Comparison of complications after radical and partial nephrectomy: results from the National Veterans Administration Surgical Quality Improvement Program

Perioperative outcomes following robot-assisted partial nephrectomy in elderly patients

OBJECTIVE

To compare perioperative outcomes following robot-assisted partial nephrectomy (RAPN) in patients with age ≥ 70 years to age < 70 years.

METHODS

Using Vattikuti Collective quality initiative (VCQI) database for RAPN we compared perioperative outcomes following RAPN between the two age groups. Primary outcome of the study was to compare trifecta outcomes between the two groups. Propensity matching using nearest neighbourhood method was performed with trifecta as primary outcome for sex, body mass index (BMI), solitary kidney, tumor size and Renal nephrometery score (RNS).

RESULTS

Group A (age ≥ 70 years) included 461 patients whereas group B included 1932 patients. Before matching the two groups were statistically different for RNS and solitary kidney rates. After propensity matching, the two groups were comparable for baselines characteristics such as BMI, tumor size, clinical symptoms, tumor side, face of tumor, solitary kidney and tumor complexity. Among the perioperative outcome parameters there was no difference between two groups for operative time, blood loss, intraoperative transfusion, intraoperative complications, need for radical nephrectomy, positive margins and trifecta rates. Warm ischemia time was significantly longer in the younger age group (18.1 min vs. 16.3 min, p = 0.003). Perioperative complications were significantly higher in the older age group (11.8% vs. 7.7%, p = 0.041). However, there was no difference between the two groups for major complications.

CONCLUSION

RAPN in well-selected elderly patients is associated with comparable trifecta outcomes with acceptable perioperative morbidity.

Acute kidney injury after nephrectomy: a new nomogram to predict postoperative renal function

Background

We aimed to develop a nomogram based on preprocedural features for early prediction of acute kidney injury (AKI) and to assess the prognosis in patients after radical and partial nephrectomy.

Methods

The study included a development cohort of 1111 patients who were treated between June 2012 and June 2017 and an additional validation cohort of 356 patients who were treated between July 2017 and June 2018. Stepwise regression and logistic regression analyses were used to evaluate the association between predictors and AKI. Incorporating all independent predictors, a nomogram for postoperative AKI was developed and externally validated. Patients were followed up for 5 years to assess renal function, acute kidney disease (AKD), chronic kidney disease (CKD), hospital readmission and mortality were key prognosis we focused on.

Results

After multivariate logistic regression, radical nephrectomy (odds ratio (OR) = 3.57, p < 0.001), aspirin (OR = 1.79, p = 0.008), systolic blood pressure (OR = 1.41, p = 0.004), triglyceride (OR = 1.26, p = 0.024), and alkaline phosphatase (OR = 1.75, p = 0.034) were independent risk factors for postoperative AKI, while albumin (OR = 0.72, p = 0.031) was a protective factor for postoperative AKI. Patients with a higher estimated glomerular filtration rate (eGFR) (60–90 ml/min/1.73 m², OR = 0.41, p = 0.004; ≥ 90 ml/min/1.73 m², OR = 0.37, p < 0.001) were less prone to AKI than those with a lower eGFR (< 15 ml/min/1.73 m²). These predictors were all included in the final nomogram. The area under the receiver operating characteristics curve for the model were 0.77 (p < 0.001) in the development cohort and 0.72 (p < 0.001) in the validation cohort. The incidence of AKD and CKD were 27.12 and 18.64% in AKI group, which were much higher than those in no AKI group (p < 0.001).

Conclusions

The nomogram had excellent predictive ability and might have significant clinical implications for the early detection of AKI in patients undergoing nephrectomy.

Incident CKD after Radical or Partial Nephrectomy

The comparative effectiveness of partial nephrectomy versus radical nephrectomy to preserve kidney function has not been well established. We determined the risk of clinically significant (stage 4 and higher) CKD after radical or partial nephrectomy among veterans treated for kidney cancer in the Veterans Health Administration (2001-2013). Among patients with preoperative eGFR≥30 ml/min per 1.73 m2, the incidence of CKD stage 4 or higher after radical (n=9759) or partial nephrectomy (n=4370) was 7.9% overall. The median time to stage 4 or higher CKD after surgery was 5 months, after which few patients progressed. In propensity score-matched cohorts, partial nephrectomy associated with a significantly lower relative risk of incident CKD stage 4 or higher (hazard ratio, 0.34; 95% confidence interval [95% CI], 0.26 to 0.43, versus radical nephrectomy). In a parallel analysis of patients with normal or near-normal preoperative kidney function (eGFR≥60 ml/min per 1.73 m2), partial nephrectomy was also associated with a significantly lower relative risk of incident CKD stage 3b or higher (hazard ratio, 0.15; 95% CI, 0.11 to 0.19, versus radical nephrectomy) in propensity score-matched cohorts. Competing risk regression models produced consistent results. Finally, patients treated with a partial nephrectomy had reduced risk of mortality (hazard ratio, 0.55; 95% CI, 0.49 to 0.62). In conclusion, compared with radical nephrectomy, partial nephrectomy was associated with a marked reduction in the incidence of clinically significant CKD and with enhanced survival. Postoperative decline in kidney function occurred mainly in the first year after surgery and appeared stable over time.

Influence of hospital volume on nephrectomy mortality and complications: a systematic review and meta-analysis stratified by surgical type

OBJECTIVES

The provision of complex surgery is increasingly centralised to high-volume (HV) specialist hospitals. Evidence to support nephrectomy centralisation however has been inconsistent. We conducted a systematic review and meta-analysis to determine the association between hospital case volumes and perioperative outcomes in radical nephrectomy, partial nephrectomy and nephrectomy with venous thrombectomy.

METHODS

Medline, Embase and the Cochrane Library were searched for relevant studies published between 1990 and 2016. Pooled effect estimates for nephrectomy mortality and complications were calculated for each nephrectomy type using the DerSimonian and Laird random-effects model. Sensitivity analyses were performed to examine the effects of heterogeneity on the pooled effect estimates by excluding studies with the heaviest weighting, lowest methodological score and most likely to introduce bias from misclassification of standardised hospital volume.

