Nephron-sparing Surgery Group Research Articles

Pathological Insights into Non-Neoplastic Renal Parenchyma in Wilms Tumor: Implications for Nephron-Sparing Surgery.

This study aimed to evaluate the non-neoplastic renal parenchyma in Wilms tumor (WT) and investigate its impact on nephron-sparing surgery (NSS). The non-neoplastic renal parenchyma of WT patients was prospectively collected for pathological examination. The histology of non-neoplastic renal parenchyma was assessed from two perspectives: nephrogenic rests (NRs) and nephrons. A total of 46 non-neoplastic renal parenchyma specimens were collected from 42 WT patients. The surgeons assessed the median proportion of non-neoplastic renal parenchyma as 30%, whereas using ellipsoid volume, it was calculated to be 27%. The Youden index of surgeons' assessment peaked at a 15% proportion of non-neoplastic renal parenchyma. The bilateral WT (BWT) group and NSS group exhibited significant differences compared with the unilateral WT group and radical nephrectomy group, respectively, with the BWT group showing a tendency toward thickened basement membrane. The presence of NRs and endogenous nephron alternations should be given due attention in WT. The probability of abnormalities is low when the proportion of non-neoplastic renal parenchyma exceeds 15%, providing pathological support for expanding the adaptation of NSS.

The safety and effectiveness of laparoscopic off-clamp tumor evacuation versus traditional nephron-sparing surgery for large (>4 cm) sporadic renal angiomyolipomas

BackgroundOff-clamp nephron-sparing surgery (NSS) have been selectively performed in renal tumors in which the majority are T1a (<4 cm) renal caners. Less is known, however, whether off-clamp is a safe and effective option for treatment of Sporadic Renal Angiomyolipomas (RAML), especially in those >4 cm. The objective of our study was to compare the perioperative and renal function outcomes of a novel off-clamp tumor evacuation technique versus conventional laparoscopic NSS for the treatment of large sporadic RAMLs (>4 cm). MethodsFrom January 2021 to June 2022, 42 patients diagnosed with RAML were prospectively randomized to receive laparoscopic standard NSS (Group 1) and off-clamp tumor evacuation (Group 2). The surgical and postoperative outcomes of both groups were compared. ResultsBaseline characteristics demonstrated no discernible variation between Group 1 and Group 2. Compared to Group 1, Group 2 was associated shorter operative time (92.5 vs 82.3 min, p < 0.001), elimination of warm ischemic time (22.9 vs 0 min, p < 0.001), more blood loss (92.6 vs 161.9 ml, p = 0.02), and lower short-term renal function reduction of the operated kidney (17.2% vs 9%; p < 0.001). Neither major complication nor recurrence occurred. ConclusionIt seems that transperitoneal laparoscopic off-clamp tumor evacuation is a feasible and safe option for the treatment of RAML, with the added benefit of preserving renal function to a greater extent than the traditional methods.

A radiomics nomogram for preoperative prediction of nephron-sparing surgery in patients with bilateral Wilms tumor.

Bilateral Wilms tumor (BWT) is a relatively rare malignant renal tumor in children. Nephron-sparing surgery (NSS) is the preferred surgical approach for treating BWT, but lacks uniform surgical indications worldwide. This study aimed to summarize the clinical and imaging features of BWT children, establish a radiomics nomogram, and predict the feasibility of NSS for improving outcomes. A 12-year retrospective single-center review was conducted on clinical data and preoperative imaging features of BWT patients. The tumor kidneys were divided into NSS and non-NSS groups. Logistic regression analysis was performed to identify independent predictors and develop a prediction model of the feasibility of NSS in BWT patients. A radiomics nomogram was constructed and internally validated by the parametric bootstrapping method. A total of 58 BWT patients (115 renal units) were included in this study. After evaluations based on preoperative imaging and clinical data, 94 renal units underwent NSS with negative resection margins and were included in the NSS group, whereas 16 renal units with positive resection margins, macroscopic residual, or total nephrectomies were included in the non-NSS group. Tumor size [odds ratio (OR): 0.540, 95% confidence interval (CI): 0.308-0.945], relationship with the collecting system (OR: 0.013, 95% CI: 0.0004-0.370), and remaining renal parenchyma (RRP) proportion (OR: 71.23, 95% CI: 1.632-3108.8) were identified as independent predictors for NSS. A nomogram was constructed based on these factors, which demonstrated great consistency between the predicted and observed feasibility of NSS. The model presented with good discriminative ability [area under the curve (AUC), 0.982]. The decision curve analysis (DCA) revealed the clinical usefulness of the model. This study analyzed the clinical and preoperative imaging data of BWT patients and identified three independent predictors for the feasibility of NSS, including tumor size, relationship with the collecting system, and residual renal parenchyma proportion. The radiomics nomogram established in this study can provide individualized predictions to assist clinicians in making better decisions and improving patient outcomes.

