Robot-assisted laparoscopic partial nephrectomy versus laparoscopic partial nephrectomy: A propensity score-matched comparative analysis of surgical outcomes and preserved renal parenchymal volume

Assessing the safety of minimally invasive partial nephrectomy in octogenarians

As life expectancy continues to rise, there is a growing cohort of octogenarians that can have oncologic benefit from a partial nephrectomy. This study aims to analyze a large national dataset to compare the safety and outcomes in octogenarians receiving a nephrectomy. The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was utilized. All subjects 80-89 years old who received a minimally invasive partial nephrectomy (CPT: 50543) or radical nephrectomy (CPT: 50545, 50546) from 2016 to 2020 were included. Baseline characteristics, comorbidities, and postoperative complications were compared. Chi-square analysis and student t-tests were used to analyze categorical and continuous variables, respectively. 1765 procedures were performed on octogenarians, of which 1299 (73.6%) received a radical nephrectomy and 466 (26.4%) received a partial nephrectomy. When comparing preoperative comorbidities, octogenarians undergoing partial nephrectomy had lower rates of dyspnea at exertion (7.3 vs. 10.6%, p = 0.04), COPD (2.8 vs. 5.9%, p = 0.01), and chronic steroid use (1.5 vs. 3.3%, p = 0.04). No statistically significant differences were seen in any minor (Clavien 1/2) or major post-operative complications (Clavien 3/4). Readmissions were higher in those who received a partial nephrectomy (10.5 vs. 6.5%, p = 0.01); however, there were no significant differences in reoperation (2.4 vs. 1.7%, p = 0.36) or mortality (1.3 vs. 1.8%, p = 0.48). Partial nephrectomy is a safe and feasible operation in octogenarians. Preoperative counseling and appropriate patient selection remain imperative.

Clinical outcomes of robotic-assisted laparoscopic partial nephrectomy with renal hypothermia perfusion by renal artery balloon catheter in treating patients with complex renal tumors

Objective

This study aimed to investigate the safety and efficacy of renal hypothermic perfusion by renal artery balloon catheter during robot-assisted laparoscopic partial nephrectomy (P-RALPN) for patients with complex renal tumors.

Materials and methods

We retrospectively identified 45 patients with complex renal tumors who received standard robot-assisted laparoscopic partial nephrectomy (S-RALPN) and 11 patients treated with P-RALPN from September 2017 to October 2021. Preoperative patients’ characteristics and intraoperative surgical parameters including operating time, blood loss, hospitalization, pre- and post-surgical glomerular filtration rate (GFR), and postoperative survival time were collected and compared between the two groups. The patients’ body temperature, real-time kidney temperature, and short-term renal function were analyzed in the P-RALPN group.

Results

There was no statistically significant difference on median intraoperative estimated blood loss and postoperative hospitalization between the two groups. Patients who received P-RALPN had a slightly longer operative time than those who received S-RALPN (103.1 versus 125.9; p = 0.09). In the P-RALPN group, the volume of perfusion solution was 533.2 ml (range, 255.0–750.0 ml), the median temperature of kidney was 22.6°C (range, 21.7–24.1°C) after the kidney cools down, and the median minimum intraoperative temperature of patients was 36.1°C (range 35.2–36.7°C). The ischemia time in the S-RALPN group was markedly lower than that in the P-RALPN group (21.5 versus 34.8; p < 0.01). However, the loss of GFR was much higher for the S-RALPN group after the surgery. (28.9 versus 18.4; p < 0.01). Importantly, patients had similar postoperative survival time between the two groups (p = 0.42; HR = 0.27).

Conclusion

P-RALPN is a safe and feasible surgery in the treatment of patients with complex renal tumors, which provides a new operative approach for clinicians to treat these patients.

Robot-assisted versus conventional laparoscopic partial nephrectomy for renal hilar tumors: Parenchymal preservation and functional recovery

OBJECTIVE

To determine whether robot-assisted laparoscopic partial nephrectomy (RALPN) can benefit patients in terms of functional recovery in the treatment of renal hilar tumors compared to conventional laparoscopic partial nephrectomy (CLPN).