RESULTS

Some 226 372 patients from 16 publications were included in our review and meta-analysis. Considerable between-study heterogeneity was noted and only a few reported volume-outcome relationships specifically in partial nephrectomy or nephrectomy with venous thrombectomy.HV hospitals were correlated with a 26% and 52% reduction in mortality for radical nephrectomy (OR 0.74, 95% CI 0.61 to 0.90, p<0.01) and nephrectomy with venous thrombectomy (OR 0.48, 95% CI 0.29 to 0.81, p<0.01), respectively. In addition, radical nephrectomy in HV hospitals was associated with an 18% reduction in complications (OR 0.82, 95% CI 0.73 to 0.92, p<0.01). No significant volume-outcome relationship in mortality (OR 0.84, 95% CI 0.31 to 2.26, p=0.73) or complications (OR 0.85, 95% CI 0.55 to 1.30, p=0.44) was observed for partial nephrectomy.

CONCLUSIONS

Our findings suggest that patients undergoing radical nephrectomy have improved outcomes when treated by HV hospitals. Evidence of this in partial nephrectomy and nephrectomy with venous thrombectomy is however not yet clear and could be secondary to the low number of studies included and the small patient number in our analyses. Further investigation is warranted to establish the full potential of nephrectomy centralisation particularly as existing evidence is of low quality with significant heterogeneity.

Impact of Perioperative Infection on Cancer Specific Survival after Nephrectomy for Renal Cell Carcinoma

PURPOSE

Several case reports have documented rare spontaneous cancer regression following systemic infections. Immune related targeted therapies are now available for many cancers, including renal cell carcinoma. We hypothesized that perioperative infection after nephrectomy for renal cell carcinoma may impact long-term cancer specific survival.

MATERIALS AND METHODS

We performed a retrospective cohort study using SEER (Surveillance, Epidemiology and End Results)-Medicare claims data from 2004 to 2011. ICD-9 and CPT codes were used to identify patients older than 65 years who underwent radical or partial nephrectomy for renal cell carcinoma. Patients hospitalized for infection within 30 days of surgery were identified. Study exclusion criteria included death within 90 days of surgery, immunodeficiency and metastatic disease at diagnosis. Kaplan-Meier curves were used to evaluate cancer specific survival between infection vs no infection groups. A Cox proportional hazards model was created to assess survival while controlling for age, gender, race, Elixhauser index, tumor grade, tumor size, histological subtype, AJCC (American Joint Committee on Cancer) stage, systemic therapy and geographic region.

RESULTS

Of 8,967 patients 493 (5.5%) were hospitalized for infection after nephrectomy. Median age was 74 years (IQR 69-79), the mean ± SD Elixhauser index was 4.9 ± 7.4 and median followup was 42 months (IQR 22-67). Following nephrectomy univariable Cox regression showed a nonsignificant improvement in cancer specific survival in patients with a serious infection requiring hospitalization (HR 0.84, 95% CI 0.69-1.00, p = 0.054). Cox multivariable regression revealed significant improvement in cancer specific survival for the same population (HR 0.75, 95% CI 0.57-0.99, p = 0.04). This effect was primarily due to patients with larger (7 cm or greater) tumors (HR 0.67, 95% CI 0.44-0.99, p = 0.049). No impact was observed among patients with smaller (less than 7 cm) tumors (HR 0.82, 95% CI 0.57-1.19, p = 0.3).

CONCLUSIONS

In patients with T2 (7 cm or greater) renal cell carcinoma who undergo nephrectomy perioperative infection may improve cancer specific survival.

Brief communication (Original). Predictive factors for postoperative complications in radical nephrectomy for renal cell carcinoma

Background: Radical nephrectomy is the treatment of choice for large renal cell carcinoma (RCC).

Objectives: To describe the complications after radical nephrectomy for suspected or proven RCC and analyze the risk factors.

Materials and methods: We retrospectively reviewed medical records from 110 patients who underwent radical nephrectomy for RCC in our institution between January 2007 and December 2013. The clinicopathological data of all patients were recorded and complications were graded using modified Clavien classification. Univariate and multivariate analysis was made of the predictive factors for complications.

Results: Fifty postoperative complications occurred in 34 patients (31%) within 30 days, including 11% transfusion related complications. There were 22% minor complications (6% grade 1, 16% grade 2) and 9% major complication (5% grade 3, 2% grade 4, and 2% grade 5). The most common complications were transfusion-related, re-laparotomy because of bleeding, and prolong ileus. In univariate analysis, pathological T-stage (P = 0.001), American Society of Anesthesiologists (ASA) score (P = 0.007), tumor size (P = 0.01), and tumor diameter >4 cm (P = 0.03) were significant predicting factors. Major Charlson comorbidity index (CCI >2) was the only significant factor for major complications (P = 0.04). In multivariate analysis, ASA score was a significant independent predictor for overall complications (odds ratio 4.83, P = 0.01).

Conclusions: ASA score was a significant predictive factor for overall postoperative complications. Comorbidities was also a predictor for major complications in radical nephrectomy. Preoperative risk stratification for complications should be considered during decision-making and for proper counseling of patients.

Partial nephrectomy vs. radical nephrectomy for renal tumors: A meta-analysis of renal function and cardiovascular outcomes

OBJECTIVES

The widespread use of partial nephrectomy (PN) has led to the preservation of functional renal parenchyma. However, the benefits of PN on renal function and cardiovascular outcomes remain controversial. Thus, a meta-analysis was performed to reconcile the conflicting results.

MATERIALS AND METHODS

PubMed, Embase, and the Cochrane Library were searched from inception to August 2015, and databases with all relevant comparative studies were included. The Mantel-Haenszel method with random-effects models was used to determine the pooled hazard ratios (HRs) for each outcome.

RESULTS

In total, 26 studies were pooled for new-onset chronic kidney disease, and 6 studies were pooled for cardiovascular outcomes. According to the pooled estimates, PN correlated with a 73% risk reduction of new-onset chronic kidney disease in all included patients (HR = 0.27, P<0.0001) and a 65% risk reduction in patients with tumors>4cm (HR = 0.35, P<0.0001) compared with radical nephrectomy. There were no significant differences between groups regarding postsurgery cardiovascular events (HR = 0.86, P = 0.238) and cardiovascular death (HR = 0.79, P = 0.196). Despite inherent selection biases, the pooled estimates were robust in sensitivity and subgroup analyses.

CONCLUSIONS

Our findings suggest that PN lowers the postoperative risk of new-onset chronic kidney disease. Nevertheless, the protection of renal function by PN did not reduce the risk of cardiovascular outcomes. However, this result remains controversial, and additional large-scale evaluations are warranted.

Contemporary Use of Partial Nephrectomy: Are Older Patients With Impaired Kidney Function Being Left Behind?