Renal function and survival following treatment for cT1N0 renal cell carcinoma in a veteran population.

642 Background: Radical nephrectomy (RN), nephron sparing surgery (NSS) and thermal ablation (TA) are associated with similar oncologic control for early-stage renal cell carcinoma (RCC). However, the potential protective role of nephron sparing treatments on renal function and its impact on non-cancer related mortality remains undetermined. Methods: We employed the national Veterans Affairs Corporate Data Warehouse (CDW) to identify patients diagnosed with cT1N0 RCC between 2000-2018. Laboratory and diagnosis data were used to calculate creatinine clearance and Charlson comorbidity score. Chronic kidney disease (CKD) was defined as creatinine clearance &lt; 60 milliliters per minute. Kaplan-Meier analysis and multivariable Cox regression analysis were used to evaluate overall survival. Results: Overall, there were 8279 Veterans with cT1N0M0 renal cell carcinoma diagnosed between 2000-2018 who received either RN (2946, 36%), NSS (4846, 59%) or TA (487, 6%). Median follow up time was 8 years (90% CI 2-15 years). Patients receiving RN were older than those receiving NSS (median age 64.0 vs 62.6 years, p&lt;0.01) but younger than those receiving TA (median age 67.9 years, p&lt;0.01). Patients receiving RN and TA had more comorbidities than patients receiving NSS (mean Charlson scores 0.76 vs. 1.00 vs. 0.66, p&lt;0.01. More patients among the RN group had CKD before RCC diagnosis than the NSS and TA groups (10% vs. 6% vs. 7%, p&lt;0.01). Among the subset of patients without CKD before treatment, 17% of RN, 8% of NSS, and 11% of TA developed CKD at least 1 year after treatment, (p &lt;0.01). Median OS was 11.5 years with RN, 14.2 years with NSS, and 10.3 years with TA. On multivariable analysis considering age, comorbidities, CKD, race, and year of treatment, compared to RN, NSS was associated with better OS (HR 0.75, p&lt;0.01) with a trend to improved survival with TA (HR 0.88, p=0.08). Conclusions: NSS or TA are associated with less post-operative renal dysfunction than RN in patients treated for cT1N0 RCC in the VAHCS. NSS is associated with improved OS compared to RN. Further studies are warranted to assess the impact of renal dysfunction in this population in relation to oncologic and survival outcomes.

Erythropoietin Preconditioning Mobilizes Endothelial Progenitor Cells to Attenuate Nephron-Sparing Surgery-Induced Ischemia-Reperfusion Injury

The purpose of this study was to examine the role of endothelial progenitor cells (EPCs) in protection against ischemic-reperfusion injury (IRI) in a nephron-sparing surgery (NSS) rat model using erythropoietin (EPO) preconditioning. Fifty-four male Sprague-Dawley rats were randomly divided into 3 groups for right kidney nephrectomy treatment: sham group (exposure without clamp treatment), NSS group (3 days of peritoneal phosphate buffered saline [PBS] injection before renal blood vessels were clamped for 40 mins and NSS was performed), and EPO group (3 days of EPO abdomen injections prior to renal blood vessel clamping for 40 min before NSS was performed). After 12, 24, and 72 hours, inferior vena cava blood and renal tissues were harvested. The extent of renal injury was assessed, along with EPC number, cell proliferation, angiogenesis, and vascular growth factor expression. EPO preconditioning significantly improved renal function and histologic morphology, indicated by reduced blood urea nitrogen (BUN) ([33.12 ± 1.88] vs [16.03 ± 0.91], P < .05) and serum creatinine (Scr) ([190.2 ± 20.23] vs [77.23 ± 5.82], P < .05) levels and histologic injury scores ([3.20 ± 0.78] vs [1.70 ± 0.67], P < .05). Angiogenesis in peritubular capillaries markedly increased in the EPO group. EPC numbers increased in the kidneys at 24 hours following reperfusion in the EPO group, compared to the NSS group. Furthermore, EPO preconditioning also increased SDF-1α and CXCR7 expression at 24 hours following reperfusion relative to the NSS group. These findings suggest that EPO pretreatment can reduce renal injury in rats caused by IRI. Mechanistically, this may be related to EPC mobilization and recruitment to injured renal tissues by SDF-1α and CXCR7.

Role of preoperative MR volumetry in patients with renal cell carcinoma for prediction of postoperative renal function after radical nephrectomy and nephron sparing surgery.

