Ipsilateral Glomerular Filtration Rate Research Articles

Dose-Effect Relationship of Kidney Function After SABR for Primary Renal Cell Carcinoma: TROG 15.03 FASTRACK II

BackgroundStereotactic ablative body radiotherapy (SABR) is a novel option to treat primary renal cell carcinoma (RCC). However, a high radiation dose may be received by the treated kidney, which may affect its function post-treatment. This study investigates the dose-effect relationship of kidney SABR with posttreatment renal function. MethodsThis was a prespecified secondary endpoint of the multicenter FASTRACK II clinical trial (NCT02613819). Patients received either 26 Gy in a single fraction (SF) for tumors with a maximal diameter of 4 cm or less, or 42 Gy in three fractions (multi-fraction (MF)) for larger tumors. To determine renal function change, 99mTc-DMSA SPECT/CT scans were acquired, and the glomerular filtration rate (GFR) was estimated at baseline, 12-, and 24-months post-treatment. Imaging datasets were rigidly registered to the planning CT where kidneys were segmented to calculate dose-response curves. ResultsFrom 71 enrolled patients, data from 36 (51%) and 26 (37%) patients were included in this study based on availability of post-treatment data at 12- and 24-months, respectively. The ipsilateral kidney GFR decreased from baseline by 42% and 39% in the SF cohort, and by 45% and 62% in the MF cohort, at 12- and 24-months respectively (p-values < 0.03). The loss in renal function was 3.6±0.8% and 4.5±1.0% in the SF cohort, and 1.7±0.1% and 1.7±0.2% in the MF cohort, at 12- and 24-months respectively. The major loss in renal function occurred in high-dose regions, where dose-response curves converged to a plateau. ConclusionsFor the first time in a multicenter study, the dose-effect relationship at 12- and 24-months post-SABR treatment for primary RCC was quantified. Kidney function reduces linearly with dose up to 100 Gy BED3.

Parenchymal volume preservation during partial nephrectomy: improved methodology to assess impact and predictive factors.

To rigorously evaluate the impact of the percentage of parenchymal volume preserved (PPVP) and how well the preserved parenchyma recovers from ischaemia (Recischaemia) on functional outcomes after partial nephrectomy (PN) using an accurate and objective software-based methodology for estimating parenchymal volumes and split renal function (SRF). A secondary objective was to assess potential predictors of the PPVP. A total of 894 PN patients with available studies (2011-2014) were evaluated. The PPVP was measured from cross-sectional imaging at ≤3 months before and 3-12 months after PN using semi-automated software. Pearson correlation evaluated relationships between continuous variables. Multivariable linear regression evaluated predictors of ipsilateral glomerular filtration rate (GFR) preserved and the PPVP. Relative-importance analysis was used to evaluate the impact of the PPVP on ipsilateral GFR preserved. Recischaemia was defined as the percentage of ipsilateral GFR preserved normalised by the PPVP. The median tumour size and R.E.N.A.L. nephrometry score were 3.4 cm and 7, respectively. In all, 49 patients (5.5%) had a solitary kidney. In all, 538 (60%)/251 (28%)/104 (12%) patients were managed with warm/cold/zero ischaemia, respectively. The median pre/post ipsilateral GFRs were 40/31 mL/min/1.73 m2, and the median (interquartile range [IQR]) percentage of ipsilateral GFR preserved was 80% (71-88%). The median pre/post ipsilateral parenchymal volumes were 181/149 mL, and the median (IQR) PPVP was 84% (76-92%). In all, 330 patients (37%) had a PPVP of <80%, while only 34 (4%) had a Recischaemia of <80%. The percentage of ipsilateral GFR preserved correlated strongly with the PPVP (r = 0.83, P < 0.01) and loss of parenchymal volume accounted for 80% of the loss of ipsilateral GFR. Multivariable analysis confirmed that the PPVP was the strongest predictor of ipsilateral GFR preserved. Greater tumour size and endophytic and nearness properties of the R.E.N.A.L. nephrometry score were associated with a reduced PPVP (all P ≤ 0.01). Solitary kidney and cold ischaemia were associated with an increased PPVP (all P < 0.05). A reduced PPVP predominates regarding functional decline after PN, although a low Recischaemia can also contribute. Tumour-related factors strongly influence the PPVP, while surgical efforts can improve the PPVP as observed for patients with solitary kidneys.

Functional recovery after partial nephrectomy: next generation analysis.