OBJECTIVE

To assess whether patient factors, such as age and preoperative kidney function, were associated with receipt of partial nephrectomy in a national integrated healthcare system.

MATERIALS AND METHODS

We identified patients treated with a radical or partial nephrectomy from 2002 to 2014 in the Veterans Health Administration. We examined associations among patient age, sex, race or ethnicity, multimorbidity, baseline kidney function, tumor characteristics, and receipt of partial nephrectomy. We estimated the odds of receiving a partial nephrectomy and assessed interactions between covariates and the year of surgery to explore whether patient factors associated with partial nephrectomy changed over time.

RESULTS

In our cohort of 14,186 patients, 4508 (31.2%) received a partial nephrectomy. Use of partial nephrectomy increased from 17% in 2002 to 32% in 2008 and to 38% in 2014. Patient race or ethnicity, age, tumor stage, and year of surgery were independently associated with receipt of partial nephrectomy. Black veterans had significantly increased odds of receipt of partial nephrectomy, whereas older patients had significantly reduced odds. Partial nephrectomy utilization increased for all groups over time, but older patients and patients with worse baseline kidney function showed the least increase in odds of partial nephrectomy.

CONCLUSION

Although the utilization of partial nephrectomy increased for all groups, the greatest increase occurred in the youngest patients and those with the highest baseline kidney function. These trends warrant further investigation to ensure that patients at the highest risk of impaired kidney function are considered for partial nephrectomy whenever possible.

Renal artery pseudoaneurysm after robotic-assisted partial nephrectomy: case report

Renal artery pseudoaneurysm is an uncommonly recognized complication following partial nephrectomy. It is more common with trauma and percutaneous renal intervention. Furthermore, it is rarely reported with minimally invasive laparoscopic partial nephrectomy. Herein, we report the first case to our knowledge of renal artery pseudoaneurysm following a robotic-assisted partial nephrectomy.

Surveillance of Small Renal Masses

The widespread utilization of imaging has led to an increasing incidence of small renal masses (SRMs). However, at least 20% are benign. Nevertheless, nephron-sparing surgery is the standard treatment for SRMs without pretreatment characterization with biopsy. Elderly patients and patients with multiple comorbidities and limited life expectancy may safely be managed with active surveillance with low risk of disease progression and mortality. An initial period of observation to determine tumor growth kinetics is safe and appropriate in select candidates. Renal tumor biopsy is accurate, safe and should be considered for SRMs prior to finalizing treatment plans.

Incidence and risk factors for 30-day readmission in patients undergoing nephrectomy procedures: a contemporary analysis of 5276 cases from the National Surgical Quality Improvement Program database

OBJECTIVE

To explore factors associated with readmission after nephrectomy procedures using a large national database.

MATERIALS AND METHODS

A national surgical outcomes database, the American College of Surgeon-National Surgical Quality Improvement Program registry, was queried for data on all patients undergoing open partial nephrectomy (OPN), minimally invasive (laparoscopic + robotic) partial nephrectomy (MIPN), and minimally invasive radical nephrectomy (MIRN) in 2011 and 2012. Patients undergoing these procedures were identified using the Current Procedural Terminology codes. The primary outcome was unplanned 30-day hospital readmission. A multivariate logistic regression model was constructed to assess for factors independently associated with the primary outcome.

RESULTS

Overall, 5276 cases were identified and included in the analysis: 1411 OPN (26.7%), 2210 MIPN (41.8%), and 1655 MIRN (31.3%). Overall, the 30-day readmission rate was 5.9% (7.8% for OPN, 4.5% for MIPN, and 6.1% for MIRN). On multivariate analysis, the odds for 30-day readmission for MIPN was approximately 70% that of OPN (P = .012). The odds for 30-day readmission for 2012 was about 80% of that of 2011 (P <.001). History of steroid use and of bleeding disorder and occurrence of postoperative transfusion increase the odds of readmission by approximately 2 (P = .005, P = .038, and P <.001, respectively). A postoperative urinary infection increased the odds of readmission by 5.5 (P <.001).

CONCLUSION

Contemporary 30-day readmission rates after nephrectomy procedures are influenced by specific patients' characteristics as well as postoperative adverse events. Moreover, contemporary MIPN seems to carry lower odds of readmission than OPN. It remains to be determined to what extent these findings are influenced by the expanding role of robotic technology.

Renal surgery for kidney cancer in Germany 2005-2006: length of stay, risk of postoperative complications and in-hospital death

Background

Representative statistics of surgical care among patients with kidney cancer are scant. With the introduction of the diagnosis related group system in Germany, it is now possible to provide nationwide statistics on surgical care. We studied in-hospital mortality risk in relation to comorbidity and complications, length of hospital stay in relation to surgical approach and comorbidity, and risk of complications in relation to surgical approach among kidney cancer patients undergoing nephrectomy.

Methods

We analyzed the nationwide hospitalization file of the years 2005 and 2006 including 23,753 hospitalizations with a diagnosis of renal cancer and partial or complete nephrectomy and classified comorbidity (Charlson comorbidity index) and complications. Length of stay, risk of in-hospital complications and in-hospital death were analyzed by linear regression and log-linear regression (relative risks (RR) and 95% confidence intervals (95% CI)).

Results

The overall in-hospital mortality was 1.4%. Per one unit increase of the Charlson comorbidity index, the adjusted risk of in-hospital mortality increased by 53% (95% CI 47-59%). The risks of bleeding or acute posthaemorrhagic anemia, respiratory, urological and gastrointestinal complications and infections ranged between 1.1% and 2.7% with the exception of bleeding or acute posthaemorrhagic anemia with 18.4%. Complications were associated with an increased adjusted in-hospital mortality risk. Highest adjusted mortality risk ratios were observed for gastrointestinal (RR = 3.61, 95% CI 2.32-5.63) and urological complications (RR = 3.62, 95% CI 2.62-5.00). The risk of haemorrhage or acute posthaemorrhagic anemia was lower for total laparoscopic nephrectomies than total open nephrectomies. The adjusted risk of gastrointestinal complications was lower for partial open compared to total open nephrectomy (adjusted RR = 0.66, 95% CI 0.45-0.97). Total laparoscopic nephrectomy was associated with shorter length of stay (−3.3 days; 95% CI 2.9-3.7 days) compared to total open nephrectomy. The estimated age-adjusted increase of length of stay per one unit increase of the Charlson comorbidity index was 1.3 days (95% CI 1.2-1.4 days).

