database, divided into normal WIT (nWIT) (≤ 20 min; 843 patients) and extended WIT (eWIT) (> 20 min; 339 patients) groups. Primary outcome measures were WIT and the Surface-Intermediate-Base (SIB) margin score, which contribute to postoperative trifecta achievement. Results were compared between the two groups using logistic regression.

RESULTS

Patients in the eWIT group had larger tumors, higher RENAL nephrometry scores, and lower SIB scores than those of the nWIT group. The trifecta achievement rate was significantly different between the two groups (nWIT: 70.1 vs. 49.0%, p < 0.001). In the nWIT group, WIT (coefficient: -0.105 [standard error 0.020], p < 0.001) and SIB score (coefficient: -0.107 [0.053], p = 0.045) were significant predictors of trifecta achievement. In the eWIT group, the SIB score (coefficient - 0.216 [0.082], p = 0.008) was significantly associated with trifecta attainment, whereas WIT only showed a trend toward significance. Limitations included a lack of long-term survival, renal function, and chronic complications data.

CONCLUSIONS

For patients with eWIT during RAPN, the tumor dissection technique may be more important than WIT in predicting postoperative outcomes. Further prospective studies are required to confirm our results.

Renal and major clinical outcomes and their determinants after nephrectomy in patients with pre-existing chronic kidney disease: A retrospective cohort study

The consequences of partial nephrectomy (PN) compared to radical nephrectomy (RN) are less documented in patients with pre-existing chronic kidney disease (CKD) or with solitary kidney (SK). We assessed renal outcomes, and their determinants, after PN or RN in a retrospective cohort of patients with moderate-to-severe CKD (RN-CKD and PN-CKD) or SK (PN-SK). All surgical procedures conducted between 2013 and 2018 in our institution in patients with pre-operative estimated glomerular filtration rate (eGFR)<60 mL/min/1.73m2 or with SK were included. The primary outcome was a composite criterion including CKD progression or major adverse cardio-vascular events (MACE) or death, assessed one year after surgery. Predictors of the primary outcome were determined using multivariate analyses. A total of 173 procedures were included (67 RN, and 106 PN including 27 SK patients). Patients undergoing RN were older, with larger tumors. Preoperative eGFR was not significantly different between the groups. One year after surgery, PN-CKD was associated with lower rate of the primary outcome compared to RN-CKD (43% vs 71% p = 0.007). In multivariate analysis, independent risk factors for the primary outcome were postoperative AKI (stage 1 to stage 3 ranging from OR = 8.68, 95% CI 3.23-23.33, to OR = 28.87, 95% CI 4.77-167.61), larger tumor size (OR = 1.21 per cm, 95% CI 1.02-1.45), while preoperative eGFR, age, sex, diabetes mellitus, and hypertension were not. Postoperative AKI after PN or RN was the major independent determinant of worse outcomes (CKD progression, MACE, or death) one year after surgery.

Predictive factors of renal function after robot-assisted partial nephrectomy in clinical T1b tumors

Robot-assisted partial nephrectomy (RAPN) has been shown to be a safe and effective method for treatment of small renal tumors, including clinical T1b renal cell carcinoma (RCC); however, the impact of RAPN for cT1b renal tumors on renal function is not well understood. In this retrospective study, 50 patients who underwent RAPN for cT1b renal tumors were evaluated for pre- and post-operative renal function and perioperative clinical factors. Renal function was assessed using the estimated glomerular filtration rate (eGFR) at baseline and on postoperative days (POD) 1, 7, 30, and 180.A significant renal functional decline was defined as ≥ 15% reduction in eGFR at POD180 compared with eGFR at baseline. Logistic regression analyses were used to identify risk factors for renal function decline, including age, sex, RENAL nephrometry score, operative time, and estimated blood loss. The median patient age was 62 years, and the median tumor diameter and RENAL nephrometry score were 44 mm (IQR 43-50) and 8 (IQR 7-9), respectively. Of these patients, 16 (36%) showed a significant renal functional decline at POD 180. In the multivariate analysis, the L component of the RENAL nephrometry score and an estimated blood loss of 200 mL or more were identified as significant risk factors for renal functional decline. These findings suggest that the preoperatively definable L component of the RENAL nephrometry score and intraoperative blood loss, which may be modifiable factors, play significant roles in post-RAPN renal function decline.