To provide a more rigorous assessment of factors affecting functional recovery after partial nephrectomy (PN) using novel tools that allow for analysis of more patients and improved accuracy for assessment of parenchymal volume loss, thereby revealing the potential impact of secondary factors such as ischaemia. Of 1140 patients managed with PN (2012-2014), 670 (59%) had imaging and serum creatinine levels measured before and after PN necessary for inclusion. Recovery from ischaemia was defined as the ipsilateral glomerular filtration rate (GFR) saved normalised by parenchymal volume saved. Acute kidney injury was assessed through Spectrum Score, which quantifies the degree of acute ipsilateral renal dysfunction due to exposure to ischaemia that would otherwise be masked by the contralateral kidney. Multivariable regression was used to identify predictors of Spectrum Score and Recovery from Ischaemia. In all, 409/189/72 patients had warm/cold/zero ischaemia, respectively, with median (interquartile range [IQR]) ischaemia times for cold and warm ischaemia of 30 (25-42) and 22 (18-28) min, respectively. The median (IQR) global preoperative GFR and new baseline GFR (NBGFR) were 78 (63-92) and 69 (54-81) mL/min/1.73 m2 , respectively. The median (IQR) ipsilateral preoperative GFR and NBGFR were 40 (33-47) and 31 (24-38) mL/min/1.73 m2 , respectively. Functional recovery correlated strongly with parenchymal volume preserved (r = 0.83, P < 0.01). The median (IQR) decline in ipsilateral GFR associated with PN was 7.8 (4.5-12) mL/min/1.73 m2 with loss of parenchyma accounting for 81% of this loss. The median (IQR) recovery from ischaemia was similar across the cold/warm/zero ischaemia groups at 96% (90%-102%), 95% (89%-101%), and 97% (91%-102%), respectively. Independent predictors of Spectrum Score were ischaemia time, tumour complexity, and preoperative global GFR. Independent predictors of recovery from ischaemia were insulin-dependent diabetes mellitus, refractory hypertension, warm ischaemia, and Spectrum Score. The main determinant of functional recovery after PN is parenchymal volume preservation. A more robust and rigorous evaluation allowed us to identify secondary factors including comorbidities, increased tumour complexity, and ischaemia-related factors that are also independently associated with impaired recovery, although altogether these were much less impactful.

PD08-06 FULLY AUTOMATED TUMOR CONTACT SURFACE AREA PREDICTS POSTOPERATIVE IPSILATERAL GFR PRESERVATION FOLLOWING PARTIAL NEPHRECTOMY

You have accessJournal of UrologyCME1 Apr 2023PD08-06 FULLY AUTOMATED TUMOR CONTACT SURFACE AREA PREDICTS POSTOPERATIVE IPSILATERAL GFR PRESERVATION FOLLOWING PARTIAL NEPHRECTOMY Andrew Wood, Nicholas Heller, Tarik Benidir, Nour Abdallah, Fabian Isensee, Resha Tejpaul, Chalairat Suk-Ouichai, Caleb Curry, Alex You, Erick Remer, Samuel Haywood, Robert Abouassaly, Steven Campbell, Nikolaos Papanikolopoulos, and Christopher Weight Andrew WoodAndrew Wood More articles by this author , Nicholas HellerNicholas Heller More articles by this author , Tarik BenidirTarik Benidir More articles by this author , Nour AbdallahNour Abdallah More articles by this author , Fabian IsenseeFabian Isensee More articles by this author , Resha TejpaulResha Tejpaul More articles by this author , Chalairat Suk-OuichaiChalairat Suk-Ouichai More articles by this author , Caleb CurryCaleb Curry More articles by this author , Alex YouAlex You More articles by this author , Erick RemerErick Remer More articles by this author , Samuel HaywoodSamuel Haywood More articles by this author , Robert AbouassalyRobert Abouassaly More articles by this author , Steven CampbellSteven Campbell More articles by this author , Nikolaos PapanikolopoulosNikolaos Papanikolopoulos More articles by this author , and Christopher WeightChristopher Weight More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003239.06AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Tumor Contact Surface Area (CSA) is an externally validated nephrometry scoring system that requires measurement of multiple dimensions of cross sectional imaging. Despite studies demonstrating its ability to predict glomerular filtration rate (GFR) following partial nephrectomy (PN), its implementation has been slowed by required time investment and interobserver variability. We sought to evaluate the utility of artificial intelligence (AI) generated CSA as compared to human-generated CSA in predicting post-PN GFR. METHODS: A total of 300 patients with preoperative computerized tomography with early arterial contrast phase were identified from a cohort of 544 consecutive patients undergoing surgical extirpation for suspected renal cancer. A deep neural network approach was used to automatically segment kidneys and tumors, and then programed to generate the measurements and calculate tumor CSA. Human CSA scores were independently calculated by medical personnel blinded to AI-scores. Ipsilateral GFR before and after surgery was calculated from volumetric analyses of kidney parenchyma and pre and post-operative GFR values. AI-CSA and Human-CSA were then compared with regards to their ability to predict Ipsilateral GFR preservation. RESULTS: After removal of patients undergoing RN and those without requisite data for GFR calculation, a total of 150 patients were included in the analysis. There was significant agreement between Human CSA and AI-CSA on linear regression analysis (R2=0.74, p<0.0001). On univariate linear regression analysis, both AI- (r=0.217, p=0.0076) and Human generated (r=0.187, p=0.021) CSA similarly predicted ipsilateral GFR preservation. However, when incorporated into a MV model incorporating age, gender, body mass index, diabetes status, and ischemia time, only AI generated tumor CSA remained a significant predictor of ipsilateral GFR preservation (p=0.021). CONCLUSIONS: Fully automated tumor CSA calculations are not inferior, and may be superior, to human generated CSA calculations in predicting post-operative GFR after PN. Once validated, our results suggest that AI generated CSA could be delivered automatically from a preoperative CT scan to a clinician and patient at the point of care to aid in decision making. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e234 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Andrew Wood More articles by this author Nicholas Heller More articles by this author Tarik Benidir More articles by this author Nour Abdallah More articles by this author Fabian Isensee More articles by this author Resha Tejpaul More articles by this author Chalairat Suk-Ouichai More articles by this author Caleb Curry More articles by this author Alex You More articles by this author Erick Remer More articles by this author Samuel Haywood More articles by this author Robert Abouassaly More articles by this author Steven Campbell More articles by this author Nikolaos Papanikolopoulos More articles by this author Christopher Weight More articles by this author Expand All Advertisement PDF downloadLoading ...