Conclusions

In this representative population-based analysis, we found that the surgical approach is associated with the risk of complications and length of hospital stay. Furthermore, in the era of ageing populations, renal cancer patients with comorbidities should be counseled about their increased in-hospital mortality risk.

A generation of laparoscopic nephrectomy: stage-specific surgical and oncologic outcomes for laparoscopic nephrectomy in a single center

PURPOSE

To determine the stage-specific operative, postoperative and oncologic outcomes, for patients undergoing a laparoscopic radical nephrectomy (LRN) for renal cell carcinoma (RCC) in a single center and assess changes over a generation of practice.

PATIENTS AND METHODS

From December 1992 to July 2011, data were collected prospectively for 854 consecutive simple laparoscopic necphrectomies (LNs) and LRNs, 397 of which were LRNs for RCC. The first LRN was performed in December 1997. Stage-specific surgical and oncologic outcomes were assessed across the study period. Patients were then grouped into three equal consecutive cohorts. Case mix and surgical outcomes were compared to assess changes with departmental experience.

RESULTS

There were 206, 71, 118, and 2 patients across stages pT1, pT2, pT3, and pT4, respectively. Median operative time was significantly shorter for pT1 tumors (125, 150 and 150 min for pT1-3, P<0.021), while median estimated blood loss (EBL) was greater for pT3 tumors (50, 50, 100 mL, for pT1-3, P<0.001). Median follow-up time was 31, 30, and 18 months, respectively, across pT1-pT3. There was a significant difference in 5-year overall survival (82.4%, 68.4%, 58.9%), cancer-specific survival (99.5%, 83.6%, 66.5%) and progression free survival (86.5%, 66.3%, 47.5%) across these stage-specific subgroups. Over the three cohorts, there was an increase in LRN performed for locally advanced disease and cytoreduction. With greater surgical experience, there was improvement in median operative time and median EBL in localized disease over the three periods, but no significant changes for locally advanced disease.

CONCLUSION

This is the largest reported series of LRN in the United Kingdom. Departmental experience has resulted in improved surgical outcomes for localized RCC, with expansion of practice in more complex advanced disease. Laparoscopic nephrectomy is both operatively and oncologically safe in T1 and T2 disease, and although technically more demanding, it is also safe in selected T3 disease.

The type of nephrectomy has little effect on overall survival or cardiac events in patients of 70 years and older with localized clinical t1 stage renal masses

Purpose

To compare the outcomes of nephron-sparing options (e.g., partial nephrectomy [PN]) and low-surgical-morbidity options (e.g., radical nephrectomy [RN]) in elderly patients with limited life expectancy.

Materials and Methods

We retrospectively reviewed 135 patients aged 70 years or older who underwent RN (n=82) or PN (n=53) for clinical T1 stage renal masses between January 2000 and December 2012. Clinicopathologic data were thoroughly analyzed and compared between the RN and PN groups. The modification of diet in renal disease equation was used to estimate glomerular filtration. Overall survival and cardiac events were assessed by using Kaplan-Meier survival analysis and Cox proportional-hazards regression modeling.

Results

Over a median follow-up period of 59.72 months, 17 patients (20.7%) in the RN group and 3 patients (5.7%) in the PN group died. Chronic kidney disease (<60 mL/min/1.73 m²) developed more frequently in RN patients than in PN patients (75.6% vs. 41.5%, p<0.001). The 5-year overall survival rate did not differ significantly between the RN and PN groups (90.7% vs. 93.8%; p=0.158). According to the multivariate analysis, the Charlson comorbidity index score was an independent predictor of overall survival (hazard ratio [HR], 2.679, p=0.037). Type of nephrectomy was not significantly associated with overall survival (HR, 2.447; p=0.167) or cardiac events (HR, 1.147; p=0.718).

Conclusions

Although chronic kidney disease was lower after PN, overall survival and cardiac events were similar regardless of type of nephrectomy.

Assessing the burden of complications after surgery for clinically localized kidney cancer by age and comorbidity status

OBJECTIVE

To examine the association between high-risk patient status (age >75 years or Charlson comorbidity index count >2) and postoperative complications in patients undergoing surgical management for clinically localized renal tumors.

MATERIALS AND METHODS

Patients undergoing radical nephrectomy (RN) or partial nephrectomy (PN) (2005-2012) for localized renal cell carcinoma were analyzed. Multivariate logistic regressions were used to test the association between high-risk status and postoperative complications adjusting for patient, tumor, and operative characteristics.

RESULTS

Of 1092 patients undergoing PN (71.9%) or RN (28.1%) for clinically localized renal tumors, 255 (23.4%) were classified as high risk, and 175 patients (16%) developed at least 1 complication (mean 1.6 ± 1.0). Of note, 22.4% and 14.1% of high- and low-risk patients developed a complication, respectively (P = .002). Comparing high- and low-risk patients, significant differences in Clavien I-II (20.4% vs 11.1%; P <.001) and medical (16.1% vs 8.1%, P <.001) complications were observed, whereas no differences were seen in Clavien III-V or surgical complications. No differences in complications were observed comparing patients treated with RN and PN, albeit high-risk patients were more likely to undergo RN (35.3% vs 25.9%, P = .04). After adjustment, the odds of incurring any complication were 1.9 times higher in high- compared with low-risk patients (odds ratio 1.9 [confidence interval 1.3-2.8]).

CONCLUSION

Regardless of surgical type, patients deemed high risk by age and comorbidity criteria were more likely to incur a postoperative complication after renal mass resection. Improved understanding of surgical risks in the elderly and infirmed will help better inform patients deciding between active surveillance and resection of renal tumors.

[Nephrectomy: complication management]

BACKGROUND

Nephrectomy is a standard procedure that is associated with a low complication rate.

OBJECTIVES

Based on an analysis of the literature, expert recommendations, and our own experience, the management of complications during and after nephrectomy is described.

RESULTS

Complications during and after nephrectomy can be avoided by careful surgical planning, optimal approach and exposure, and precise knowledge of the principles of anatomy. The treatment of bleeding complications and injuries to neighboring structures are essential elements in the management of complications. Hernia and relaxation of the lumbar muscles should be avoided.

CONCLUSION

Morbidity associated with nephrectomy can be reduced by careful surgical planning and paying attention to the basic anatomical and surgical principles.