Off-clamp vs on-clamp robot-assisted partial nephrectomy: a systematic review and meta-analysis

OBJECTIVE

To compare intra- and postoperative outcomes between off-clamp and on-clamp robot-assisted partial nephrectomy (RAPN), using data from randomised controlled trials (RCTs) or covariate-matched studies (propensity score-matched or matched-pair analysis).

METHODS

A Preferred Reporting Items for Systematic Reviews and Meta-Analyses-compliant literature review was conducted on PubMed, EMBASE, Scopus and CENTRAL for relevant studies comparing off-clamp to on-clamp RAPN. Primary outcomes were estimated blood loss, postoperative percentage decrease in estimated glomerular filtration rate (eGFR), and margin positive rate. Secondary outcomes were operative time, postoperative eGFR, length of stay, all postoperative complications, major complications, and need for transfusion. Random-effects meta-analyses were performed to generate mean differences (MDs) or odds ratios (ORs).

RESULTS

A total of 10 studies (2307 patients) were shortlisted for analysis. There was no significant difference in estimated operative blood loss between off-clamp and on-clamp RAPN (MD 21.9 mL, 95% confidence interval [CI] -0.9 to 44.7 mL; P = 0.06, I2  = 58%). Off-clamp RAPN yielded a smaller postoperative eGFR deterioration (MD 3.10%, 95% CI 1.05-5.16%; P = 0.008, I2  = 13%) and lower odds of margin positivity (OR 0.62, 95% CI 0.40-0.94; P = 0.03, I2  = 0%). No significant differences were found for all secondary outcomes.

CONCLUSIONS

Off-clamp and on-clamp RAPN are similarly effective approaches for selected renal masses. Within the classic trifecta of PN outcomes, off-clamp RAPN yields similar rates of perioperative complications and may possibly offer better preservation of renal function and reduced margin-positive rates.

The Association of Ischemia Type and Duration with Acute Kidney Injury after Robot-Assisted Partial Nephrectomy

BACKGROUND

Acute kidney injury (AKI) after robot-assisted partial nephrectomy (RAPN) is a robust surrogate for chronic kidney disease. The objective of this study was to evaluate the association of ischemia type and duration during RAPN with postoperative AKI.

MATERIALS AND METHODS

We reviewed all patients who underwent RAPN at our institution since 2011. The ischemia types were warm ischemia (WI), selective artery clamping (SAC), and zero ischemia (ZI). AKI was defined according to the Risk Injury Failure Loss End-Stage (RIFLE) criteria. We calculated ischemia time thresholds for WI and SAC using the Youden and Liu indices. Logistic regression and decision curve analyses were assessed to examine the association with AKI.

RESULTS

Overall, 154 patients met the inclusion criteria. Among all RAPNs, 90 (58.4%), 43 (28.0%), and 21 (13.6%) were performed with WI, SAC, and ZI, respectively. Thirty-three (21.4%) patients experienced postoperative AKI. We extrapolated ischemia time thresholds of 17 min for WI and 29 min for SAC associated with the occurrence of postoperative AKI. Multivariable logistic regression analyses revealed that WIT ≤ 17 min (odds ratio [OR] 0.1, p < 0.001), SAC ≤ 29 min (OR 0.12, p = 0.002), and ZI (OR 0.1, p = 0.035) significantly reduced the risk of postoperative AKI.