ABSTRACTPurpose Preoperative computed tomography or magnetic resonance (MR) imaging are commonly used for radiological evaluation of renal cell carcinoma (RCC) before radical nephrectomy or nephron sparing surgery(NSS). This study aimed to assess the role of MRI for predicting postoperative renal function by preoperative estimation of renal parenchymal volume and correlation with glomerular filtration rate (GFR).Materials and Methods A prospective observational study was conducted from February 2015 to October 2016 at a tertiary care hospital in northern India. MR imaging was done on 3 Tesla MR scanner (Signa Hdxt General Electrics, Milwaukee, USA). MR volumetry was used to estimate the renal parenchymal volume. GFR was measured in all patients using Tc99m Diethyl-triamine-penta-acetic acid using Russell’s algorithm. Such measurement was done preoperatively, and postoperatively 3 months after surgery.Results 30 patients with suspected RCC underwent NSS (n=10) and radical nephrectomy (n=20). Median tumour volume was 175.7cc (range: 4.8 to 631.8cc). The median volume of the residual parenchyma on the affected side was 84.25±41.97cc while that on the unaffected side was 112.25±26.35cc. There was good correlation among the unaffected kidney volume and postoperative GFR for the radical nephrectomy group (r=0.83) as well as unaffected kidney volume, total residual kidney volume and residual volume of affected kidney with postoperative GFR for the NSS group (r=0.71, r=0.73, r=0.79 respectively; P <0.05).Conclusion Preoperative residual parenchymal volume on MR renal volumetry correlates well with postoperative GFR in patients with RCC undergoing radical nephrectomy or NSS.

Evaluation of Nephron-Sparing Surgery as Potential Risk Factor for Relapse in Unilateral Wilms Tumor

BackgroundThe aim of the study was to assess the prognostic significance of nephron-sparing surgery (NSS) without tumor size limits as a risk factor for relapse in children with unilateral Wilms Tumor (WT). MethodsA 28-y retrospective single-center review was performed. Prognostic relevance of age, gender, stage, histology, nephrectomy (N), and NSS was analyzed. ResultsSixty-nine cases (42 females and 27 males) with WT, off-therapy from 21 to 325 mo after chemotherapy mainly based on the International Society of Pediatric Oncology trials, were treated at our institution. Five cases were excluded (three children with synchronous bilateral WT and two adults with unilateral WT). Of 64 children with unilateral WT, 51 underwent N and 13 NSS without tumor size limits. Indeed, two-thirds of children who underwent NSS presented with a tumor diameter >4 cm. Overall, nine patients (14%) had a relapse (male-to-female ratio = 1:8). Initial surgery was N in eight cases and NSS in another one. Relapse rates in N and NSS groups were 15.7% and 7.7% (P = nonsignificant), respectively; the relapse rates in N and NSS groups were 8.6% and 7.7% (P = nonsignificant) for stages I-II unilateral WT cohort, respectively. On univariate analysis, factors correlated with probability of relapse were unfavorable histology (P < 0.002) and stage III disease (P < 0.01). ConclusionsIn unilateral WT, NSS, whenever feasible, does not seem to increase the risk of recurrence. A multicenter prospective trial is required to carefully evaluate this risk.

Role of MRI in staging and surgical planning and its clinicopathological correlation in patients with renal cell carcinoma.

Background and Aims:Radiological evaluation of renal cell carcinoma (RCC) is used for non-invasive staging for better surgical planning. However, the correlation of radiological staging using magnetic resonance imaging (MRI) with histopathological findings has not been done so far. The aim of this study is to assess the role of MRI in pre-operative staging of RCC in patients undergoing radical nephrectomy and nephron sparing surgery (NSS) and correlate it with histopathological findings.Settings and Design:This prospective observational study was conducted from February 2015 to October 2016 at a tertiary care hospital in northern India.Methods:MR imaging was done on 3 Tesla MR scanner (Signa Hdxt General Electrics, Milwaukee, USA). Preoperative staging was based on 2010 TNM staging system. The preoperative parameters in MRI were tumor size, detection/breach of pseudocapsule, tumor extension into perirenal fat and detection of tumor venous thrombus. The staging on MRI was compared with surgical and pathological staging.Statistical Analysis Used:The agreement between these three staging methods was determined using the kappa statistics (0.0-0.2, poor; 0.2-0.4, fair; 0.4-0.6, moderate; 0.6-0.8, good; 0.8-1.0, excellent).Results:30 patients with suspected RCC underwent NSS (n = 10) and radical nephrectomy (n = 20). Mean tumor size was 9.66 ± 2.99 cm in the radical nephrectomy group and 4.06 ± 1.16 cm in the NSS group. There was perfect agreement between MRI, surgical and pathological staging for breach of pseudocapsule (κ =1.0, Percentage of Agreement = 100%, P < 0.05). In none of the patients, MRI missed extension beyond the Gerota's fascia or presence of venous thrombus.Conclusion:MRI staging of RCC is an accurate predictor of the surgical and pathological stage and has the potential to become a useful tool for preoperative identification of patients with RCC who can undergo NSS.