Pilot study comparing the two hemostatic agents in patients undergoing partial nephrectomy

Background

Recently studies have demonstrated improved outcomes in patients undergoing nephron-sparing surgery (NSS) for low stage renal tumors, thus NSS is widely accepted as the treatment option for these patients. With NSS, there is a risk of renal hemorrhage and thus haemostatic agents may be routinely applied to the cut surface of the kidney. Herein we compare two commercially available haemostatic agents applied intra-operatively to the cut surface of the kidney. Post-operative outcomes (oncologic and non-oncologic) are reported.

Methods

The medical records of 23 patients with suspicious renal mass documented on axial imaging and who underwent open NSS via a mini-subcostal incision were extensively reviewed. One of two haemostatic agents (Floseal^®, n = 11; Arista^®, n = 12) was intra-operatively applied to the cut surface of the kidney. Chi-square and T- student test was used to compare outcomes between the cohort of 11 patients who had Floseal^® and the 12 patients who had Arista^®.

Results

Median pre-operative size of renal mass was 4.3 cm (range 1.5-7.0 cm). Final pathology revealed 3 oncocytomas and 20 renal cell carcinoma (17 clear cell, 1 chromophobe and 2 papillary), pT1a = 14 and pT1b = 6. Mean intra-operative blood loss and hospital stay between the Floseal^®vs. Arista^® cohorts did not significantly differ (227 mL vs. 250 mL, p = 0.68 and 4.4 days vs. 4.5 days, p = 0.76, respectively). Intra-operative and post-operative complications were not different between the two cohorts. No recurrences have been documented with a mean follow-up of 18 months.

Conclusion

Along with meticulous surgical technique, the use of either haemostatic agent (Floseal^® or Arista^®) was not associated with high rate of intra-operative or post-operative haemorrhage. Thus either haemostatic agent may be successfully used during NSS.

Trends and variations in utilization of nephron-sparing procedures for stage I kidney cancer in the United States

PURPOSE

The incidental detection of early-stage kidney tumors is increasing in the United States. Nephron-sparing approaches (NS) to managing these tumors are equivalent to radical nephrectomy (RN) in oncologic outcomes and have a decreased impact on renal function. Our objective was to evaluate trends in the use of NS over the past decade and the socioeconomic factors associated with its use.

METHODS

The National Cancer Database was queried to identify patients with stage I kidney cancer between 2000 and 2008. Patients were classified by the type of surgery as NS (local destruction and local excision) or RN. Patients were further categorized by age, race, insurance status, and income. Log-binomial regression was used to estimate prevalence ratios (PR) for the proportion of NS to RN according to demographic and socioeconomic characteristics.

RESULTS

From 2000 to 2008, there were 142,194 cases of kidney cancer reported to the NCDB. In these cases, 43,034 (30.3 %) patients had NS, and 86,431 (60.78 %) patients had RN. The prevalence of NS increased 10 % per year (PR = 1.10, p < 0.0001)-from 20.0 % in 2000 to 45.1 % in 2008. Older age, lower income, Black race, Hispanic ethnicity, and lack of health insurance were associated with a decreased prevalence of NS.

CONCLUSIONS

NS as a treatment for stage I kidney cancer has increased steadily since 2000. Age, racial, and socioeconomic differences may exist in the utilization of NS. Additional analyses, with patient level data, are required to address the independent significance of these variables in an effort to develop strategies to mitigate these potential disparities.

Comparative effectiveness for survival and renal function of partial and radical nephrectomy for localized renal tumors: a systematic review and meta-analysis

PURPOSE

The relative effectiveness of partial vs radical nephrectomy remains unclear in light of the recent phase 3 European Organization for the Research and Treatment of Cancer trial. We performed a systematic review and meta-analysis of partial vs radical nephrectomy for localized renal tumors, considering all cause and cancer specific mortality, and severe chronic kidney disease.

MATERIALS AND METHODS

Cochrane Central Register of Controlled Trials, MEDLINE®, EMBASE®, Scopus and Web of Science® were searched for sporadic renal tumors that were surgically treated with partial or radical nephrectomy. Generic inverse variance with fixed effects models were used to determine the pooled HR for each outcome.

RESULTS

Data from 21, 21 and 9 studies were pooled for all cause and cancer specific mortality, and severe chronic kidney disease, respectively. Overall 31,729 (77%) and 9,281 patients (23%) underwent radical and partial nephrectomy, respectively. According to pooled estimates partial nephrectomy correlated with a 19% risk reduction in all cause mortality (HR 0.81, p < 0.0001), a 29% risk reduction in cancer specific mortality (HR 0.71, p = 0.0002) and a 61% risk reduction in severe chronic kidney disease (HR 0.39, p < 0.0001). However, the pooled estimate of cancer specific mortality for partial nephrectomy was limited by the lack of robustness in consistent findings on sensitivity and subgroup analyses.

CONCLUSIONS

Our findings suggest that partial nephrectomy confers a survival advantage and a lower risk of severe chronic kidney disease after surgery for localized renal tumors. However, the results should be evaluated in the context of the low quality of the existing evidence and the significant heterogeneity across studies. Future research should use higher quality evidence to clearly demonstrate that partial nephrectomy confers superior survival and renal function.

Does partial nephrectomy at an academic institution result in better outcomes?

PURPOSE

Partial nephrectomy (PN) outcomes may be better at academic institutions than at non-academic centers. Peer-review, sub-specialized practice profile, higher individual surgeon and institutional caseload may explain this observation. To the best of our knowledge, the role of institutional academic affiliation has not been examined with regard to PN postoperative outcomes.

METHODS

Within the Health Care Utilization Project Nationwide Inpatient Sample (NIS), we focused on PNs performed within the 10 most contemporary years (1998-2007). We explored the effect of academic status on three short-term PN outcomes (intraoperative and postoperative complications, as well as in-hospital mortality). Multivariable logistic regression analyses further adjusted for age, race, gender, Charlson Comorbidity Index (CCI), surgical approach, hospital region, annual hospital caseload and insurance status.

RESULTS

Overall, 8,513 PNs were identified. Of those, 5,906 (69.4%) were recorded at academic institutions. Academic institution patients had lower CCI, were less frequently Caucasian and more frequently had private insurance (all P < 0.001). Academic institution PNs were associated with fewer postoperative complications (14.6% vs. 16.6%, P = 0.018). In multivariable analyses, institutional academic status did not affect the three short-term PN outcomes.