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

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). 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. 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. 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.

Angiotensin II and the Renal Hemodynamic Response to an Isolated Increased Renal Venous Pressure in Rats.

Elevated central venous pressure increases renal venous pressure (RVP) which can affect kidney function. We previously demonstrated that increased RVP reduces renal blood flow (RBF), glomerular filtration rate (GFR), and renal vascular conductance (RVC). We now investigate whether the RAS and RBF autoregulation are involved in the renal hemodynamic response to increased RVP. Angiotensin II (ANG II) levels were clamped by infusion of ANG II after administration of an angiotensin-converting enzyme (ACE) inhibitor in male Lewis rats. This did not prevent the decrease in ipsilateral RBF (−1.9±0.4ml/min, p<0.05) and GFR (−0.77±0.18ml/min, p<0.05) upon increased RVP; however, it prevented the reduction in RVC entirely. Systemically, the RVP-induced decline in mean arterial pressure (MAP) was more pronounced in ANG II clamped animals vs. controls (−22.4±4.1 vs. −9.9±2.3mmHg, p<0.05), whereas the decrease in heart rate (HR) was less (−5±6bpm vs. −23±4bpm, p<0.05). In animals given vasopressin to maintain a comparable MAP after ACE inhibition (ACEi), increased RVP did not impact MAP and HR. RVC also did not change (0.018±0.008ml/minˑmmHg), and the reduction of GFR was no longer significant (−0.54±0.15ml/min). Furthermore, RBF autoregulation remained intact and was reset to a lower level when RVP was increased. In conclusion, RVP-induced renal vasoconstriction is attenuated when ANG II is clamped or inhibited. The systemic effect of increased RVP, a decrease in HR related to a mild decrease in blood pressure, is attenuated also during ANG II clamp. Last, RBF autoregulation remains intact when RVP is elevated and is reduced to lower levels of RBF. This suggests that in venous congestion, the intact RBF autoregulation could be partially responsible for the vasoconstriction.

Differential contribution of the factors determining long-term renal function after partial nephrectomy over time

PurposeTo define how much of renal function was determined by the preserved renal parenchymal volume and the ischemic insult during partial nephrectomy (PN) long after surgery. MethodsWe analyzed the data of 530 consecutive patients who had undergone PN. For all patients, renal function was measured preoperatively and again at 3 postoperative months, then annually using 99mTc-diethylenetriaminepentaacetic acid renal scan. Perioperative variables potentially affecting the long-term ipsilateral glomerular filtration rate (GFR) and their time-varying contribution were assessed using a linear mixed model. ResultsThe mean preoperative ipsilateral GFR was 42.9 ml/min, which decreased by 27.3% at 3 months but began to recover thereafter continuing until 4 years (Δ% GFR at 1, 2, 3, 4, and 5 years: 22.3%, 18.5%, 14.7%, 10.0%, and 9.6%, respectively). Parenchymal volume reduction and ischemic time were significantly associated with postoperative ipsilateral GFR throughout observation period unvarying with time. Diabetes and proteinuria were not significant determinants of ipsilateral function at 3 months but became significant at 5 years. In multivariate analysis regarding recovery slope, volume reduction (β = −0.026, SE 0.006, P < 0.0001), preoperative ipsilateral GFR (β = −0.021, SE 0.007, P = 0.0012), proteinuria (β = −0.942, SE 0.372, P = 0.0116), and diabetes (β = −0.396, SE 0.197, P = 0.0447) were independently significant. ConclusionIpsilateral renal function continued to improve until 5 years after PN. Parenchymal volume loss was the major determinant and its impact on long-term ipsilateral renal function remained constant while ischemic time affected early GFR reduction with its impact diminishing over time. Patient-related factors including diabetes and proteinuria gained significance over time and became independent determinants of recovery slope.

Surgical details and renal function change after robot-assisted partial nephrectomy.

To investigate whether differences in surgical details during robot-assisted partial nephrectomy impact postoperative renal function. Patient, tumor and perioperative characteristics of 751 patients who underwent robot-assisted partial nephrectomy were analyzed with respect to the difference in ipsilateral glomerular filtration rate measured by diethylenetetramine pentaacetic acid renal scan. Detailed surgical methods defined for tumor excision (cutting vs splitting), hemostasis (suturing vs clipping) and renorrhaphy (continuous vs interrupted) were analyzed for early glomerular filtration rate decline and long-term recovery. The glomerular filtration rate of the entire cohort decreased by 9.8mL/min/1.73m2 (22%) at 3months postoperatively, gradually increasing thereafter. The recovery slope was 1.7mL/min/1.73m2 /year during a median follow-up period of 23.0months. Early glomerular filtration rate decline was more pronounced in the cutting group (23.5 vs 20.1%, P=0.009). Clipping was associated with less glomerular filtration rate decline throughout the observation period, and the recovery slope was also significantly higher (2.7 vs 1.1mL/min/1.73m2 /year). In multivariate analysis, early decline was associated with age, preoperative glomerular filtration rate, parenchymal volume loss and ischemia >25min. With respect to long-term recovery, suturing had the greatest adverse impact (β=-5.060, P<0.0001, 95% confidence interval -7.709, -2.411) in addition to parenchymal volume reduction and early decline. In the propensity-matched cohort accounting for differences in tumor size and complexity, suturing was persistently associated with a significant glomerular filtration rate decline until >2years after surgery. Hemostatic sutures during robot-assisted partial nephrectomy might interfere with long-term renal function recovery irrespective of parameters that determine the initial function change. As the splitting method reduces the use of sutures, modifying these details might help preserve renal function.