METHODS

Between January 2019 and July 2021, patients with hilar tumors who underwent partial nephrectomy (PN) were acquired at our center and were classified into RALPN and CLPN groups. Ipsilateral parenchymal volume (IPV) and glomerular filtration rate (GFR) were determined independently 3-5 days before and 3 months after PN using contrast-enhanced computed tomography and nuclear renal scans. Pearson correlation was used to determine the link between ipsilateral GFR preservation and IPV preserved. Concurrently, multivariable analysis was employed to determine characteristics associated with functional recovery.

RESULTS

A total of 96 patients with hilar tumors were studied, of which 41 received RALPN and 55 received CLPN. Excisional parenchymal volume was 27 and 37 cm³ (p = 0.005) in RALPN and CLPN groups, respectively, and IPV preserved was 77% and 68% (p < 0.001). Furthermore, the ipsilateral GFR preserved was 77.7% and 75.3%, respectively (p = 0.003). On Pearson correlation, ipsilateral GFR preservation was linked with IPV preserved (r = 0.36, p < 0.001). According to a multivariate study, baseline GFR, IPV preserved, and surgical procedures (RALPN vs. CLPN) were significant factors influencing functional recovery.

CONCLUSION

Our study suggests that RALPN, rather than CLPN, can achieve better functional recovery in the treatment of hilar tumors due to its ability to win more IPV preserved. RALPN should be recommended as the first-line treatment for hilar tumors, but randomized controlled trials are required to validate our findings.

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.

Prediction of significant renal function decline after open, laparoscopic, and robotic partial nephrectomy: External validation of the Martini's nomogram on the RECORD2 project cohort

OBJECTIVES

Martini et al. developed a nomogram to predict significant (>25%) renal function loss after robot-assisted partial nephrectomy and identified four risk categories. We aimed to externally validate Martini's nomogram on a large, national, multi-institutional data set including open, laparoscopic, and robot-assisted partial nephrectomy.

METHODS

Data of 2584 patients treated with partial nephrectomy for renal masses at 26 urological Italian centers (RECORD2 project) were collected. Renal function was assessed at baseline, on third postoperative day, and then at 6, 12, 24, and 48 months postoperatively. Multivariable models accounting for variables included in the Martini's nomogram were applied to each approach predicting renal function loss at all the specific timeframes.

RESULTS

Multivariable models showed high area under the curve for robot-assisted partial nephrectomy at 6- and 12-month (87.3% and 83.6%) and for laparoscopic partial nephrectomy (83.2% and 75.4%), whereas area under the curves were lower in open partial nephrectomy (78.4% and 75.2%). The predictive ability of the model decreased in all the surgical approaches at 48 months from surgery. Each Martini risk group showed an increasing percentage of patients developing a significant renal function reduction in the open, laparoscopic and robot-assisted partial nephrectomy group, as well as an increased probability to develop a significant estimated glomerular filtration rate reduction in the considered time cutoffs, although the predictive ability of the classes was <70% at 48 months of follow-up.

CONCLUSIONS

Martini's nomogram is a valid tool for predicting the decline in renal function at 6 and 12 months after robot-assisted partial nephrectomy and laparoscopic partial nephrectomy, whereas it showed a lower performance at longer follow-up and in patients treated with open approach at all these time cutoffs.

Comparison of parenchymal volume loss assessed by three-dimensional computed tomography volumetry and renal functional recovery between conventional and robot-assisted laparoscopic partial nephrectomy

OBJECTIVES

We retrospectively investigated if robot-assisted laparoscopic partial nephrectomy (RAPN) contributes to a decrease in resected parenchymal volume (RPV), an increase in postoperative parenchymal volume (PPV), and an improvement of postoperative renal function when compared with conventional laparoscopic partial nephrectomy (LPN) using a three-dimensional image analysis system.

METHODS

Patients who underwent LPN (n = 37) and RAPN (n = 66) from November 2013 to November 2018 were included in this study. All patients had a tumor diameter of 4 cm or less. Patients with an anatomical or functional single kidney were excluded. RPV and PPV were measured using SYNAPSE VINCENT®. The surgical outcomes were compared between the two groups.

RESULTS

Warm ischemic time in the RAPN group was significantly shorter than that in the LPN group (p < 0.001). The ratio of RPV to tumor volume (RPV/TV) in the RAPN group was significantly lower than that in the LPN group (p = 0.016). PPV in the RAPN group was significantly higher than that in the LPN group (p = 0.049). The decreased estimated glomerular filtration rate in the RAPN group was significantly lower than that in the LPN group on days 1, 7, 30, 90, and 180 after surgery.