CONCLUSIONS

Our results confirm the commonly accepted 20 min threshold for WI time, suggest less than 30 min ischemia time when using SAC, and support a ZI approach if safely performable to reduce the risk of postoperative AKI. Selecting an appropriate ischemia type for patients undergoing RAPN can improve short- and long-term functional kidney outcomes.

Radiofrequency-assisted, laparoscopic, clampless partial nephrectomy in patients with low-complexity small renal tumors: A retrospective cohort study

Background

This single-center, retrospective study was performed to investigate the safety and efficacy of radiofrequency-assisted (RF), laparoscopic partial nephrectomy (PN) with zero ischemia in patients with low-complexity small renal tumors.

Materials and Methods

Patients with small renal masses (SRMs) who underwent laparoscopic, clampless laparoscopic partial nephrectomy - radiofrequency assisted (LPN-RFA) between January 2016 and June 2020 were studied. Demographics, clinical and pathological characteristics, recurrence-free survival, and overall survival were recorded.

Results

Fifty-two SRMs were excised from corresponding patients using RFA-LPN. The median tumor size was 2.5 cm and all specimens involved low-complexity masses according to the renal nephrometry score. No conversions to radical nephrectomy were recorded. Postoperatively, there were one patient with fever, one with hematuria, and two with urinary leakage treated endoscopically. The majority of tumors (48/52, 86.2%) were clear-cell carcinomas. According to the glomerular filtration rate postoperatively and 12 months' posttreatment, adequate renal function was preserved in all patients. There were no positive surgical margins identified postoperatively and no recurrences during a median follow-up 24 months. All patients were alive at the last follow-up.

Conclusions

This study suggests that RFA laparoscopic clampless PN represents an effective method for managing patients with low-complexity SRMs. It offers adequate intraoperative safety and excellent mid-term oncological control and functional preservation.

Comparison of perioperative outcomes of robotic vs. laparoscopic partial nephrectomy for renal tumors with a RENAL nephrometry score ≥7: A meta-analysis

Introduction

To compare the perioperative outcomes of robotic partial nephrectomy (RPN) vs. laparoscopic partial nephrectomy (LPN) for complex renal tumors with a RENAL nephrometry score ≥7.

Methods

We searched PubMed, EMBASE and the Cochrane Central Register for studies from 2000 to 2020 to evaluate the perioperative outcomes of RPN and LPN in patients with a RENAL nephrometry score ≥7. We used RevMan 5.2 to pool the data.

Results

Seven studies were acquired in our study. No significant differences were found in the estimated blood loss (WMD: 34.49; 95% CI: −75.16–144.14; p = 0.54), hospital stay (WMD: −0.59; 95% CI: −1.24–0.06; p = 0.07), positive surgical margin (OR: 0.85; 95% CI: 0.65–1.11; p = 0.23), major postoperative complications (OR: 0.90; 95% CI: 0.52–1.54; p = 0.69) and transfusion (OR: 0.72; 95% CI: 0.48–1.08; p = 0.11) between the groups. RPN showed better outcomes in the operating time (WMD: −22.45; 95% CI: −35.06 to −9.85; p = 0.0005), postoperative renal function (WMD: 3.32; 95% CI: 0.73–5.91; p = 0.01), warm ischemia time (WMD: −6.96; 95% CI: −7.30–−6.62; p &lt; 0.0001), conversion rate to radical nephrectomy (OR: 0.34; 95% CI: 0.17 to 0.66; p = 0.002) and intraoperative complications (OR: 0.52; 95% CI: 0.28–0.97; p = 0.04).

Discussion

RPN is a safe and effective alternative to LPNs for or the treatment of complex renal tumors with a RENAL nephrometry score ≥7 with a shorter warm ischemic time and better postoperative renal function.

Impact of ischemia time during partial nephrectomy on short- and long-term renal function

OBJECTIVE

Partial nephrectomy is the gold standard treatment in small renal tumours. During partial nephrectomy, the renal artery is clamped which creates transient ischemia. This can damage nephrons and may affect kidney function immediately postoperatively and on long-term.In the present study, we investigated the effect of ischemia time during partial nephrectomy with regards to affection of renal function immediately post-operatively and 1-year post-surgery.