The role of three-dimensional reconstruction in laparoscopic partial nephrectomy for complex renal tumors

BackgroundTo evaluate the role of three-dimensional (3D) reconstruction technique in renal function protection and ipsilateral parenchymal mass preserved after laparoscopic partial nephrectomy (LPN) in patients with complex renal tumor (R.E.N.A.L.score ≥ 8).MethodsA retrospective study enrolling 49 patients who suffered from RCC and underwent LPN at our center, from October 1, 2017, to October 31, 2018. Twenty-one patients (group A) underwent LPN with the 3D reconstruction technique before surgery, and the other 28 patients (group B) not. Preoperative and postoperative ipsilateral parenchymal mass volume and ipsilateral glomerular filtration rate (GFR) were analyzed 3–5 days prior and 3 months after PN. In order to compare the two groups, Mann-Whitney U test and chi-square tests were performed. The main limitation of this technique is that the volume calculations are partly performed manually.ResultsAll patients’ median renal score was 10 with no difference between the two groups (P = 0.89), and the median tumor size of the two groups was 3.2 cm (group A) and 3.3 cm (group B) respectively (P = 0.14). In addition, the median warm ischemia time of the two groups was 21 min (group A) and 26 min (group B) (P = 0.003). In group A and group B, the rate of preserved global GFR was 88% and 86% (P = 0.06), preserved ipsilateral GFR was 80% and 77% (P = 0.01), and preserved ipsilateral parenchymal was 84% and 80% (P = 0.03) separately.Conclusion3D reconstruction technique was a beneficial method for more renal function and more preserved renal parenchymal mass volume after LPN.Trial registrationYantai Yuhuangding Hospital, YHD[2017]212. Registered 1 January 2017 (prospectively registered), http://www.ytyhdyy.com/nav/103.htm.

Robot-assisted partial nephrectomy is associated with early recovery of renal function: Comparison of open, laparoscopic, and robot-assisted partial nephrectomy using DTPA renal scintigraphy.

To compare the functional outcomes of open, laparoscopic, and robot-assisted partial nephrectomy (OPN, LPN, and RAPN, respectively) using diethylene triamine penta-acetic acid (DTPA). We identified 610 patients who underwent partial nephrectomy for renal cell carcinoma (285 open partial nephrectomy [OPN], 96 laparoscopic partial nephrectomy [LPN], and 229 robot-assisted partial nephrectomy [RAPN]) with preoperative and postoperative DTPA within 1 year. We excluded multiple renal masses and history of immunotherapy or chemotherapy. Predictive factors for glomerular filtration rate (GFR) reduction were assessed using multivariate linear regression. Postoperative complications and disease-free survival were similar in the three groups. Within 1 postoperative year, OPN showed a significantly lower mean ipsilateral GFR than LPN and RAPN (28.9 versus 32.4 versus 32.7 mL/min/1.73 m 2 , respectively; P < 0.001). RAPN was associated with a significantly higher total GFR than OPN within 1 year (76.6 versus 71.2 mL/min/1.73 m 2 , respectively; P = 0.001). On multivariate analysis within 1 year, operation type (OPN versus RAPN: β = 2.82; 95% confidence interval, 1.17-4.48; P = 0.001) was significantly associated with GFR reduction. There was no difference in postoperative complications and disease-free survival among operation types. RAPN could help to promote earlier recovery of ipsilateral GFR than OPN.

Vascularized Parenchymal Mass Preserved with Partial Nephrectomy: Functional Impact and Predictive Factors

BackgroundPercentage parenchymal mass preserved (PPMP) is a key determinant of functional outcomes after partial nephrectomy (PN); however, predictors of PPMP have not been defined. ObjectiveTo provide a comprehensive analysis of the functional impact of and potential predictive factors for PPMP. Design, setting, and participantsWe analyzed data for 464 patients managed with PN at our center with necessary studies to determine vascularized parenchymal mass and function preserved within the operated kidney. PPMP was measured from computed tomography scans <2 mo before and 3–12 mo after PN. InterventionPN. Outcome measurements/statistical analysisRecovery from ischemia was defined as percentage ipsilateral glomerular filtration rate (GFR) preserved normalized by PPMP. We used Pearson correlation to evaluate the relationships between GFR preserved and PPMP. Multivariable logistic regression was used to assess predictors of PPMP. Result and limitationsNinety-six patients (21%) had a solitary kidney. The median tumor size and RENAL score were 3.5cm and 8, respectively. Cold/warm ischemia were utilized in 183/281 patients for which the median ischemia time were 28/20min. The median preoperative and postoperative vascularized parenchymal mass in the operated kidney were 194 and 157cm3, respectively, resulting in median PPMP of 84%. GFR preservation correlated strongly with PPMP (r=0.64; p<0.001). Recovery from ischemia was suboptimal (<80%) in 71 patients (15%), while suboptimal PPMP (<80%) was a more common adverse event, occurring in 160 patients (34%; p<0.001). Multivariable analysis demonstrated that greater tumor size and complexity were associated with lower PPMP (p≤0.04), while solitary kidney and hypothermia were associated with higher PPMP (p<0.001). Longer ischemia time was also associated with lower PPMP (p=0.003), probably reflecting the complexity of the surgery. Limitations include the retrospective design. ConclusionPPMP correlates strongly with functional outcomes after PN, and lower PPMP is the most common and important source of functional decline after PN. Larger tumors, greater tumor complexity, and prolonged ischemia time were associated with lower PPMP, while PPMP tended to be greater for solitary kidneys, confirming that PPMP is a modifiable factor. Patient summaryKidney function after partial nephrectomy primarily depends on the amount of vascularized kidney preserved by the procedure. Lower recovery of function is seen when operating on larger tumors in unfavorable locations, but preservation of the parenchymal mass can be improved when truly necessary, such as when operating on a tumor in a solitary kidney.

