Partial nephrectomy--contemporary indications, techniques and outcomes

Surgical Experience and Functional Outcomes after Laparoscopic and Robot-Assisted Partial Nephrectomy: Results from a Multi-Institutional Collaboration

Background: In patients treated with partial nephrectomy, prior evidence showed that peri-operative outcomes, such as complications and ischemia time, improved as a function of the surgical experience of the surgeon, but data on functional outcomes after surgery are still scarce. Methods: We retrospectively analyzed data of 4011 patients with a single, unilateral cT1a-b renal mass treated with laparoscopic or robot-assisted partial nephrectomy. The operations were performed by 119 surgeons at 22 participating institutions between 1997 and 2022. Multivariable models investigated the association between surgical experience (number of prior operations) and acute kidney injury (AKI) and recovery of at least 90% of baseline estimated glomerular filtration rate (eGFR) 1 yr after partial nephrectomy. The adjustment for case mix included age, Body Mass Index, preoperative serum creatinine, clinical T stage, PADUA score, warm ischemia time, pathologic tumor size, and year of surgery. Results: A total of 753 (19%) and 3258 (81%) patients underwent laparoscopic and robot-assisted partial nephrectomy, respectively. Overall, 37 (31%) and 55 (46%) surgeons contributed only to laparoscopic and robotic learning curves, respectively, whereas 27 (23%) contributed to the learning curves of both approaches. In the laparoscopic group, 8% and 55% of patients developed AKI and recovered at least 90% of their baseline eGFR, respectively. After adjusting for confounders, we did not find evidence of an association between surgical experience and AKI after laparoscopic partial nephrectomy (odds ratio [OR]: 0.9992; 95% confidence interval [CI]: 0.9963, 1.0022; p = 0.6). Similar results were found when 1-year renal function was the outcome of interest (OR: 0.9996; 95% CI: 0.9988, 1.0005; p = 0.5). Among patients who underwent robot-assisted partial nephrectomy, AKI occurred in 11% of patients, whereas 54% recovered at least 90% of their baseline eGFR. On multivariable analyses, the relationship between surgical experience and AKI after surgery was not statistically significant (OR: 1.0015; 95% CI: 0.9992, 1.0037; p = 0.2), with similar results when the outcome of interest was renal function one year after surgery (OR: 1.0001; 95% CI: 0.9980, 1.0022; p = 0.9). Virtually the same findings were found on sensitivity analyses. Conclusions: In patients treated with laparoscopic or robot-assisted partial nephrectomy, our data suggest that the surgical experience of the operating surgeon might not be a key determinant of functional recovery after surgery. This raises questions about the use of serum markers to assess functional recovery in patients with two kidneys and opens the discussion on what are the key steps of the procedure that allowed surgeons to achieve optimal outcomes since their initial cases.

Partial vs. radical nephrectomy in non-metastatic pT3a kidney cancer patients: a population-based study

BACKGROUND

To test for differences in cancer specific mortality (CSM) rates between radical nephrectomy (RN) and partial nephrectomy (PN) in pT3a nmRCC patients.

METHODS

Within the Surveillance, Epidemiology, and End Results database (2005-2016), 13,177 pT3a patients treated with either PN or RN were identified. Before and after 1:2 ratio propensity score (PS)-match between PN and RN patients, cumulative incidence plot and competing risks regression (CRR) were used to test differences in CSM and other cause mortality (OCM) rates.

RESULTS

Relative to PN (n=1,615, 22.5%), RN patients harbored higher tumor size (72 vs. 38 mm; >70 mm 51 vs.10%), of more aggressive histology, collecting duct (0.4 vs. 0.2%) and sarcomatoid (2.3 vs.0.8%), of higher grade (51.0 vs. 37.5%). After PS-matching and OCM adjustment, 5-year CSM was 3-fold higher after RN than PN (p<0.01). Similarly, after PS matching and CSM adjustment, also 5-year OCM rates were higher after RN (HR: 1.59, p=0.0003).

CONCLUSIONS

PN does not appear to compromise the oncological outcomes in patients with pT3a or high-grade renal masses when compared with RN. Therefore, these concerns should not deter a surgeon from attempting PN when otherwise technically feasible.

Accelerated Recovery After Renal Cell Carcinoma and Partial Nephrectomy With Lifestyle Modifications

Objective and subjective recovery times following a partial nephrectomy may exceed 1 year if patients adhere to the current Western lifestyle. This case demonstrates the rapid recovery of a 59-year-old female who underwent a robotic partial nephrectomy and utilized lifestyle modifications as an adjunct to the treatment of a Stage T1a clear cell renal cell carcinoma. All 6 pillars of lifestyle medicine are incorporated into this patient's recovery plan, which successfully reduced her time to recovery after a partial nephrectomy. This case illustrates how modifications in diet, activity, sleep, stress management, social connectedness, and avoidance of risky substances may shorten recovery time after a partial nephrectomy and may serve as an example that providers can prescribe for patients recovering from other surgeries.