MATERIALS AND METHOD

A retrospective cohort study including 124 patients who underwent partial nephrectomy at a single regional hospital in the period from 2018 to 2020 was conducted.

RESULTS

We divided patients into subgroups based on the ischemia time: [0-8], [9-13] and [14-29] minutes. The mean value for kidney function was an eGFR (mL/min) of 73.9 before and 66.8 at a 12-month post-surgery. We found no significant correlation between ischemia time and renal function. Noticeably, none of the patients had ischemia time greater than 30 min.

CONCLUSION

In this cohort, the duration of ischemia time was not associated with differences in renal affection neither on short term nor long term parameters if the ischemia time was kept below 30 min.

Moving away from mannitol infusion for partial nephrectomy: has this altered renal function?

In recent years, research has questioned the theorized renal-protective value of mannitol infusion during partial nephrectomy. This study considers whether the cessation of routine mannitol administration has shown any benefit or detriment to patients in the contemporary era. We retrospectively reviewed a multi-institution database for an association between mannitol administration and subsequent renal function during follow-up. These patients were assessed for de novo stage III chronic kidney disease (CKD III) and followed with estimated glomerular filtration rate (eGFR). Statistical analysis included Mann-Whitney-U and Chi-squared tests for comparing baseline and perioperative variables with postoperative outcomes. eGFR changes were evaluated with a mixed-effects linear regression model. Nine hundred and fifteen patients were identified whose operative reports or surgeons' treatment algorithms explicitly described whether or not mannitol was administered. 667 (73%) did not receive mannitol. There were no differences in demographics, age, Charlson comorbidity index, nephrometry score, tumor size, grading, or baseline eGFR from those who received mannitol. Ischemia time and operative time appeared slightly longer with mannitol use. Patients were followed for a median of 5 months (IQR 0.5-19 months), during which mannitol use was associated with an increase in de novo CKD III (14% v. 9%, p = 0.041) and minimally worsened median eGFR on final follow-up (72.82 v. 76.06, p = 0.039). Our analysis of partial nephrectomy patients indicates that mannitol administration likely confers no short- or long-term renal benefit. Mannitol may be used at the surgeon's discretion, but if it prolongs surgery time or ischemia time, it may in fact be detrimental to outcomes.

Identification of predictive factors for outcomes after robot-assisted partial nephrectomy based on three-dimensional reconstruction of preoperative enhanced computerized tomography

Background

Information from the RENAL score is limited. This study aimed to identify new parameters based on three-dimensional (3D) reconstruction of preoperative enhanced computerized tomography (CT) for predicting outcomes after robot-assisted partial nephrectomy (RPN).

Materials and methods

The records of kidney cancer patients who underwent RPN at Tongji Hospital from March 2015 to July 2019 were reviewed. Demographic data, laboratory examinations, postoperative hospitalization time, and enhanced CT were retrospectively collected. Some tumor parameters were obtained from 3D reconstruction of CT data. The association between these predictive factors and outcomes after RPN was analyzed.

Results

A larger tumor bed area (TBA) was associated with a longer warm ischemia time (WIT) (P-value <0.001) and tumor resection time (P-value <0.001). Moreover, TBA was significantly associated with the elevation of postoperative creatinine (P-value = 0.005). TBA (P = 0.008), distance from the tumor to the first bifurcation of the renal artery (DTA) (P <0.034), and RENAL score (P = 0.005) were significantly associated with WIT in univariate logistic regression. In multivariate logistic regression, TBA (P = 0.026) and DTA (P = 0.048) were independent risk factors for prolonged WIT (over 25 min). The predictive effect of the combination of TBA, DTA, and RENAL score was higher than the predictive effect of RENAL score alone for WIT (area under curve: 0.786 versus 0.72).