Evaluation of Quantitative and Qualitative Renal Outcome Following Nephron Sparing Surgery.

Purpose:Preservation of renal function after nephron-sparing surgery (NSS) is multifactorial and the impact of individual factors on it is still a debate. This prospective study investigates the impact of factors responsible for quantitative and functional outcome after NSS.Patients and Methods:Fifty-two patients of localized renal mass (≤7 cm) were included in the study. A contrast-enhanced computed tomography abdomen was performed for characterization of tumor. Glomerular filtration rate (GFR) was calculated using Tc99m-diethylenetriamine pentaacetic acid (DTPA) scan and Cockcroft-Gault (CG) formula. All relevant intra- and peri-operative events were noted. Follow-up work up performed at 3 months.Results:Overall, the mean ischemia time was 30.6 min, with 7.7% decrease in renal volume in the operated moiety. In follow-up, the total and ipsilateral GFR decreased. Change in renal parenchymal volume, total GFR by CG and DTPA, split GFR of tumor-bearing moiety was significant in follow-up. Size, stage, polar location of tumor, duration of surgery, type of ischemia, preoperative chronic kidney disease, and need of blood transfusion did not affect change in renal volume and function in the follow-up period.Conclusion:Renal parenchymal loss and duration of ischemia have impact on the follow-up renal function.

PD07-11 TUMOR CONTACT SURFACE AREA AS A PREDICTOR OF FUNCTIONAL OUTCOMES AFTER PARTIAL NEPHRECTOMY

You have accessJournal of UrologyKidney Cancer: Localized: Surgical Therapy I1 Apr 2018PD07-11 TUMOR CONTACT SURFACE AREA AS A PREDICTOR OF FUNCTIONAL OUTCOMES AFTER PARTIAL NEPHRECTOMY Chalairat Suk-Ouichai, Wen Dong, Jitao Wu, Hajime Tanaka, JJ H. Zhang, Elvis R. Caraballo, Erick Remer, Jianbo Li, Sudhir Isharwal, and Steven C. Campbell Chalairat Suk-OuichaiChalairat Suk-Ouichai More articles by this author , Wen DongWen Dong More articles by this author , Jitao WuJitao Wu More articles by this author , Hajime TanakaHajime Tanaka More articles by this author , JJ H. ZhangJJ H. Zhang More articles by this author , Elvis R. CaraballoElvis R. Caraballo More articles by this author , Erick RemerErick Remer More articles by this author , Jianbo LiJianbo Li More articles by this author , Sudhir IsharwalSudhir Isharwal More articles by this author , and Steven C. CampbellSteven C. Campbell More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2018.02.444AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES New baseline glomerular filtration rate (GFR) can be a major factor for cancer survivorship after renal cancer surgery. Parenchymal mass preservation is the predominant factor associated with functional outcomes after partial nephrectomy (PN). Contact surface area (CSA) between the tumor and parenchyma may impact parenchymal preservation and predict functional outcomes after PN. We evaluated CSA as a predictor of parenchymal mass and function preserved by PN. METHODS 419 patients managed with PN had necessary studies to evaluate preoperative and postoperative parenchymal mass and renal function within the operated kidney. Patients with multifocal renal masses were excluded. Parenchymal mass in the operated kidney and CSA were measured using contrast-enhanced CT within 2 months prior to and 3-12 months after PN. CSA was calculated using mathematical formula: 2πrd, where r=radius and d=intraparenchymal depth of tumor. Pearson correlation evaluated relationships between CSA and parenchymal mass or GFR preservation. Multivariable linear regression assessed predictors for GFR preservation. Conceptually, the formula for CSA should function best for exophytic tumors, while predictive value for endophytic tumors may not be as strong. RESULTS Median tumor size and R.E.N.A.L. were 3.5 cm and 8, respectively. Median global and ipsilateral GFR preserved were 89% and 79%, respectively. Median ipsilateral parenchymal mass preserved was 85% and significantly higher for exophytic masses (87% vs 83%, p=0.001). Median CSA was 22.8cm2 and significantly less for exophytic masses (19.8cm2 vs 24.6cm2, p=0.02). CSA associated modestly with both ipsilateral GFR and mass preserved (r=0.25 and 0.36, respectively, both p<0.001). On multivariable analysis, CSA associated with ipsilateral GFR preserved for exophytic masses (p=0.011), but not for endophytic ones (p=0.27). Limitations include retrospective design. CONCLUSIONS CSA, which can be estimated preoperatively, associates with parenchymal mass and function saved after PN, although its utility appears to be greatest for exophytic rather than endophytic tumors. Further study will be required to validate the utility of CSA in different clinical settings. © 2018FiguresReferencesRelatedDetails Volume 199Issue 4SApril 2018Page: e160-e161 Advertisement Copyright & Permissions© 2018MetricsAuthor Information Chalairat Suk-Ouichai More articles by this author Wen Dong More articles by this author Jitao Wu More articles by this author Hajime Tanaka More articles by this author JJ H. Zhang More articles by this author Elvis R. Caraballo More articles by this author Erick Remer More articles by this author Jianbo Li More articles by this author Sudhir Isharwal More articles by this author Steven C. Campbell More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Tumor Contact Surface Area As a Predictor of Functional Outcomes After Standard Partial Nephrectomy: Utility and Limitations