Survival outcomes in patients with large (≥7cm) clear cell renal cell carcinomas treated with nephron-sparing surgery versus radical nephrectomy: Results of a multicenter cohort with long-term follow-up.

BackgroundDoes the dogma of nephron sparing surgery (NSS) still stand for large renal masses? Available studies dealing with that issue are considerably biased often mixing imperative with elective indications for NSS and also including less malignant variants or even benign renal tumors. Here, we analyzed the oncological long-term outcomes of patients undergoing elective NSS or radical tumor nephrectomy (RN) for non-endophytic, large (≥7cm) clear cell renal carcinoma (ccRCC).MethodsProspectively acquired, clinical databases from two academic high-volume centers were screened for patients from 1980 to 2010. The query was strictly limited to patients with elective indications. Surgical complications were retrospectively assessed and classified using the Clavien-Dindo-classification system (CDS). Overall survival (OS) and cancer specific survival (CSS) were analyzed using the Kaplan-Meier-method and the log-rank test.ResultsOut of in total 8664 patients in the databases, 123 patients were identified (elective NSS (n = 18) or elective RN (n = 105)) for ≥7cm ccRCC. The median follow-up over all was 102 months (range 3–367 months). Compared to the RN group, the NSS group had a significantly longer median OS (p = 0.014) and median CSS (p = 0.04).ConclusionsIn large renal masses, NSS can be performed safely with acceptable complication rates. In terms of long-term OS and CSS, NSS was at least not inferior to RN. Our findings suggest that NSS should also be performed in patients presenting with renal tumors ≥7cm whenever technically feasible. Limitations include its retrospective nature and the limited availability of data concerning long-term development of renal function in the two groups.

The safety and efficacy of nephron sparing surgery in T1N0M0 renal cell carcinoma

Background: Renal cell carcinoma (RCC) accounts for approximately 3% of adult malignancies and 90-95% of neoplasm arising from the kidney. Objective was to explore the safety and efficacy of nephron sparing surgery (NSS) for T1N0M0 renal cell carcinomas (RCC) and to assess the oncological outcome of NSS in T1N0M0 RCC.Methods: A total of 31 cases were enrolled for the study of which 11 (35.5%) underwent NSS and 20 (64.5%) underwent radical nephrectomy (RN). The clinical results were followed up and comparatively analyzed.Results: NSS was performed using a margin of 1cm, no positive surgical margin was detected. The mean blood loss and mean duration of surgery in NSS and RN was comparable. Among all one patient from NSS group experienced urinary leak which was managed by placement of DJ stent. The overall complication rate was 9.1% in NSS. Lab. tests before surgery and after surgery at 6month was done in the both groups and results obtained was within normal limits. Only one patient developed metastasis from NSS group and died at 14th month of fallow-up, whereas neither metastasis nor mortality were recorded in RN group.Conclusions: Nephron sparing SURGERY has proven to be a safe and effective approach for Renal cell carcinoma with comparable clinical results to radical nephrectomy especially in tumour ≤4cm.

End-Stage Renal Disease After Renal Surgery in Patients with Normal Preoperative Kidney Function: Balancing Surgical Strategy and Individual Disorders at Baseline

Although nephron-sparing surgery (NSS) has demonstrated benefit in terms of renal function preservation, it is unclear whether NSS might also decrease the risk of end-stage renal disease (ESRD) relative to radical nephrectomy (RN). In the current paper, we aimed to report the rate and the predictors of ESRD after surgery, accounting for detailed individual baseline characteristics and comorbidities. A multi-institutional collaboration among five European tertiary care centers allowed study of 2027 patients with normal preoperative renal function and a clinically localized T1abN0M0 renal mass. Cox regression analyses were used to predict the risk of ESRD (defined as the onset of a postoperative estimated glomerular filtration rate <15ml/min per 1.73 m2) after adjusting for the individual baseline risk of developing chronic kidney disease. Univariable ESRD rates at 5 and 10 yr of follow-up were virtually equivalent for patients who underwent NSS (1.5% and 2.5%, respectively) versus RN (1.9% and 2.7%, respectively; hazard ratio [HR]: 0.8; 95% confidence interval [CI], 0.4–1.6). However, diabetes, smoking, uncontrolled hypertension, and other comorbidities were consistently more frequent in the NSS group relative to their RN counterparts. After adjusting for detailed baseline individual characteristics, NSS was shown to have an independent protective effect relative to RN (HR: 0.4; 95% CI, 0.2–0.8; p=0.02) at multivariable analyses. Patient summaryAfter accounting for individual baseline characteristics, such as age, diabetes, uncontrolled hypertension, or other comorbidities, partial nephrectomy independently protects against end-stage renal disease and the consequent need for dialysis relative to radical nephrectomy.