Conclusion

TBA and DTA are independently associated with the WIT of RPN, which provides additional assessment value for the complexity of kidney cancer in RPN over the RENAL score.

The Impact of Postoperative Renal Function Recovery after Laparoscopic and Robot-Assisted Partial Nephrectomy in Patients with Renal Cell Carcinoma

Background and objectives: This study aimed to evaluate the association between warm ischemic time (WIT) and postoperative renal function using Trifecta achievement in patients with renal cell carcinoma (RCC) who underwent robotic (RAPN) or laparoscopic partial nephrectomy (LPN). Materials and Methods: We conducted a retrospective multicenter cohort study of patients with RCC who underwent RAPN (RAPN group) or LPN (LPN group) at three institutions in Japan between March 2012 and October 2021. The primary endpoints were the rate of trifecta achievement in both surgical techniques and the association between WIT and recovery of postoperative renal function surgical outcomes. Results: The rate of trifecta achievement was significantly lower in patients with LPN than in those with RAPN (p < 0.001). WIT ≥ 25 min were 18 patients (18%) in the RAPN group and 89 (52.7%) in the LPN group. The postoperative estimated glomerular filtration rate (eGFR) was almost the same. However, 13 patients (7.7%) had a decreased in eGFR ≥ 15% at 3 months after LPN compared with the preoperative eGFR. Conclusions: The rate of trifecta achievement in the RAPN group was significantly higher than that in the LPN group. However, eGFR was identified as relatively better preserved after PN in both groups.

A Report of 61 Cases of Retroperitoneal Laparoscopic Nephron-Sparing Surgery and Factors Affecting Postoperative Renal Function

Objective

To explore the situation of 61 patients with renal tumors who underwent retroperitoneal laparoscopic nephron-sparing surgery (RLNSS) and the factors affecting postoperative renal function.

Methods

A total of 61 patients with renal tumors who underwent RLNSS in our hospital from January 2018 to January 2021 were included in this study. All patients were treated with RLNSS. The clinical data of patients were recorded. Before operation and 3 months after operation, the change value of glomerular filtration rate (ΔGFR) was measured by the Gates method. Multivariate linear regression was used to analyze the related factors affecting postoperative renal function.

Results

All 61 patients successfully completed the operation. The mean operative time was 60–150 min‚ average (98.75 ± 14.38) min. The estimated intraoperative blood loss was 20–310 ml‚ average (107.93 ± 68.55) ml. Intraoperative warm ischemia time (WIT) was 0–39 min, with an average of (21.16 ± 6.47) min. All patients' pathological margins were negative after operation. In all patients, there were 5 postoperative complications, including 2 cases of renal wound bleeding (3.28%), 1 case of hematuria (1.64%), 1 case of urinary fistula (1.64%), and 1 case of subcutaneous emphysema (1.64%). There were significant differences in tumor diameter, preoperative GFR, operation time and WIT (P < 0.05). Multivariate analysis showed that tumor diameter, preoperative GFR, and WIT were all factors affecting the postoperative renal function of patients with RLNSS (P < 0.05).

Conclusion

RLNSS has a good curative effect on patients with renal tumor, and tumor diameter, preoperative GFR, and WIT were all factors affecting the postoperative renal function of patients with RLNSS.

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.

Warm ischemia time length during on-clamp partial nephrectomy: dose it really matter?

BACKGROUND

The impact of warm ischemia time (WIT) on renal functional recovery remains controversial. We examined the length of WIT >30 min. on the long-term renal function following on-clamp partial nephrectomy (PN).