To evaluate contact surface area (CSA) between the tumor and parenchyma as a predictor of ipsilateral parenchyma and function preserved after partial nephrectomy (PN). Previous studies suggested that CSA is a strong predictor of functional outcomes but the limitations of CSA have not been adequately explored. Four hundred nineteen patients managed with standard PN for solitary tumor with necessary studies to evaluate and analyze ipsilateral preoperative or postoperative parenchymal mass and function. Parenchymal mass and CSA were measured using contrast-enhanced computed tomography <2 months prior and 3-12months after PN. CSA was calculated: 2πrd, where r = radius and d = intraparenchymal depth. Pearson-correlation evaluated relationships between CSA and ipsilateral parenchymal mass or function preserved. Multivariable regression assessed predictors of function preserved. Conceptually, the CSA paradigm should function better for exophytic tumors than endophytic ones. Median tumor size was 3.5 cm and R.E.N.A.L. was 8. Median global and ipsilateral glomerular filtration rate preserved were 89% and 79%, respectively. Median ipsilateral parenchymal mass preserved was 85% and significantly higher for exophytic masses (P = .001). Median CSA was 22.8 cm2 and significantly less for exophytic masses (P = .02). CSA associated with both ipsilateral function and mass preserved (both P < .05), but the correlations were only modest (r = 0.25 and 0.36, respectively). On multivariable analysis, CSA associated with function preserved for exophytic masses (P = .01), but not for endophytic ones (P = .27). CSA associates with functional outcomes after standard PN, although the strength of the correlations was modest, unlike previous studies, and CSA was not an independent predictor for endophytic tumors. Further study will be required to evaluate the utility of CSA in various clinical settings.

Impact of Comorbidities on Functional Recovery from Partial Nephrectomy

Parenchymal mass preservation, and ischemia type and/or duration can influence functional recovery after partial nephrectomy. Some groups have hypothesized that relevant comorbidities may also impact nephron stability and functional recovery but this has not been adequately investigated. At our center 405 patients treated with partial nephrectomy from 2007 to 2015 had the necessary data to determine the function and parenchymal mass preserved in the ipsilateral kidney. Comorbidities potentially associated with renal functional status were reviewed, including various degrees of hypertension, diabetes, cardiovascular disease, obesity, smoking status and related medications. Multivariable linear regression was done to assess factors associated with functional recovery, defined as the percent of preserved ipsilateral glomerular filtration rate. Median tumor size was 3.5 cm and the median R.E.N.A.L. (radius, exophytic/endophytic properties, nearness of tumor to collecting system or sinus, anterior/posterior, location relative to polar lines and tumor touching main renal artery or vein) score was 8. Warm and cold ischemia were done in 264 (65%) and 141 patients for a median duration of 21 and 27 minutes, respectively. The median preserved ipsilateral glomerular filtration rate was 79%. Patient age, comorbidity index, hypertension and proteinuria were each associated with the preoperative glomerular filtration rate (all p <0.01). On univariable and multivariable analyses the preserved parenchymal mass, and ischemia type and duration were significantly associated with functional recovery (all p <0.001). On univariable analysis of comorbidities only hypertension was significantly associated with functional recovery. However, on multivariable analysis none of the analyzed comorbidities were associated with functional recovery. Recovery of function after partial nephrectomy depends primarily on parenchymal mass preservation and ischemia characteristics. Comorbidities failed to be associated with functional outcomes. Comorbidities can impact function, leading to surgery, and may influence long-term functional stability. However, our data suggest that they do not influence short-term recovery after partial nephrectomy.

MP59-09 FUNCTIONAL CHANGE OF CONTRALATERAL KIDNEY AFTER PARTIAL NEPHRECTOMY USING DIETHYLENE TRIAMINE PENTA-ACETIC ACID (DTPA) RENAL SCINTIGRAPHY: LONG TERM ANALYSIS