Can Aortic and Renal Arteries Calcium Scores Be New Factors to Predict Post-Operative Renal Function After Nephron Sparing Surgery?

INTRODUCTION

This study aims to investigate whether the calcification of renal arteries and aorta may be risk factors for developing chronic kidney disease (CKD) after Nephron sparing surgery (NSS).

MATERIALS AND METHODS

The patients that underwent either open or laparoscopic NSS from 2000 to 2019 in 4 different centers were retrospectively assessed. Of these patients, 328 had a non-contrast-enhanced computer tomography. Calcium scores of the renal arteries and abdominal aorta were measured in the non-contrast-enhanced images with the calcium score plugin (version 2.0) of Horos™. Univariate and multivariate logistic regression analysis was performed to determine significant risk factors for developing CKD at the last check-up. Roc curve analysis was performed to determine the optimal cut-off values of age and abdominal aorta calcium scores.

RESULTS

A total of 302 patients, of which 52 (16,6%) with CKD and 252 (83,4%) without CKD at the last check-up, were included in the analysis. The mean warm ischemia duration was significantly higher in patients with CKD (18,79±6,72 vs 16,38±5,57 minutes, p=0,016). The mean size of the tumor diameter and the number of the patients with ≥stage T1b were higher in the group with CKD (p=0,024 and 0,005, respectively). The median calcium scores of the aorta and renal arteries were higher in the group with CKD (p<0,001 and p<0,001, respectively). In multivariate analysis, age >60 years (OR:3,65, p=0,022), calcium score of the aorta (OR:4,07, p=0,029), tumor diameter (OR:1,03, p=0,026) and pre-operative CKD stage (OR:10,13, p<0,001) found the be significant factors for predicting last check-up CKD.

CONCLUSION

The calcium score of the aorta may be used as an additional risk factor to predict post-operative CKD risk after NSS with sensitivity over 80%.

Outcomes in robot-assisted partial nephrectomy for imperative vs elective indications

OBJECTIVES

To assess and compare peri-operative outcomes of patients undergoing robot-assisted partial nephrectomy (RAPN) for imperative vs elective indications.

PATIENT AND METHODS

We retrospectively reviewed a multinational database of 3802 adults who underwent RAPN for elective and imperative indications. Laparoscopic or open partial nephrectomy (PN) were excluded. Baseline data for age, gender, body mass index, American Society of Anaesthesiologists score and PADUA score were examined. Patients undergoing RAPN for an imperative indication were matched to those having surgery for an elective indication using propensity scores in a 1:3 ratio. Primary outcomes included organ ischaemic time, operating time, estimated blood loss (EBL), rate of blood transfusions, Clavien-Dindo complications, conversion to radical nephrectomy (RN) and positive surgical margin (PSM) status.

RESULTS

After propensity-score matching for baseline variables, a total of 304 patients (76 imperative vs 228 elective indications) were included in the final analysis. No significant differences were found between groups for ischaemia time (19.9 vs 19.8 min; P = 0.94), operating time (186 vs 180 min; P = 0.55), EBL (217 vs 190 mL; P = 0.43), rate of blood transfusions (2.7% vs 3.7%; P = 0.51), or Clavien-Dindo complications (P = 0.31). A 38.6% (SD 47.9) decrease in Day-1 postoperative estimated glomerular filtration rate was observed in the imperative indication group and an 11.3% (SD 45.1) decrease was observed in the elective indication group (P < 0.005). There were no recorded cases of permanent or temporary dialysis. There were no conversions to RN in the imperative group, and seven conversions (5.6%) in the elective group (P = 0.69). PSMs were seen in 1.4% (1/76) of the imperative group and in 3.3% of the elective group (7/228; P = 0.69).

CONCLUSION

We conclude that RAPN is feasible and safe for imperative indications and demonstrates similar outcomes to those achieved for elective indications.

Development and Validation of a Nomogram Predicting the Prognosis of Renal Cell Carcinoma After Nephrectomy

Objective

To develop and validate a nomogram for predicting the overall survival (OS) of renal cell carcinoma (RCC) patients after nephrectomy.

Materials and Methods

In total, 488 patients with RCC who underwent nephrectomy at the Urology Department of the First Hospital of Shanxi Medical University between January 2013 and December 2018 were randomly divided into a development cohort (n = 344) and a validation cohort (n = 144). The development cohort was used to build a prediction model, and the validation cohort was used for validation. Single-factor and multifactor analyses were carried out with R software, and the nomogram, calibration chart, ROC curve and C index were constructed.