METHODS

Data from 23 centers for patients undergoing on-clamp PN between 2000 and 2018 were analyzed. We included patients with two kidneys, single tumor, cT1, minimum 1-year followup, and preoperative eGFR ≥60 ml/min/1.73m2. Patients were divided into two groups according to WIT length: group Ⅰ "WIT ≤30 min." and group Ⅱ "WIT >30 min.". A propensity-score matched analysis (1:1 match) was performed to eliminate potential confounding factors between groups. We compared eGFR values, eGFR (%) preservation, eGFR decline, events of chronic kidney disease (CKD) upgrading, and CKD-free progression rates between both groups. Cox regression analysis evaluated WIT impact on upgrading of CKD stages.

RESULTS

The primary cohort consisted of 3526 patients: group Ⅰ (n=2868) and group Ⅱ (n=658). After matching the final cohort consisted of 344 patients in each group. At last followup, there were no significant differences in median eGFR values at 1, 3, 5, and 10 years (P>0.05) between the matched groups. In addition, the median eGFR (%) preservation and absolute eGFR change were similar (89% in group Ⅰ vs. 87% in group Ⅱ, p=0.638) and (-10 in group Ⅰ vs. -11 in group Ⅱ, p=0.577), respectively. The 5 years new-onset CKD-free progression rates were comparable in the non-matched groups (79% in group Ⅰ vs. 81% in group Ⅱ, log-rank, p=0.763) and the matched groups (78.8% in group Ⅰ vs. 76.3% in group Ⅱ, log-rank, p=0.905). Univariable Cox regression analysis showed that WIT >30 min. was not a predictor of overall CKD upgrading (HR:0.953, 95%CI 0.829-1.094, p=0.764) nor upgrading into CKD stage ≥Ⅲ (HR:0.972, 95%CI 0.805-1.173, p=0.764). Retrospective design is a limitation of our study.

CONCLUSIONS

Our analysis based on a large multicenter international cohort study suggests that WIT length during PN has no effect on the long-term renal function outcomes in patients having two kidneys and preoperative eGFR ≥60 ml/min/1.73m2.

Single-Site Sutureless Partial Nephrectomy for Small Exophytic Renal Tumors

Partial nephrectomy (PN) is the standard procedure for most patients with localized renal cancer. Laparoscopy has become the preferred surgical approach to target this cancer, but the steep learning curve with laparoscopic PN (LPN) remains a concern. In LPN intracorporeal suturing, the operation time is further extended even under robot assistance, a step which prolongs warm ischemic time. Herein, we shared our experience to reduce the warm ischemia time, which allows surgeons to perform LPN more easily by using a combination of hemostatic agents to safely control parenchymal bleeding. Between 2015 and 2018, we enrolled 52 patients who underwent LPN in our hospital. Single-site sutureless LPN and traditional suture methods were performed in 33 and 19 patients, respectively. Preoperative, intra-operative, and postoperative variables were recorded. Renal function was evaluated by estimated glomerular filtration rate (eGFR) pre- and postoperatively. The average warm ischemia time (sutureless vs. suture group; 11.8 ± 3.9 vs. 21.2 ± 7.2 min, p < 0.001) and the operation time (167.9 ± 37.5 vs. 193.7 ± 42.5 min, p = 0.035) were significantly shorter in the sutureless group. In the sutureless group, only 2 patients suffered from massive urinary leakage (>200 mL/day) from the Jackson Pratt drainage tube, but the leakage spontaneously decreased within 7 days after surgery. eGFR and serum hemoglobin were not found to be significantly different pre- and postoperatively. All tumors were removed without a positive surgical margin. All patients were alive without recurrent tumors at mean postoperative follow-ups of 29.3 ± 12.2 months. Single-site sutureless LPN is a feasible surgical method for most patients with small exophytic renal cancer with excellent cosmetic results without affecting oncological results.

Development of a risk scoring system for predicting acute kidney injury after minimally invasive partial and radical nephrectomy: a retrospective study

BACKGROUND

Acute kidney injury after partial or radical nephrectomy remains an unsolved problem even when using minimally invasive techniques. We aimed to identify risk factors for acute kidney injury (AKI) after minimally invasive nephrectomy and to develop a clinical risk scoring system.