You have accessJournal of UrologyKidney Cancer: Localized: Surgical Therapy IV1 Apr 2017MP59-09 FUNCTIONAL CHANGE OF CONTRALATERAL KIDNEY AFTER PARTIAL NEPHRECTOMY USING DIETHYLENE TRIAMINE PENTA-ACETIC ACID (DTPA) RENAL SCINTIGRAPHY: LONG TERM ANALYSIS Se Young Choi, Jeman Ryu, Jae Hyeon Han, Wonchul Lee, Han Kyu Chae, Sangjun Yoo, Dalsan You, In Gab Jeong, Cheryn Song, Bumsik Hong, Hanjong Ahn, and Choung-Soo Kim Se Young ChoiSe Young Choi More articles by this author , Jeman RyuJeman Ryu More articles by this author , Jae Hyeon HanJae Hyeon Han More articles by this author , Wonchul LeeWonchul Lee More articles by this author , Han Kyu ChaeHan Kyu Chae More articles by this author , Sangjun YooSangjun Yoo More articles by this author , Dalsan YouDalsan You More articles by this author , In Gab JeongIn Gab Jeong More articles by this author , Cheryn SongCheryn Song More articles by this author , Bumsik HongBumsik Hong More articles by this author , Hanjong AhnHanjong Ahn More articles by this author , and Choung-Soo KimChoung-Soo Kim More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2017.02.1825AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Partial nephrectomy aims to maintain renal function by nephron sparing. However, the functional change of contralateral kidney remains to be known. We evaluated the functional change in contralateral kidney using DTPA renal scan and determined the predicting factors of contralateral kidney function after partial nephrectomy. METHODS From 2001 to 2012, 699 patients underwent partial nephrectomy and we performed DTPA renal scan before and after surgery in all patients to assess the exact renal function of each kidney. Patients were divided into 3 groups according to initial contralateral glomerular filtration rate (GFR) (group 1: <30ml/min/1.73m2, group 2: 30~45ml/min/1.73m2, and group 3: ≥45ml/min/1.73m2). We evaluated separate renal functions using DTPA up to 5 year after surgery. Logistic regression analysis was used to identify the factors associated with increased GFR of contralateral kidney. Kaplan-Meier method was used for overall survival. Median follow-up period was 45.1 month. RESULTS Patients of group 1 were older age (64.2±9.8 vs 55.0±11.0 vs 48.0±9.5, p<0.001), more hypertension history (59.5% vs 39.3% vs 20.9%, p<0.001), worse American society of anesthesiologists (ASA) score (≥2; 94.0% vs 89.5% vs 80.2%, p<0.001), and shorter ischemic time (19.9±8.0 vs 22.3±8.7 vs 22.8±8.9, p=0.025) among three groups (respectively). Tumor size, resected weight, RENAL nephrometry score and ischemic type were not different among three groups (p=0.293, p=0.255, p=0.582 and p=0.967, respectively). The mean ipsilateral GFR changes were -7.5%, -1.6%, and -21.2% in group 1, 2, and 3, respectively and contralateral GFR changes were 33.9%, 19.9%, and 7.3% in group 1, 2, and 3, respectively at 5 year after partial nephrectomy. On multivariable analysis, ASA score (OR 0.54, 95% confidence interval [CI] 0.31-0.92 p=0.0277) and preoperative contralateral GFR (OR 0.97, 95% CI 0.95-0.99 p=0.0011) were the significant predictive factors for increased GFR of contralateral kidney within 5 years. 5 year overall survival rates were 86.1%, 93.1% and 97.4% in group 1, 2, 3, respectively. CONCLUSIONS Contralateral kidney compensated for the functional loss of ipsilateral kidney. The increase of GFR in contralateral kidney is more prominent in healthy patients with decreased contralateral renal function. © 2017FiguresReferencesRelatedDetails Volume 197Issue 4SApril 2017Page: e784 Advertisement Copyright & Permissions© 2017MetricsAuthor Information Se Young Choi More articles by this author Jeman Ryu More articles by this author Jae Hyeon Han More articles by this author Wonchul Lee More articles by this author Han Kyu Chae More articles by this author Sangjun Yoo More articles by this author Dalsan You More articles by this author In Gab Jeong More articles by this author Cheryn Song More articles by this author Bumsik Hong More articles by this author Hanjong Ahn More articles by this author Choung-Soo Kim More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Excised Parenchymal Mass During Partial Nephrectomy: Functional Implications

To evaluate whether excised parenchymal mass (EPM) during partial nephrectomy (PN) correlates with functional decline and can serve as a surrogate for functional outcomes. All 215 patients managed with PN for unifocal renal mass with necessary studies to determine EPM and percent glomerular filtration rate (GFR) and parenchymal mass preserved (both global and specific to the operated kidney) were analyzed. EPM was estimated from the pathologic specimen by subtracting the tumor mass from the specimen mass, with both calculated using the elliptical formula. Vascularized parenchymal mass preserved was measured from computed tomography scans obtained <2 months prior and 3-12 months after surgery. All functional analyses were required to be within the same time frames, and patients with a contralateral kidney were also required to have nuclear renal scans. The median tumor size was 3.5 cm and the median R.E.N.A.L. was 7. Warm and cold ischemia were utilized in 123 and 92 patients, respectively (median ischemia time = 23 minutes). The median global GFR preserved was 89%, the median total parenchymal mass preserved was 93%, and the median estimated EPM was 16 cm3. Whereas percent parenchymal mass preserved correlated strongly with global and ipsilateral GFR preserved (both P < .001), EPM failed to correlate with functional outcomes on both univariable and multivariable analyses. Our data suggest that parenchymal mass preserved with standard PN by experienced surgeons associates strongly with function preserved, whereas EPM fails to correlate with functional outcomes. Further study of the functional impact of EPM in other circumstances will be required, such as enucleation or PN performed by less-experienced surgeons.

Preoperative planning and real-time assisted navigation by three-dimensional individual digital model in partial nephrectomy with three-dimensional laparoscopic system.