CONCLUSIONS

Postoperative renal function in the RAPN group was significantly better than that in the LPN group in both the short and long term. In addition to a short warm ischemia time, the decreased RPV/TV and increased PPV may have contributed to the improvement of postoperative 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.

Validation of predictive model for new baseline renal function after robot-assisted partial nephrectomy or radical nephrectomy in Japanese patients

PURPOSE

The study aim was to externally validate a new predictive model for new baseline glomerular filtration rate post-nephrectomy among Japanese patients.

MATERIALS AND METHODS

Patients with renal tumors who underwent radical nephrectomy or robot-assisted partial nephrectomy at a single Japanese institution in 2000-2020 were retrospectively analyzed. New baseline glomerular filtration rate is defined as the final estimated glomerular filtration rate within postoperative 3-12 months. The correlation/bias/accuracy/precision of the equation was examined by comparing the calculated new baseline glomerular filtration rate with the observed rate.

RESULTS

The study included 485 cases of radical nephrectomy, and 1030 cases of robot-assisted partial nephrectomy. The correlation/bias/accuracy/precision of the new equation predicting new baseline glomerular filtration rate were 0.86/-0.92/95.9/-5.65-3.62 in robot-assisted partial nephrectomy and 0.79/-1.02/87.8/-6.26-3.91 in radical nephrectomy, respectively. The fractional polynomial regression line approximated zero and its pointwise 95% confidence interval was considerably tight for the majority of both cohorts. The 95% confidence interval to discriminate new baseline glomerular filtration rates of ≥45 ml/min/1.73 m2 from receiver operating curves was 0.96 (0.95-0.97) and 0.89 (0.87-0.92) in robot-assisted partial nephrectomy and radical nephrectomy, respectively. Various preoperative factors including age, tumor size, complexity, body mass index, hypertension, and diabetes did not affect the predictive ability (correlation > 0.7) from the subgroup analysis.

CONCLUSION

The novel simple equation can accurately predict new baseline glomerular filtration rates after radical and robot-assisted partial nephrectomies in Japanese patients. This model will help physicians choose surgical treatments for renal tumors in daily clinical practice.

Renal Functional and Perioperative Outcomes of Retroperitoneal Robot-Assisted Versus Laparoscopic Partial Nephrectomy with Segmental Renal Artery Clamping

Background: Retroperitoneal approach and segmental renal artery clamping in partial nephrectomy are techniques that facilitate postoperative recovery and renal function preservation. This study aimed to compare the renal function preservation and perioperative outcomes of robot-assisted partial nephrectomy (RAPN) and laparoscopic partial nephrectomy (LPN) with these techniques. Materials and Methods: Clinical parameters of 43 patients who had undergone retroperitoneal RAPN from March 2017 to December 2019 were retrospectively collected and compared with those of 52 patients who had undergone retroperitoneal LPN at the same period in our institution. Differences in operating time, warm ischemia time, estimated blood loss, complications, postoperative hospital stay, as well as renal function loss were compared between the two groups. Results: Background characteristics between RAPN and LPN groups such as age, gender, BMI, and tumor characteristics were comparable. All RAPNs and LPNs were successfully completed without conversion to open surgery or nephrectomy. No significant difference in operating time, estimated blood loss, complications, and postoperative hospital stay was observed between RAPN and LPN groups. The warm ischemia time in RAPN group was slightly shorter than that of LPN groups (P = .054). Compared with the LPN group, the RAPN group was significantly associated with less glomerular filtration rate reduction and renal volume loss rate (P = .042 and P = .013, respectively). Conclusions: The perioperative outcomes were comparable between the two groups. However, compared with LPN, RAPN had superiority in preserving renal function in our series.

Optimal Surgical Outcome of Minimally Invasive Partial Nephrectomy (MIPN) Based on an Early Postoperative Estimated Glomerular Filtration Rate (eGFR)

PURPOSE OF REVIEW

To compare laparoscopic partial nephrectomy (LPN) and robot-assisted partial nephrectomy (RAPN) performed in two European tertiary centers using the classic optimal surgical definition - "MIC" - and a new optimal surgical definition: the "Novel TRIFECTA" (NT) concept. We sought to strengthen the PN evidence and to test the NT's performance.