METHODS

Medical records of 1762 patients who underwent minimally invasive laparoscopic or robot-assisted laparoscopic partial (n = 1009) or radical (n = 753) nephrectomy from December 2005 to November 2018 were reviewed. Candidate risk factors were screened using univariate analysis and ranked using linear discriminant analysis; top ranking factors were incorporated into a multivariate logistic regression model. Then, the final clinical scoring system was created based on the estimated odds ratios.

RESULTS

The incidence of acute kidney injury after partial or radical nephrectomy was 20.3 and 61.6%, respectively. Risk factors incorporated into the scoring system included: size of the parenchymal mass removed (3 < parenchymal mass ≤ 4 cm, 1 point; 4 < parenchymal mass ≤ 6 cm, 3 points; parenchymal mass > 6 cm, 5 points), male sex (2 points), diabetes mellitus (1 point), warm ischemia time ≥ 25 min (1 point), and immediate postoperative neutrophil count ≥ 12,000 µl^-1 (1 point) in patients with partial nephrectomy, and sex (male, 10 points; female, 7 points) in patients with radical nephrectomy. For risk scores of 0-4, 5-6, 7, 8-9, and 10 points, the probabilities of acute kidney injury were approximately 10, 20, 40, 60, and 80%, respectively. The predictive accuracy of the scoring system was 0.827 (95% CI 0.789-0.865).

CONCLUSION

Our risk scoring system could help clinicians identify those at risk of acute kidney injury after minimally invasive partial or radical nephrectomy, thereby optimizing postoperative management.

Comparisons of the safety and effectiveness of robot-assisted versus laparoscopic partial nephrectomy for large angiomyolipomas: a propensity score-matched analysis

OBJECTIVE

To compare the safety and effectiveness of robot-assisted partial nephrectomy (RAPN) versus laparoscopic partial nephrectomy (LPN) for large angiomyolipomas (AMLs).

MATERIALS AND METHODS

We retrospectively evaluated 150 patients who were treated with either RAPN or LPN for large angiomyolipomas from 2014 to 2018. Propensity score matching was performed on age, gender, BMI, Charlson Comorbidity Index, tumour side and size, preoperative eGFR and RENAL score.

RESULTS

In total, 63 and 87 patients underwent RAPNs and LPNs, respectively. There were more large and complex AMLs in the RAPN cohort, with the median tumour maximal diameters and RENAL scores differing between the two groups (8 versus 7 cm and 9 versus 8, P = 0.01). After matching, the median warm ischemic time was significantly shorter in the RAPNs versus the LPNs (17 versus 22 min, P = 0.001). The rate of intraoperative complications in the RAPNs appeared lower than the LPNs (3.2% versus 8.1%). The median postoperative length of stay was significantly shorter in the RAPN cohort than the LPNs (P = 0.001). Twelve months after surgery, RAPNs received a 94.6% renal function prevention; while this was 90.8% in LPNs (P = 0.001). Subgroup analysis indicated that prior selective arterial embolization (SAE) was related to better renal function preservation in the RAPN cohort (P = 0.01). No recurrence occurred in either of the two cohorts.

CONCLUSIONS

RAPN is a safe and effective alternative to LPNs for large AMLs with a shorter warm ischemic time and higher renal preservation rate. Recurrence was equivalent in both RAPNs and LPNs.

Robotic-assisted partial nephrectomy: evolving techniques and expanding considerations

PURPOSE OF REVIEW

Robotic-assisted partial nephrectomy (RAPN) continues to gain popularity in the setting of nephron-sparing surgery for small renal masses. Although the recent introduction of technological advancements has allowed for expanded roles for RAPN, the optimal techniques and approaches to the procedure remain controversial.