Estimated functional renal parenchymal volume predicts the split renal function following renal surgery.

The change in functional renal volume (FRV) has an absolute influence on renal function after nephrectomy (Nx) or nephron-sparing surgery (NSS). In this study, we prospectively examined whether the postoperative renal function following Nx and NSS could be accurately predicted and assessed the reproducibility of our newly developed 3-D image reconstruction system (Kashihara) to measure the FRV. We enrolled 98 patients who underwent Nx and 41 patients who underwent NSS from April 2006 to September 2009 to predict postoperative FRV and renal function. FRV was measured before and after (1 month and 1 year) renal surgery. The postoperative estimated glomerular filtration rate (eGFR) was predicted from the preoperative eGFR calculated from the serum creatinine (sCr) level and the ratio of the postoperative/preoperative FRV. To assess the reproducibility and accuracy of our newly developed 3-dimensional (3-D) image reconstruction system, FRV was measured by five examiners using images obtained by CT (five cases) and MRI (five cases). Significant correlation was found both for FRV and for renal function between the predictive values and the actually measured values at 1 month and 1 year after surgery, not only in the Nx group, but also in the NSS group. The accuracy and reproducibility could be confirmed both with CT and MRI studies. The postoperative FRV and renal function could be predicted preoperatively using a 3-D image reconstructive system, preoperative routine diagnostic imaging, and preoperative sCr level.

Nephron sparing surgery (NSS) for unilateral wilms tumor (UWT): the SIOP 2001 experience.

Total nephrectomy (TN) remains the standard treatment of unilateral Wilms tumors (uWT). The SIOP WT-2001 protocol allowed Nephron Sparing Surgery (NSS) for polar or peripherally non-infiltrating tumors. Inventory of the current SIOP NSS-experience. 2,800 patients with a unilateral, localized or metastatic and an unequivocal surgical technique recorded were included. All had neo-adjuvant chemotherapy and delayed surgery. In 91 (3%) NSS was performed and in 2709 TN. Data was retrieved from the SIOP WT 2001 database. NSS group contained 65% stage I tumours and the TN group 48%. Tumor volume (at diagnosis and surgery) was significantly smaller in the NSS group. Within stage III, after NSS, 7/12 (58%) had positive margins (M +), 5 with tumor negative lymph nodes (LN-). After TN, 355/712 (55%) had M + , 182 were LN-. Treatment of M+ in the NSS group resulted in two conversions to TN (one combined with radiotherapy), three patients had radiotherapy only and in two patients local therapy, if given, was not recorded. After NSS, four recurrences occurred. For localized disease the 5-year overall (OS) and event free survival (EFS) in NSS group was 100 and 94.8 (95% CI:89.9-99.9), respectively, while OS and EFS in the TN group were 94.4 (95% CI: 93.2-95.5, log-rank test P = 0.06) and 86.5 (95% CI:85.0-88.1, log-rank test P = 0.06), respectively. NSS was only performed in 3% of patients with uWT. Despite excellent survival with few relapses, the gain of nephrons needs to be weighed against the risk to induce stage III with intensified therapy.

Nephron-Sparing Surgery

Renal cell carcinoma (RCC) is a common malignancy with an increasing incidence.1 2 The classic triad of abdominal mass, hematuria, and flank pain accompanied by the various associated paraneoplastic syndromes (or the “internist's tumor”) are rare presentations of contemporary kidney cancer. With the current use and practice of modern abdominal imaging, more than half of all renal tumors are incidentally discovered at a low stage during evaluation for other conditions. The renal mass has become increasingly amenable to treatment given this stage migration. Therefore, in the modern era, it might be more appropriate to refer to RCC as the “radiologist's tumor” rather than the internists. The International Union Against Cancer staging system for RCC defines a stage 1 renal mass as an organ-confined tumor up to 4.0 cm in diameter (T1a), and between 4.1 and 7.0 cm in diameter (T1b). The American Urological Association (AUA) published guidelines for the management of stage 1 renal mass in 2009 and had validity confirmed in 2010.3 The AUA's thorough review is a must read for any practitioner treating renal masses. The National Comprehensive Cancer Network (NCCN) also provides guidance on the management of stage 1 renal masses.4 In this review, a small renal mass (SRM) is considered a T1a renal mass. The majority of SRMs will be RCCs; however many, approximately 20% will have benign histology.5 Even many of those classified as kidney cancer may have an indolent clinical course with limited growth and low risk of metastasis.6 Malignant potential is an important consideration when contemplating the permanent removal of a renal unit. Stage 1 renal masses are often successfully treated with nephron-sparing surgery (NSS) and this is the preferred approach to the resectable SRM. For this article, NSS will include only surgical partial nephrectomy, but ablative therapies such as cryoablation and radiofrequency ablation are also successfully used to preserve renal tissue on an ipsilateral renal unit. NSS was proven feasible decades ago for patients with imperative indications to preserve maximum kidney function, for instance solitary kidney, bilateral renal tumors, or moderate/severe chronic kidney disease (CKD).7 This allowed for expansion of NSS into general use for the stage 1 renal mass. Pathologic studies have shown underlying renal disease is commonly present in presumably “normal” kidneys, and outcomes studies clearly demonstrate new CKD development after nephrectomy.8 CKD has been linked to cardiovascular disease, hospitalization, and death in a population-based study of more than 1 million patients.9 This study challenges the notion that the loss of a renal unit does not significantly impact long-term health outcomes. Unfortunately NSS is widely underutilized. An evaluation of a nationwide hospital database determined only 9% of patients with surgically treatable renal tumors were treated with NSS.7 There are varied reasons for the underuse of NSS; the complexity of the surgical endeavor, an under appreciation for the impact of radical nephrectomy (RN) on health outcomes, and peculiar financial incentives seem to contribute to underutilization. NSS does have more short-term complications compared with total nephrectomy, and the oncologic efficacy had not been proven in a randomized trial. Starting in 1992, the European Organization for Research and Treatment of Cancer (EORTC) attempted to perform a randomized trial of elective NSS and RN for renal masses 5 cm or smaller10; however, the study closed early due to poor accrual and has raised many statistical questions. The published data, however, should be carefully considered, and one safe conclusion from the trial is that both RN and NSS provide excellent oncologic control. There were more local recurrences (albeit few in total) in the NSS group.