Results

The median follow-up time of the development and validation cohorts was 34 months. The total 3-year and 5-year survival rates of the development cohort were 93.3% and 91.6%, respectively; those of the validation cohort were 92.4% and 91.0%, respectively. Cox univariate analysis of the development cohort showed that age, type 2 diabetes mellitus (T2DM), smoking history, type of surgery, T stage, N stage, M stage and Fuhrman nuclear grade were prognostic factors for OS in RCC patients undergoing nephrectomy. Cox multivariate analysis showed that T2DM, smoking history and T stage were independent prognostic factors for OS in RCC patients undergoing nephrectomy (P < 0.05). According to the univariate and multivariate analyses, a nomogram was constructed. In the development cohort, the C index of predicted OS was 0.875 (95% CI, 0.820-0.930). The calibration curve of the 3-year and 5-year survival rates showed that the predicted value of the nomogram was consistent with the actual observed value. The area under the 3-year and 5-year survival ROC curves was 0.861 and 0.901, respectively. In the validation cohort, the C index was 0.880 (95% CI, 0.778-0.982). The calibration curve of the 3-year and 5-year survival rates showed that the predicted value of the nomogram was consistent with the actual observed value. The area under the 3-year and 5-year survival ROC curves was 0.813 and 0.799, respectively.

Conclusion

We developed and verified a new and accurate nomogram with available clinicopathological data that can effectively predict the OS of RCC patients after nephrectomy.

Hemostatic agent use during partial nephrectomy: trends, outcomes, and associated costs

PURPOSE

To evaluate the ability of hemostatic agents (HA) to limit bleeding complications following partial nephrectomy (PN) and determine HA usage and costs as well as factors associated with post-operative bleeding complications.

METHODS

The records of 429 PN performed for kidney cancers were reviewed for clinical, pathologic, and perioperative variables. Surgical approach, HA use, and HA expenditure were determined. Bleeding complications and management to 90 days after PN were annotated. Wilcoxon rank-sum and two-sample t tests identified factors associated with HA use. Univariate and limited multivariate logistic regression determined variables associated with bleeding complications.

RESULTS

Use of HA was associated with longer OR duration, longer ischemia time, higher EBL, and method of PN (OPN and LPN > RPN) (all p values < 0.001). On bivariate analysis, while multiple factors were associated with bleeding complications, neither HA use (p = 0.924) nor the number of HA used (two agents vs one p = 0.712; three agents vs. one p = 0.606) were. A multivariable model noted that increasing RENAL score (p = 0.013) and surgical approach (OPN vs. RPN [p = 0.009] and LPN vs. RPN (p = 0.002]) were independently associated with bleeding complications, while HA use was not (p = 0.294). During the 16 years of analysis, a total of $77,687 USD was spent on HA. Average annual HA expenditure was $4855 USD with the peak being in 2010 where expense was $14,086. Mean annual costs for HA use were greater for OPN vs RAPN starting in 2013 (p = 0.02) CONCLUSIONS: The use of HA during PN was not associated with lower rates of bleeding complications. Therefore, judicious use in a case-specific manner is requisite to limit potentially unnecessary operative cost.

Comparative study on the curative effect of laparoscopic nephron sparing surgery and renal functions under selective segmental renal artery clamping and main renal artery clamping

Objective:

To discuss the clinical effect and safety evaluation of laparoscopic nephron sparing surgery (LNSS) under selective segmental renal artery clamping (SSRAC) and main renal artery clamping (MRAC).

Methods:

Eighty-four patients with T1 localized renal tumors who were admitted and treated from October 2017 to October 2018 were retrospectively analyzed, and they were classified into the S group (42 patients) and M group (42 patients). The patients in the S group received LNSS under SSRAC, while the patients in the M group received LNSS under MRAC. The duration of the operation, amount of intraoperative blood loss, intraoperative warm ischemia time, duration of postoperative hospital stay and positive rate of incisal edge; the serum creatinine and blood urea nitrogen values before and after the operation; and the occurrence rates of intraoperative and postoperative complications were compared.

Results:

All operations were completed smoothly. No patients had a positive incisal edge, and no patients were converted to MRAC during the operation. The duration of the operation and the amount of intraoperative blood loss increased in the S group compared with the M group. The differences were statistically significant (P <0.05). The differences in the intraoperative warm ischemia time, postoperative drainage and duration of postoperative hospital stay in both groups had no statistical significance (P >0.05). The differences in serum creatinine (SCr) and blood urea nitrogen (BUN) in both groups before the operation had no statistical significance (P >0.05). The SCr and BUN levels significantly increased 1 d and 1 m after the operation. The SCr and BUN levels 1 d and 1 m after the operation were significantly lower in the S group than in the M group, and the differences were statistically significant (P <0.05). The differences in the occurrence rates of intraoperative and postoperative complications in both groups had no statistical significance (P >0.05).