CONCLUSIONS

Patient selection explains better PN postoperative outcomes at academic institutions. Control for these biases removes the outcome differences, at least when the three short-term PN outcomes are considered. However, the interpretation of these findings needs to take into account the lack of adjustment for case complexity.

The effect of insurance status on outcomes after partial nephrectomy

BACKGROUND

Privately insured patients may have favorable health outcomes when compared to those covered by federally funded initiatives. This study explored the effect of insurance status on five short-term outcomes after partial nephrectomy (PN).

METHODS

Within the Health Care Utilization Project Nationwide Inpatient Sample (NIS), we focused on PNs performed between 1998 and 2007. We tested the rates of in-hospital mortality, blood transfusions, prolonged length of stay, as well as intraoperative and postoperative complications, stratified according to insurance status. Multivariable logistic regression analyses fitted with general estimation equations for clustering among hospitals further adjusted for confounding factors.

RESULTS

Overall, 8,513 PNs were identified. Of those, most patients were privately insured (53.5%), followed by Medicare (37.5%), uninsured (4.6%) and Medicaid (4.4%). Medicare and Medicaid patients had higher rates of transfusions (P < 0.001) and overall postoperative complications (P < 0.001). In multivariable analyses, when compared to privately insured patients, Medicaid patients had higher rates of transfusions (OR = 1.91, P < 0.001) and prolonged length of stay (OR = 1.49, P < 0.001). Medicare patients had higher rates of overall postoperative complications (OR = 1.24, P = 0.015) and length of stay beyond the median (OR = 1.4, P < 0.001).

CONCLUSION

Patients with private insurance undergoing PN have better short-term outcomes, when compared to their publicly insured counterparts.

The effect of age on the morbidity of kidney surgery

PURPOSE

Previous reports of the morbidity of renal surgery have been primarily from academic tertiary referral centers and, thus, they may not reflect general clinical practice. We determined the effect of age and comorbidity on in-hospital surgical morbidity for radical and partial nephrectomy on a population level.

MATERIALS AND METHODS

Data were obtained from a Canadian national discharge abstract database. From April 1998 to March 2008 information was available on 20,286 radical and 4,292 partial nephrectomies. Complications were identified using specific ICD-9 and 10 diagnosis and procedure codes. Complication rates were estimated by procedure type and by various explanatory variables, including patient age and Charlson comorbidity score. Multivariate logistic regressions were constructed for radical and partial nephrectomy to determine associations between explanatory variables and complications.

RESULTS

Overall complications developed in 34.1% of radical and 34.3% of partial nephrectomy cases. Patients were more likely to have cardiac, respiratory, vascular and surgical complications after radical nephrectomy while they were more likely to experience genitourinary and nephrectomy specific complications after partial nephrectomy. On multivariate logistic regression after radical and partial nephrectomy complications increased with age and Charlson score. After adjusting for other covariates patients with a Charlson score of greater than 2 were approximately 6 times more likely to experience a complication than patients with a Charlson score of 0 for radical and partial nephrectomy (OR 6.22, 95% CI 5.18-7.48 and OR 5.68, 95% CI 3.72-8.66, respectively).

CONCLUSIONS

In our population based study radical nephrectomy and partial nephrectomy were associated with higher morbidity than previously reported, particularly in the elderly population and in patients with comorbidity.

A new technique--"lipocorticoplasty"--for the closure of partial nephrectomy defects and its comparison with the standard technique

OBJECTIVE

We describe a new technique that can easily be used as a tension-free practical alternative in closing the renal defects resulting after open partial nephrectomy (PN).

METHODS

A new technique (called "lipocorticoplasty") where "wrapped fatty tissue" was placed in the tumor crater to close the renal defects that occur following PN is reported in 10 consecutive patients who underwent PN between May 2006 and January 2009 (Group I). Patients were compared with equal number of consecutive patients who underwent standard open PN before January 2009 (Group II) in terms of operative time, bleeding, tumor size, drain removal time, postoperative length of stay (PLOS), complications, and functional and oncological follow-up. Postoperative follow-up included physical examination, laboratory tests, and radiological screening at 3-month intervals for the first year, at 6-month intervals for the second year, and annually thereafter.

RESULTS

Mean tumor size (35.2 vs. 33.8 mm), operative time (156 vs. 165 min), bleeding (650 vs. 765 cc), drain removal time (2.8 vs. 2.5 POD), and PLOS (4.4 vs. 4.2 POD) were not statistically different between Group I and Group II, respectively. No intraoperative complications occurred. Postoperatively, transient complications without any permanent sequela were observed in 3 (1 in Group I and 2 in Group II) patients. Mean follow-up time was 16.1 months (7-26) in Group I and 19.1 months (8-36) in Group II. None of the patients had local or systemic recurrence at follow-up.

CONCLUSION

Our new technique provides obvious benefits in local hemostasis, simplifies parenchymal suturing, obviates the need for coaptation of the edges of the tumor bed defect under tension, and minimizes nephron loss due to kinking and tearing of renal parenchyma in the closure of the renal defects following open renal tumor excision.

Mini-Margin nephron sparing surgery for renal cell carcinoma 4 cm or less

Objectives. To explore the safety and efficacy of mini-margin nephron sparing surgery (NSS) for renal cell carcinoma (RCC) 4 cm or less. Methods. Total of 389 cases of RCC 4 cm or less with normal contralateral kidneys were included in the study, including 135 cases treated by mini-margin NSS, 98 by 1 cm-NSS and 156 by radical nephrectomy (RN). The clinical results were followed-up and comparatively analyzed. Results. The mean and median margin width for mm-NSS was 2.2 and 2.0 mm (range 0 to 5). Of them, 112 (83.0%) cases had margins of 3 mm or less, and 26 had margins of 0 mm (19.3%). The mean width of margin for 1 cm-NSS was 11.6 mm (median 12, range 10~15). None of the NSS patients had positive surgical margins. The mean follow-up for mm-NSS, 1 cm-NSS and RN patients was 69, 82 and 82 months, respectively. Three mm-NSS patients, two 1 cm- NSS and four RN patients died of non-cancer related causes. Two mm-NSS patient (1.6%) experienced local recurrence. No distant metastasis was detected in all the patients. The over all 5-year survivals for NSS and RN patients were 100%, 100% and 98.7%, respectively (P = .950). Conclusions. Mini-margin NSS is as safe and effective as 1 cm-NSS and RN in treating early localized RCC 4 cm or less.