Comparison of Long-Term Results After Nephron-Sparing Surgery and Radical Nephrectomy in Treating 4- to 7-cm Renal Cell Carcinoma

The aim of our study was to compare long-term oncological outcomes following nephron-sparing surgery (NSS) and radical nephrectomy (RN) for renal cell carcinoma (RCC) 4 to 7 cm in diameter. The study included patients who underwent RN or NSS for RCC 4 to 7 cm in diameter between 1998 and 2009. The studied groups were compared with respect to the patients' age, sex, physical status according to the American Society of Anesthesiologists Physical classification, histological type, stage, tumor size, grade, duration of the operation, and complications. Survival was established using the Kaplan-Meier method. The risk factors for survival were analyzed using a multivariate Cox regression model. During the study, 351 patients underwent surgery: 317 patients (90.3%) underwent RN, and 34 (9.7%), NSS. The compared groups differed with respect to tumor size (P=0.001) and stage (P=0.006). The overall estimated 12-year survival was 53.7% after RN and 55.2% after NSS (log-rank test P=0.437). The 12-year cancer-specific survival in the RN and NSS groups was 69.6% and 80.6%, respectively (log-rank test P=0.198). Pathological stage and patients' age were the major factors affecting both overall and cancer-specific survival. The type of surgery (NSS or RN) had no effect on survival. Our study showed that nephron-sparing surgery is a safe technique compared with radical nephrectomy that ensures good oncological control in the treatment of renal cell carcinoma measuring 4 to 7 cm and may be proposed as the treatment of choice for renal tumors not only up to 4 cm, but also 4 to 7 cm in size.

Protective effect of endothelial progenitor cells mediated by ischemic preconditioning on renal ischemic injury induced by nephron sparing surgery

Objective To investigate the role of endothelial progenitor cells (EPCs) mediated by ischemic preconditioning (IPC) in renal ischemic injury in a nephron sparing surgery (NSS) rat model.Methods Ninety male Sprague-Dawley rats were randomly divided into three groups after right-side kidney nephrectomy.In sham-operated rats,lumbotomy without vascular clamping was performed; In NSS rats,renal blood vesses were clamped for 40 min and lower pole partial nephrectomy (PN) was performed; In NSS + IPC rats,besides pre-treatment with 15-min ischemia and 10-min reperfusion,the rest procedures were the same as those in NSS rats.At 1,3,6,12,24 h,and 3 days after reperfusion,the circulating pool and kidneys were harvested.The severity of renal injury,the home of EPCs,proliferation of endothelial cells as well as vascular growth factor expression was examined.Results Pretreated rats exhibited significant improvements in renal function and morphology.The histological score was significantly decreased in IPC group as compared with NSS group [(1.80 ± 0.45) vs.(3.00 ± 0.71),P ＜ 0.05].The number of EPCs in the kidneys was increased at 12 h after reperfusion in IPC group as compared with NSS groups [(5.75 ± 0.71) ％ vs.(2.92 ± 0.71) ％,P ＜ 0.05].Proliferation of EPCs in peritubular capillaries was markedly increased in the kidneys treated with IPC.In addition,the expression of vascular endothelial growth factor,and stromal cell-derived factor-1α in the kidneys of pretreated rats was increased as compared with that in rats subjected to ischemic injury (P ＜ 0.05).Conclusion IPC may attenuate renal ischemic injury induced by NSS; EPCs play an important role in renal protection,which involves promotion of endothelial cell proliferation through release of several angiogenic factors. Key words: Ischemic preconditioning; Endothelial progenitor cells; Nephron sparing surgery