RECENT FINDINGS

Of recent interest has been the role of warm ischemia time and its impact on postoperative renal function. Available studies suggest that although warm ischemia time remains an independent and modifiable risk factor for postoperative renal function, the role for 'zero ischemia' RAPN is still unclear. Recent studies on complex and/or larger tumors have demonstrated the feasibility of the procedure with comparable short-term outcomes to the open approach. Although these results should currently be considered experimental, they do shed light on the growing role for RAPN. Surgeon comfort and tumor location remain important factors when determining a retroperitoneal or transperitoneal approach. Available research demonstrates shorter operative times, length of stay and potentially lower costs to the retroperitoneal approach.

SUMMARY

Robotic-assisted partial nephrectomy remains an evolving procedure. Although recent literature suggests the feasibility of new and novel techniques, variable approaches and expanded indications, prospective, long-term follow-up data are needed before a consensus can be reached.

Comparison of 3-dimensional laparoscopy and conventional laparoscopy in the treatment of complex renal tumor with partial nephrectomy: A propensity score-matching analysis

To compare the efficacies of 3-dimensional laparoscopic partial nephrectomy and conventional laparoscopic partial nephrectomy for complex renal tumors. The complex renal tumors was defined as Preoperative Aspects and Dimensions Used for an anatomical (PADAU) ≥10, including some cT1b tumors.This was a retrospective analysis of patients with local complex renal tumors who presented to our hospital from January 2014 to January 2018. All patients were managed with laparoscopic partial nephrectomy (LPN) or 3-dimensional partial nephrectomy (3DLPN).There were 48 patients in the LPN group and 60 in the 3DLPN group. In the matched groups, demographic and tumor characteristics including Charlson Comorbidity Index, PADUA, based on the preoperative images, were similar. By contrast, 3DLPN achieved better results in terms of warm ischemia time (19 vs 27 minutes), operation time (105 vs 128 minutes), postoperative complications (14.9% vs 23.4%), and marginal width (0.6 cm vs 0.4 cm). We found statistically significant differences in terms of length of stay, estimated blood loss (EBL), positive surgical margin (PSM), and conversion to open or radical nephrectomy (RN). Median follow-up time was 17 and 18.5 months for the LPN and 3DLPN groups, respectively. The recovery of renal function (% change eGFR, 0 vs -8.7) was significantly different between the 3DLPN and LPN groups, whereas 12-month recurrence-free survival did not differ.Both 3-dimensional laparoscopic nephron-sparing nephrectomy and conventional laparoscopic partial nephrectomy are safe, effective, and acceptable approaches to treating complex renal tumors, while the former may facilitate tumor resection and renorrhaphy for challenging cases, offering a minimally invasive surgical option for patients who may otherwise require open surgery.

Effect of Diabetes Mellitus on Acute Kidney Injury after Minimally Invasive Partial Nephrectomy: A Case-Matched Retrospective Analysis

Postoperative acute kidney injury (AKI) is still a concern in partial nephrectomy (PN), even with the development of minimally invasive technique. We aimed to compare AKI incidence between patients with and without diabetes mellitus (DM) and to determine the predictive factors for postoperative AKI. This case-matched retrospective study included 884 patients with preoperative creatinine levels ≤1.4 mg/dL who underwent laparoscopic or robot-assisted laparoscopic PN between December 2005 and May 2018. Propensity score matching was employed to match patients with and without DM in a 1:3 ratio (101 and 303 patients, respectively). Of 884 patients, 20.4% had postoperative AKI. After propensity score matching, the incidence of postoperative AKI in DM and non-DM patients was 30.7% and 14.9%, respectively (P < 0.001). In multivariate analysis, male sex and warm ischemia time (WIT) >25 min were significantly associated with postoperative AKI in patients with and without DM. In patients with DM, hemoglobin A1c (HbA1c) >7% was a predictive factor for AKI, odds ratio (OR) = 4.59 (95% CI, 1.47⁻14.36). In conclusion, DM increased the risk of AKI after minimally invasive PN; male sex, longer WIT, and elevated HbA1c were independent risk factors for AKI in patients with DM.