To evaluate the feasibility and effectiveness of preoperative planning and real-time assisted surgical navigation for three-dimensional laparoscopic partial nephrectomy under the guidance of three-dimensional individual digital model (3D-IDM) created using three-dimensional medical image reconstructing and guiding system (3D-MIRGS). Between May 2012 and February 2014, 44 patients with cT1 renal tumors underwent retroperitoneal laparoscopic partial nephrectomy (LPN) using a three-dimensional laparoscopic system. The 3D-IDMs were created using the 3D-MIRGS in 21 patients (3D-MIRGS group) between February 2013 and February 2014. After preoperative planning, operations were real-time assisted using composite 3D-IDMs, which were fused with two-dimensional retrolaparoscopic images. The remaining 23 patients underwent surgery without 3D-MIRGS between May 2012 and February 2013; 14 of these patients were selected as a control group. Preoperative aspects and dimensions used for an anatomical score, "radius; exophytic/endophytic; nearness; anterior/posterior; location" nephrometry score, tumor size, operative time (OT), segmental renal artery clamping (SRAC) time, estimated blood loss (EBL), postoperative hospitalization, the preoperative serum creatinine level and ipsilateral glomerular filtration rate (GFR), as well as postoperative 6-month data were compared between groups. All the SRAC procedures were technically successful, and each targeted tumor was excised completely; final pathological margin results were negative. The OT was shorter (159.0 vs. 193.2 min; p < 0.001), and EBL (148.1 vs. 176.1 mL; p < 0.001) was reduced in the 3D-MIRGS group compared with controls. No statistically significant differences in SRAC time or postoperative hospitalization were found between the groups. Neither group showed any statistically significant increases in serum creatinine level or decreases in ipsilateral GFR postoperatively. Preoperative planning and real-time assisted surgical navigation using the 3D-IDM reconstructed from 3D-MIRGS and combined with the 3D laparoscopic system can facilitate LPN and result in precise SRAC and accurate excision of tumor that is both effective and safe.

Clinical analysis of Habib 4X bipolar radiofrequency ablation assisted laparoscopic partial nephrectomy without blockage of renal artery

Objective To explore the clinical effect of Habib 4X bipolar radiofrequency ablation assisted laparoscopic partial nephrectomy without blockage of renal artery for treatment of renal cell carcinoma (RCC). Methods Between October 2010 and June 2011, 14 patients with exophytic RCC (T1N0M0) were treated with Laparoscopic Partial Nephrectomy with (LRA) or without (LPN) Habib 4X Bipolar Radiofrequency ablation assisted.The LRA group included 6 patients,and the maximum tumor diameter was 2.1 - 3.5 cm (mean,3.1 cm).The LPN group included 8 patients,and the maximum tumor diameter was 2.0 -3.7 cm (mean,3.0 cm).The operative time,average intra-operative blood loss,postoperative hospital stay and incidence of postoperative complications were recorded.Changes of hemoglobin (Hb),serum creatinine (SCr) and ipsilateral glomerular filtration rate (GFR) before and after operation were analyzed and compared. Results The 14 surgical procedures were successful without conversion to open operation.In LRA group,renal artery blocking was unnecessary,the Hb,SCr and GFR before and after operation were (127 ± 19) g/L vs.(124 ± 19) g/L、(96 ±39) μmol/L vs.(92 ±29) μmol/L and (42 ± 12) ml/min vs.(40 ± 13) ml/min,respectively,and the difference was not significant (P ＞0.05).In LPN group,the renal artery blocking time was 20-52 min (mean,32 min),the Hb,SCr and GFR before and after operations were (130±17) g/L vs.(112±15) g/L,(92 ±31) μ mol/L vs.(110±28)μmol/L and (43 ± 14) ml/min vs.(30 ± 11 ) ml/min respectively,and the difference was significant (P ＜0.05 ).The operative time was ( 86 ± 20) min and ( 112 ± 43 ) min,the estimated blood loss was (94 ± 18)ml and (256 ± 58) ml,and the postoperative hospital stay was (5.0 ± 0.8) d and (7.8 ± 1.2 ) d,respectively.The difference between the two groups was significant (P ＜ O.05).Complications such as bleeding,gross hematuria,and leakage of urine were noted in LRA group. Conclusions Habib 4X Bipolar Radiofrequency ablation assisted LPN without blockage of renal artery is a safe and effective intervention with a relatively low incidence of complications.And it is superior to LPN in operative time,intraoperative blood loss and postoperative recovery. Key words: Renal tumor; Partial Nephrectomy; Laparoscopy; Radiofrequency ablation

Is 2-Week Duration Sufficient for Stenting in Endopyelotomy?

Internal stenting is an integral part of endopyelotomy. Studies in animals show good healing after 1 to 2 weeks of ureterotomy. Inherent stent related problems warrant a minimum possible duration of stenting without compromising the results of endopyelotomy. We performed a prospective randomized trial to evaluate the optimum duration of stenting after endopyelotomy. A total of 57 consecutive patients with primary ureteropelvic junction obstruction were randomized to undergo 7/14Fr internal endopyelotomy stent placement for 2 (group 1) and 4 (group 2) weeks. A symptom based questionnaire was administered to all patients at stent removal. Followup was done with diuretic scanning at 3, 6, 9 and 12 months and then yearly, and thereafter with diuretic renography. In each group 26 patients were available for evaluation. The 2 groups were comparable in terms of age, sex, symptoms and ipsilateral glomerular filtration rate. Mean followup was 22.3 (range 12 to 36) and 21.3 months (range 12 to 35) in groups 1 and 2, respectively. At the end of 1 year 24 group 1 (92.3%) and 23 group 2 (90.3%) patients had an improved drainage pattern. This difference was not significant. Stent related symptoms were present in a good proportion of patients in groups 1 and 2 but there was a significant difference in the incidence of urinary tract infections (11.5% versus 38.1%, p = 0.04). Of the group 2 patients 64% preferred 2 weeks of stenting. Two weeks seems to be a sufficient duration to allow functional restoration across the ureteropelvic junction after endopyelotomy and decrease stent related complications.