Population‐based comparative effectiveness of nephron‐sparing surgery vs ablation for small renal masses

To determine, in a population-based cohort, if disease-specific survival (DSS) was equivalent in patients undergoing ablation vs nephron-sparing surgery (NSS) for clinical stage T1a renal cell carcinoma (RCC). A retrospective cohort study was performed using patients from the Surveillance, Epidemiology and End Results cancer registry with RCC < 4 cm and no evidence of distant metastases, who underwent ablation or NSS. Kaplan-Meier and Cox regression analyses were performed to determine if treatment type was independently associated with DSS. Between 1998 and 2007, a total of 8818 incident cases of RCC were treated with either NSS (7704) or ablation (1114). The median (interquartile range) follow-up was 2.8 (1.2-4.7) years in the NSS group and 1.6 (0.7-2.9) years in the ablation group, although 10% of each cohort were followed up beyond 5 years. After multivariable adjustment, ablation was associated with a twofold greater risk of kidney cancer death than NSS (hazard ratio 1.9, 95% confidence interval 1.1-3.3, P= 0.02). Age, gender, marital status and tumour size were also significantly associated with outcome. The predicted probability of DSS at 5 years was 98.3% with NSS and 96.6% with ablation. After controlling for age, gender, marital status and tumour size, the typical patient presenting with clinical stage T1a RCC, who undergoes ablation rather than NSS, has a twofold increase in the risk of kidney cancer death; however, at 5 years the absolute difference is small, and may only be realized by patients with long life expectancies.

1533 COMPARISON OF RATES AND RISK FACTORS FOR DEVELOPMENT OF ERECTILE DYSFUNCTION AFTER RADICAL OR PARTIAL NEPHRECTOMY

You have accessJournal of UrologySexual Function/Dysfunction/Andrology: Evaluation1 Apr 20111533 COMPARISON OF RATES AND RISK FACTORS FOR DEVELOPMENT OF ERECTILE DYSFUNCTION AFTER RADICAL OR PARTIAL NEPHRECTOMY Ryan Kopp, Jonathan Silberstein, Reza Mehrazin, Aditya Bagrodia, Robert Wake, Anthony Patterson, Jim Wan, and Ithaar Derweesh Ryan KoppRyan Kopp San Diego, CA More articles by this author , Jonathan SilbersteinJonathan Silberstein New York, NY More articles by this author , Reza MehrazinReza Mehrazin Memphis, TN More articles by this author , Aditya BagrodiaAditya Bagrodia Memphis, TN More articles by this author , Robert WakeRobert Wake Memphis, TN More articles by this author , Anthony PattersonAnthony Patterson Memphis, TN More articles by this author , Jim WanJim Wan Memphis, TN More articles by this author , and Ithaar DerweeshIthaar Derweesh San Diego, CA More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.1528AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Nephron Sparing Surgery (NSS) has emerged as a preferred treatment option for small renal masses, comparing favorably with radical nephrectomy (RN) from the standpoint of oncologic efficacy and conferring superior renal functional preservation. Erectile function may be affected by declining renal function. We examined the incidence of and risk factors for development of erectile dysfunction (ED) in patients who underwent RN and NSS. METHODS Retrospective review of 432 patients (264 RN/168 NSS, mean age 58 years, mean follow-up 5.8 years) who underwent RN or NSS for renal tumors at two institutions from 1/1998 to 12/2007. Demographics and disease characteristics, metabolic parameters [estimated Glomerular Filtration Rate (GFR), serum creatinine, hyperlipidemia, diabetes mellitus (DM)], pre- and postoperative ED (Sexual Health Inventory for Men score <22) and response rate to 5-phosphodiesterase inhibitor therapy (5-PDEi) were recorded in sexually active men. Data were analyzed within subgroups based on treatment (RN vs. NSS). Multivariate analysis (MVA) was conducted to elucidate risk factors for development of de novo ED. RESULTS RN and NSS groups had similar demographics and comorbidities. Tumor size (cm) was significantly larger for RN (RN 7.0 vs. NSS 3.7, p<0.001). No significant differences were observed for preoperative eGFR, hyperlipidemia, and DM. Significantly more preoperative ED existed in NSS vs. RN (p=0.042). Postoperatively, significantly higher rates of de novo DM (11.4% vs. 4.2%, p=0.015), eGFR<60 mL/min/1.73m2 (33.0% vs. 9.8%, p<0.001), and ED (29.5% vs. 9.5%, p<0.001) developed in RN vs. NSS cohorts, respectively. Overall response rate to 5-PDEi was 63% without significant difference between the two groups (p=0.896). MVA demonstrated RN (OR 3.56, p<0.001), hyperlipidemia (OR 2.32 p = 0.014), postoperative DM (OR 2.93, p<0.001), preoperative (OR 8.77, p<0.001) and postoperative (OR 2.64, p<0.001) eGFR <60mL/min/1.73m2 were significantly associated with de novo ED. CONCLUSIONS Patients undergoing RN had significantly higher de novo ED compared to a contemporary, well-matched cohort undergoing NSS. RN, DM, and eGFR<60 were associated with development of ED. Further investigation on effects of nephron loss on ED is requisite. © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e615-e616 Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Ryan Kopp San Diego, CA More articles by this author Jonathan Silberstein New York, NY More articles by this author Reza Mehrazin Memphis, TN More articles by this author Aditya Bagrodia Memphis, TN More articles by this author Robert Wake Memphis, TN More articles by this author Anthony Patterson Memphis, TN More articles by this author Jim Wan Memphis, TN More articles by this author Ithaar Derweesh San Diego, CA More articles by this author Expand All Advertisement Advertisement PDF DownloadLoading ...