Troubling outcomes from population-level analysis of surgery for upper tract urothelial carcinoma

OBJECTIVES

To review the surgical management of upper tract urothelial carcinoma (UTUC) on a population level. UTUC accounts for 5% of urothelial malignancies, making it less amenable to single-center reporting. Complete nephroureterectomy is the standard of care, and increasing evidence has shown that a suboptimal surgical technique is associated with an adverse prognosis.

METHODS

We obtained information for all patients diagnosed with UTUC (n = 830) and those treated surgically (n = 680) in the province of Ontario, Canada from the Ontario Cancer Registry from 1995 to 2004. Demographic, treatment, and vital status information was obtained for all patients, and pathology reports were available for 422 patients. The primary outcome was overall survival. The secondary outcomes included measures of surgical quality (ie, number of lymph nodes sampled, ureteral length excised, surgical margin status, and 30-day mortality) and disease-specific survival.

RESULTS

The unadjusted 5-year overall survival rate was 57.2%, with a median survival of 72.5 months. For those treated surgically, the 30-day mortality rate was 1.8%, and the positive surgical margin rate was 8.5%. Lymph nodes were identified in only 27% of the specimens, with a median yield of 1 (range 1-15). An estimated 25.8% of patients might have undergone incomplete ureteral resection at the time of nephroureterectomy.

CONCLUSIONS

UTUC is a lethal malignancy, with nearly one half the patients dying within 5 years. Furthermore, lymphadenectomy was rarely performed and approximately one fourth of patients might have undergone incomplete ureterectomy. The published outcomes from "centers of excellence" do not appear to reflect the surgical quality seen on a population level for this rare, but significant, malignancy.

Complications after radical and partial nephrectomy as a function of age

PURPOSE

Partial nephrectomy may be underused compared with radical nephrectomy in elderly patients due to concerns about higher complication rates. We determined if the association of age and perioperative outcomes differed between nephrectomy types.

MATERIALS AND METHODS

We identified patients who underwent radical or partial nephrectomy between January 2000 and October 2008. Using multivariable methods we determined whether the relationship between age and risk of postoperative complications, estimated blood loss or operative time differed by nephrectomy type.

RESULTS

Of 1,712 patients 651 (38%) underwent radical nephrectomy and 1,061 (62%) underwent partial nephrectomy. Patients treated with partial nephrectomy had higher complication rates than those who underwent radical nephrectomy (20% vs 14%). In a multivariable model age was significantly associated with a small increase in risk of complications (OR for 10-year age increase 1.17, 95% CI 1.04-1.32, p = 0.009). When including an interaction term between age and procedure type, the interaction term was not significant (p = 0.09), indicating there was no evidence the risk of complications associated with partial vs radical nephrectomy increased with advancing age. There was no evidence that age was significantly associated with estimated blood loss or operative time.

CONCLUSIONS

We found no evidence that elderly patients experience a proportionally higher complication rate, longer operative times or higher estimated blood loss from partial nephrectomy than do younger patients. Given the advantages of renal function preservation we should expand the use of nephron sparing treatment to renal tumors in elderly patients.

Localized renal cell carcinoma management: an update

OBJECTIVE

To review the current modalities of treatment for localized renal cell carcinoma.

MATERIALS AND METHODS

A literature search for keywords: renal cell carcinoma, radical nephrectomy, nephron sparing surgery, minimally invasive surgery, and cryoablation was performed for the years 2000 through 2008. The most relevant publications were examined.

RESULTS

New epidemiologic data and current treatment of renal cancer were covered. Concerning the treatment of clinically localized disease, the literature supports the standardization of partial nephrectomy and laparoscopic approaches as therapeutic options with better functional results and oncologic success comparable to standard radical resection. Promising initial results are now available for minimally invasive therapies, such as cryotherapy and radiofrequency ablation. Active surveillance has been reported with acceptable results, including for those who are poor surgical candidates.

CONCLUSIONS

This review covers current advances in radical and conservative treatments of localized kidney cancer. The current status of nephron-sparing surgery, ablative therapies, and active surveillance based on natural history has resulted in great progress in the management of localized renal cell carcinoma.

Operative mortality after nephrectomy for renal cell carcinoma

OBJECTIVE

To study the rate and causes of operative and treatment-related mortality after nephrectomy for renal cell carcinoma (RCC) in Iceland.

MATERIAL AND METHODS

This retrospective population-based study included all patients who underwent nephrectomy for RCC in Iceland between 1971 and 2000. Patients who died <30 days after the operation were analyzed and compared to those who survived surgery. Disease stage, tumor size, patient age and preoperative American Society of Anesthesiologists classification were compared between the two groups. Autopsy records were examined to determine the causes of death.

RESULTS

During the study period 880 patients were diagnosed with RCC and 575 (65%) of them underwent a nephrectomy, 116 (20%) with palliative intent. Operative mortality (OM) was 2.8% and did not change during the 30-year period. Patients with OM were significantly older than those without (73 vs 64 years, respectively) but disease stage, tumor size, ASA classification and gender were comparable between the groups. OM was comparable for patients operated on with palliative (3.4%) vs. curative (2.6%) intent (ns). Median time of death was 10 days postoperatively but no patient died intraoperatively. Causes of death were peri- and postoperative bleeding in five patients, infection/sepsis in four, arrhythmia in three, acute renal failure in two, pulmonary embolism in one and multiorgan failure in one.

CONCLUSIONS

OM after nephrectomy for RCC has remained low during the past three decades in Iceland. It is most often caused by perioperative bleeding and infections. We find that the low OM in patients with metastases gives support to the use of palliative nephrectomy as a treatment option when other forms of treatment have failed.

Perioperative morbidity of laparoscopic cryoablation of small renal masses with ultrathin probes: a European multicentre experience

BACKGROUND

Low morbidity has been advocated for cryoablation of small renal masses.

OBJECTIVES

To assess negative perioperative outcomes of laparoscopic renal cryoablation (LRC) with ultrathin cryoprobes and patient, tumour, and operative risk factors for their development.

DESIGN, SETTING, AND PARTICIPANTS

Prospective collection of data on LRC in five centres.

INTERVENTION

LRC.

MEASUREMENTS

Preoperative morbidity was assessed clinically and the American Society of Anaesthesiologists (ASA) score was assigned prospectively. Charlson Comorbidity Index (CCI) and Charlson-Age Comorbidity Index (CACI) scores were retrospectively assigned. Negative outcomes were prospectively recorded and defined as any undesired event during the perioperative period, including complications, with the latter classed according to the Clavien system. Patient, tumour, and operative variables were tested in univariate analysis as risk factors for occurrence of negative outcomes. Significant variables (p<0.05) were entered in a step-forward multivariate logistic regression model to identify independent risk factors for one or more perioperative negative outcomes. The confidence interval was settled at 95%.