RECENT FINDINGS

The study population comprehended 505 cases of localized kidney cancer from two tertiary centers between 2012 and 2019. The NT achievement was higher in the RAPN group when compared to LPN (70.5 vs. 87.4%; p = 0.004), while no differences were found when considering the MIC criteria. Also, a similar high-grade complications rate (Clavien-Dindo > III) and operative time (105 min vs. 100 min; p = NS) were found. In the multivariable regression, the RAPN approach was a predictor of NT achievement (OR 2.45; p = 0.008). NT achievement was higher in the RAPN group, while similar results were found when evaluating the MIC criteria. The NT definition could be more sensitive to the individual-specific responses related to the PN.

Robot-Assisted Laparoscopic Partial Nephrectomy for Allograft Renal Cell Carcinoma: A Case Report

BACKGROUND

Nephron-sparing surgery is required for patients with kidney transplant with organ-confined renal cell carcinoma (RCC) in the allograft kidney to preserve renal function. Robot-assisted laparoscopic partial nephrectomy (RAPN) is expected to be the optimal surgical approach for these patients, as in the general population. However, RAPN for RCC arising in the allograft kidney is rarely reported. Here, we report 2 cases of patients who underwent RAPN for allograft RCC.

CASE PRESENTATION

Two patients were diagnosed with RCC in the renal allograft based on enhanced computed tomography findings. Case 1 was a 69-year-old man with a 32-mm mass in the middle portion of the right iliac fossa renal allograft, and case 2 was a 55-year-old man with a 24-mm mass in the lower pole of the right iliac fossa renal allograft. In each patient, RAPN was performed for the renal mass through a transperitoneal approach, with clamping of the renal artery. No major perioperative complications occurred in either patient, negative surgical margins were achieved, and no significant changes in kidney function were observed during either surgery. Pathologic findings showed clear cell RCC in case 1 and papillary RCC in case 2.

CONCLUSION

RAPN can be a feasible and effective treatment option for allograft RCC.

Clinical advantages of robot-assisted partial nephrectomy versus laparoscopic partial nephrectomy in terms of global and split renal functions: A propensity score-matched comparative analysis

OBJECTIVES

To identify predictors of renal function preservation, and to compare the global and split renal function outcomes of robot-assisted partial nephrectomy and laparoscopic partial nephrectomy.

METHODS

Demographic, operative and pathological data, as well as renal function outcomes, of 251 patients who underwent laparoscopic (n = 104) and robot-assisted (n = 147) partial nephrectomy between 2008 and 2018 were retrospectively analyzed. Propensity score matching (1:1) was carried out to adjust for potential baseline confounders. Functional outcomes were assessed based on the estimated glomerular filtration rate and dynamic renal scintigraphy (using ^99m Tc-mercaptoacetyltriglycine), including renal volumetric analysis.

RESULTS

A total of 98 patients were allocated to each partial nephrectomy group. Ischemic (laparoscopic vs robot-assisted partial nephrectomy: 29 vs 15 min, P < 0.001) and operative times (181 vs 100 min, P < 0.001) were shorter in robot-assisted partial nephrectomy. The preservation ratio of global renal function at 3 months (88.3% vs 91.4%, P = 0.040) and 12 months (87.8% vs 91.5%, P = 0.010) postoperatively, and the renal function of the operated kidney (80.3% vs 88.2%, P < 0.001) were greater after robot-assisted partial nephrectomy. In robot-assisted partial nephrectomy, the volume of resected parenchyma was significantly smaller (27.2 vs 15.5 mL, P < 0.001), resulting in greater postoperative normal parenchymal volumes (120 vs 132 mL, P < 0.001) and a greater parenchymal preservation ratio (81.1% vs 90.1%, P < 0.001). The parenchymal preservation ratio was the strongest predictor of renal function preservation after surgery (P < 0.001, odds ratio 6.02).

CONCLUSIONS

Robot-assisted partial nephrectomy allows better preservation of split renal function than laparoscopic partial nephrectomy by increasing the parenchymal preservation ratio. This translates into better postoperative global renal function.

First cases of combined full robotic partial nephrectomy and colorectal resections: Results and new perspectives

Background

Nowadays the robotic platform is widespread in general surgery, urology, and gynecology. Combined surgery may represent an alternative to sequential procedures and it allows the treatment, at the same time, of coexisting lesions; in this perspective, full‐robotic multiorgan surgery is starting to gain interest from surgeons worldwide.