Third Prize: The Role of Endoscopic Nephron-Sparing Surgery in the Management of Upper Tract Urothelial Carcinoma

Upper tract urothelial carcinoma (UT-UC) is an uncommon disease with pronounced difference in 5-year survival for noninvasive (96%) versus invasive (17%) disease. High survival rate of early disease questioned the accepted norm of using radical nephroureterectomy (RNU) for all stages. This review assesses effectiveness of endoscopic management for UT-UC. A review of 131 UT-UC patients seen between January 1999 and October 2009 was performed. Demographic, clinicopathologic, and outcomes data were collected and compared between patients initially managed with RNU versus those initially managed with nephron-sparing surgery (NSS). The chi-square or Fisher's exact tests for categorical variables and the Wilcoxon-Mann-Whitney test for continuous variables were used. Clinical and pathologic stages of RNU patients were evaluated with chi-square testing, whereas difference in length of stay was detected using linear regression. Recurrence rates were compared using multivariate Cox regression. The two arms had similar distributions of age, sex, frequency of medical comorbidities, American Society of Anesthesiologists (ASA), and Charlson scores. Mean-adjusted length of stay was 2.1 (95% confidence interval [1.6, 2.5]) and 5.5 days (95% confidence interval [5.3, 6.4]) for the NSS and RNU groups, respectively (p < 0.001). Comparison of clinical and pathologic stages of RNU patients showed a difference (p < 0.001), with under-staging noted in 32%. Men (Hazards Ratio = 2.9 [1.5-5.5], p = 0.001) and NSS patients (hazards ratio [HR] = 3.5 [1.7-7.3], p < 0.001) had threefold increased recurrence risk. NSS offered shorter hospital stay but had increased risk of recurrence. Therefore, extreme care should be made to rule out occult invasive tumors preoperatively. Patients being managed endoscopically must be informed of the necessity for close follow-up.

Oncologic Long-term Outcome of Elective Nephron-sparing Surgery Versus Radical Nephrectomy in Patients With Renal Cell Carcinoma Stage pT1b or Greater in a Matched-pair Cohort

To analyze the oncologic outcome and overall survival (OS) for patients with renal cell carcinoma (RCC) >4 cm undergoing radical nephrectomy (RN) or elective nephron-sparing surgery (NSS) in a matched-pair cohort. From 1988 to 2007, we identified 829 patients in our clinic treated with either RN (n = 641) or open NSS (n = 188) for renal masses >4 cm. After matching the cohort for age, time of surgery, grade, TNM stage, tumor size, and sex and excluding patients with metastases, benign lesions with an imperative indication, and those with missing records, 173 remained for oncologic analysis. OS, cancer-specific survival, and progression-free survival were estimated using the Kaplan-Meier method. The association with death was evaluated with Cox proportional hazards regression analysis. At the last follow-up visit, 39 patients had died of any cause and 134 were alive at a median of 7.0 years. RN and elective NSS had been performed in 100 and 73 patients, respectively. The OS (P = .357), progression-free survival (P = .558), and cancer-specific survival (P = .239) were not significantly different between the elective NSS and RN groups using the Kaplan-Meier method. On univariate and multivariate Cox regression analysis, the type of surgery did not have an effect on OS (hazard ratio 1.35, 95% confidence interval 0.71-2.54, P = .359). Our results suggest that it is oncologically safe to perform NSS for renal tumors >4 cm, for which the surgical feasibility according to the tumor location, rather than the tumor size, seemed to be the limiting factor.