RESULTS AND LIMITATIONS

There were 148 procedures in 144 patients. Median age and tumour size were 70.5 yr (range: 32-87) and 2.6 cm (range: 1.0-5.6), respectively. A laparoscopic approach was used in 145 cases (98%). Median ASA, CCI, and CACI scores were 2 (range: 1-3), 2 (range: 0-7), and 4 (range: 0-11), respectively. Comorbidities were present in 79% of patients. Thirty negative outcomes and 28 complications occurred in 25 (17%) and 23 (15.5%) cases, respectively. Only 20% of all complications were Clavien grade > or = 3. Multivariate analysis showed that tumour size in centimetres, the presence of cardiac conditions, and female gender were independent predictors of negative perioperative outcomes occurrence. Receiver operator characteristic curve confirmed the tumour size cut-off of 3.4 cm as an adequate predictor of negative outcomes.

CONCLUSIONS

Perioperative negative outcomes and complications occur in 17% and 15.5%, respectively, of cases treated by LRC with multiple ultrathin needles. Most of the complications are Clavien grade 1 or 2. The presence of cardiac conditions, female gender, and tumour size are independent prognostic factors for the occurrence of a perioperative negative outcome.

Thirty-day mortality after nephrectomy: clinical implications for informed consent

BACKGROUND

The existing literature suggests that the surgical mortality (SM) observed with nephrectomy for localised disease varies from 0.6% to 3.6%.

OBJECTIVE

To examine age- and stage-specific 30-d mortality (TDM) rates after partial or radical nephrectomy.

DESIGN, SETTING, AND PARTICIPANTS

We relied on 24535 assessable patients from the National Cancer Institute (NCI) Surveillance, Epidemiology, and End Results (SEER) database.

MEASUREMENTS

In 12283 patients, logistic regression models were used to develop a tool for pretreatment prediction of the probability of TDM according to individual patient and tumour characteristics. External validation was performed on 12252 patients.

RESULTS AND LIMITATIONS

In the entire cohort of 24535 patients, 219 deaths occurred during the initial 30 d after nephrectomy (0.9% TDM rate). TDM increased with age (≤49 yr: 0.5% vs 50-59 yr: 0.7% vs 60-69 yr: 0.9% vs 70-79 yr: 1.2% vs ≥80 yr: 2.0%; χ(2) trend p<0.001) and stage (0.3% for T1-2N0M0 vs 1.3% for T3-4N0-2M0 vs 4.2% for T1-4N0-2M1; χ2 trend p=<0.001). TDM decreased in more recent years (1988-1993: 1.3% vs 1994-1998: 0.9% vs 1999-2002: 0.7% vs 2003-2004: 0.6%; χ2 trend p<0.001) and was lower after partial versus radical nephrectomy (RN) (0.4% vs 0.9%; p=0.008). Only age (p<0.001) and stage (p<0.001) achieved independent predictor status. The look-up table that relied on the regression coefficients of age and stage reached 79.4% accuracy in the external validation cohort.

CONCLUSIONS

Age and stage are the foremost determinants of TDM after nephrectomy. Our model provides individual probabilities of TDM after nephrectomy, and its use should be highly encouraged during informed consent prior to planned nephrectomy.

Synchronous resections of intra-abdominal pathologies during radical nephrectomy. A case-linked cohort study evaluation of outcomes

OBJECTIVES

We report the outcomes of radical nephrectomy with synchronous surgical resection of intra-abdominal pathologies to guide practice.

PATIENTS AND METHODS

The data of patients requiring radical nephrectomy and surgical resection of a synchronous intra-abdominal pathology over a period of 12 years was extracted on pre-designed data extraction sheets from the case notes and included: age, sex, nature of second intra-abdominal pathology, intra-operative and postoperative details including complications, recurrence rate and survival on follow-up.

RESULTS

Two hundred and ninety patients underwent radical nephrectomy for non-metastatic renal cell carcinoma between January 1995 and January 2007. Amongst these, 30 patients (12%) had an additional surgical resection of a second intra-abdominal pathology at the time of radical nephrectomy. Fifteen underwent radical nephrectomy and surgical resection of a second intra-abdominal non-urological malignancy: colonic tumour - 8, rectal tumour - 3, oesophageal tumour - 2 and gastric tumour - 2. Fifteen patients underwent radical nephrectomy and surgical resection of a synchronous benign intra-abdominal pathology: gall bladder - 8, spleen - 3, uterine fibroid - 1, abdominal aortic aneurysm - 1, colonic polyp - 1 and suspected tumour infiltration of colon - 1. There was a higher morbidity (40%) of radical nephrectomy with synchronous resection of an additional intra-abdominal pathology as compared to radical nephrectomy alone group (25%); however it not was statistically significant (P-value 0.275).

CONCLUSION

It is feasible to offer simultaneous resection of synchronous intra-abdominal pathologies with renal cell carcinoma patients undergoing radical nephrectomy, albeit, at a higher morbidity.

The use of partial nephrectomy in European tertiary care centers

PURPOSE

The objective was to define the trends of PN use over time at six tertiary care European centers.

METHODS

Data were retrieved from institutional databases for patients treated with either PN or radical nephrectomy (RN) for stages T(1-2)N(0)M(0) renal cell carcinoma (RCC) between 1987 and 2007. For purpose of temporal trend analyses patients were divided into five equally sized groups according to the date of surgery. Categorical and multivariable logistic regression analyses assessed predictors of PN use.

RESULTS

Overall 597 (31.7%) patients were treated with PN. Overall, a 4.5-fold increase of PN was recorded. The absolute increases were 41.7-86.3%, 14.9-69.3% and 8.1-35.3% for lesions < or = 2 cm, 2.1-4 cm and 4.1-7 cm (chi-square trend test p<0.001), respectively. In multivariable logistic regression models, decreasing tumor size, younger age, more contemporary date of surgery, male gender and institutional PN rate represented independent predictors of the individual probability of treatment with PN. Lack of data from community hospitals limits the generalizability of our findings.

CONCLUSION

Based on data from six tertiary care centers, the contemporary rate of PN ranges from 86 to 35% for renal masses < or = 2 cm to 4.1-7 cm and is indicative of excellent quality of care.