Methods

Between April and June 2019, two patients presenting with synchronous colorectal and kidney cancers underwent, respectively, full‐robotic right colectomy with right partial nephrectomy and anterior rectal resection with left partial nephrectomy. Surgeries were performed by both the general surgery and urology team.

Results

No intraoperative complications were registered and the postoperative course was uneventful in both cases.

Conclusions

Combined multiple organ surgery with full robotic technique is safe and offers oncological adequate results. A multi‐team surgical pre‐planning is mandatory to reduce invasiveness and operative time. To the best of our knowledge, these are the first reports of full robotic partial nephrectomy combined with colorectal procedures.

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.

Robot-assisted versus laparoscopic partial nephrectomy for anatomically complex T1b renal tumors with a RENAL nephrometry score ≥7: A propensity score-based analysis

Objectives

To present the perioperative, functional, and oncological outcomes of robot‐assisted partial nephrectomy (RPN) compared with laparoscopic partial nephrectomy (LPN) for anatomically complex T1b renal tumors with RENAL nephrometry scores ≥7.

Patients and methods

One hundred and seventy patients, during the study period, were retrospectively reviewed in our analysis according to inclusion criteria. Propensity score matching (PSM) (1:1) method was applied to impose restrictions on the potential baseline confounders. The comparisons of perioperative and functional outcomes between the RPN and LPN groups were conducted and analyzed after PSM, Kaplan‐Meier analyses were performed to assess the differences about oncological outcomes between the two groups before and after PSM.

Results

One hundred and nine and 61 T1b renal tumors with RENAL scores ≥7 were identified in the LPN and RPN groups, respectively. All significant differences in baseline characteristics disappeared after PSM. Except for 3 patients missing an appropriate pair, all the patients in the RPN group were successfully matched to 58 patients in the LPN group in a 1:1 ratio. Within the matched cohort, the RPN group was related to a significantly shorter mean operating time (OT) (P = .040), shorter mean warm ischemia time (WIT) (P = .023), and shorter median postoperative hospital stay (P = .023). The possibilities of surgical conversion, postoperative complication, and positive surgical margin were similar in the LPN and RPN groups. And there was also no significant difference in the pathological, renal functional, and oncological outcomes between the two series.

Conclusions

For patients with anatomically complex T1b renal tumors with a RENAL nephrometry score ≥7, RPN had an advantage over LPN in reducing OT, WIT, and postoperative hospital stay length without increasing the risk of complications and weakening the oncological control, while the two surgical methods were similar in renal functional preservation.

The 3-D Volumetric Measurement Including Resected Specimen for Predicting Renal Function AfterRobot-assisted Partial Nephrectomy

OBJECTIVE

To investigate the relationship between postoperative renal function and resected cortex margin volume calculated by a 3-dimensional reconstruction technique based on the resected specimen, and to determine predictors of renal function after robot-assisted partial nephrectomy.

METHODS

A total of 114 patients underwent robot-assisted partial nephrectomy from 2014 to 2018. Patients without a 1 mm slice computed tomography or renal scintigraphy were excluded. We identified the margins of the tumor from each resected specimen with 2 mm margin being added as the ischemic margin. The volume of the renal cortex was calculated automatically using 3-dimensional volume analyzer software. The total margin volume was excluded from the ipsilateral cortex volume to calculate the cortex volume split. Predicted estimated glomerular filtration rate (eGFR) was calculated using the change in cortex volume and then compared with the actual eGFR.

RESULTS

Eighty-two patients were included in this retrospective study. Sixty-six patients (80%) were cT1a. A strong correlation was observed between renal scintigraphy split and pre- and postoperative cortex volume split (Pearson correlation coefficient r = 0.9330 and 0.8742, respectively). The predicted eGFR correlated strongly with post 1, 3, 6, and 12 months eGFR (r = 0.8929, 0.9294, 0.9320, and 0.8952, respectively). Preoperative relative renal function and total cortex margin volume were independent risk factors for decreasing postoperative renal function.

CONCLUSION

This precise volumetric assessment that includes the resected margin is an alternative to renal scintigraphy for predicting postoperative relative renal function. The healthy cortex margin volume calculated by the reconstruction technique is an independent risk factor of decreasing postoperative renal function.