Conclusion:

SSRAC is a new renal artery clamping technology, and its curative effect on LNSS patients is significant. In addition, SSRAC has high safety and little influence on renal functions.

UK Multicenter Prospective Evaluation of the Leibovich Score in Localized Renal Cell Carcinoma: Performance has Altered Over Time

Objective

To examine changes in outcome by the Leibovich score using contemporary and historic cohorts of patients presenting with renal cell carcinoma (RCC)

Patients and Methods

Prospective observational multicenter cohort study, recruiting patients with suspected newly diagnosed RCC. A historical cohort of patients was examined for comparison. Metastasis-free survival (MFS) formed the primary outcome measure. Model discrimination and calibration were evaluated using Cox proportional hazard regression and the Kaplan-Meier method. Overall performance of the Leibovich model was assessed by estimating explained variation.

Results

Seven hundred and six patients were recruited between 2011 and 2014 and RCC confirmed in 608 (86%) patients. Application of the Leibovich score to patients with localized clear cell RCC in this contemporary cohort demonstrated good model discrimination (c-index = 0.77) but suboptimal calibration, with improved MFS for intermediate- and high-risk patients (5-year MFS 85% and 50%, respectively) compared to the original Leibovich cohort (74% and 31%) and a historic (1998-2006) UK cohort (76% and 37%). The proportion of variation in outcome explained by the model is low and has declined over time (28% historic vs 22% contemporary UK cohort).

Conclusion

Prognostic models are widely employed in patients with localized RCC to guide surveillance intensity and clinical trial selection. However, the majority of the variation in outcome remains unexplained by the Leibovich model and, over time, MFS rates among intermediate- and high-risk classified patients have altered. These findings are likely to have implications for all such models used in this setting.

Semi-Autonomous Laparoscopic Robotic Electro-surgery with a Novel 3D Endoscope

This paper reports a robotic laparoscopic surgery system performing electro-surgery on porcine cadaver kidney, and evaluates its accuracy in an open loop control scheme to conduct targeting and cutting tasks guided by a novel 3D endoscope. We describe the design and integration of the novel laparoscopic imaging system that is capable of reconstructing the surgical field using structured light. A targeting task is first performed to determine the average positioning error of the system as guided by the laparoscopic camera. The imaging system is then used to reconstruct the surface of a porcine cadaver kidney, and generate a cutting trajectory with consistent depth. The paper concludes by using the robotic system in open loop control to cut this trajectory using a multi degree of freedom electro-surgical tool. It is demonstrated that for a cutting depth of 3 mm, the robotic surgical system follows the trajectory with an average depth of 2.44 mm and standard deviation of 0.34 mm. The average positional accuracy of the system was 2.74±0.99 mm.

The Effect of Patient and Surgical Characteristics on Renal Function After Partial Nephrectomy

BACKGROUND

The purpose of the study was to identify patient and disease characteristics that have an adverse effect on renal function after partial nephrectomy.

PATIENTS AND METHODS

We conducted a retrospective review of 387 patients who underwent partial nephrectomy for renal tumors between 2006 and 2014. A line plot with a locally weighted scatterplot smoothing was generated to visually assess renal function over time. Univariable and multivariable longitudinal regression analyses incorporated a random intercept and slope to evaluate the association between patient and disease characteristics with renal function after surgery.

RESULTS

Median age was 60 years and most patients were male (255 patients [65.9%]) and white (343 patients [88.6%]). In univariable analysis, advanced age at surgery, larger tumor size, male sex, longer ischemia time, history of smoking, and hypertension were significantly associated with lower preoperative estimated glomerular filtration rate (eGFR). In multivariable analysis, independent predictors of reduced renal function after surgery included advanced age, lower preoperative eGFR, and longer ischemia time. Length of time from surgery was strongly associated with improvement in renal function among all patients.

CONCLUSION

Independent predictors of postoperative decline in renal function include advanced age, lower preoperative eGFR, and longer ischemia time. A substantial number of subjects had recovery in renal function over time after surgery, which continued past the 12-month mark. These findings suggest that patients who undergo partial nephrectomy can experience long-term improvement in renal function. This improvement is most pronounced among younger patients with higher preoperative eGFR.

Early clamp release during laparoscopic partial nephrectomy: Implications for preservation of renal function

INTRODUCTION

Intraoperative warm ischemic time (WIT), associated with hilar clamping during partial nephrectomy (PN), is an established modifiable risk factor for renal dysfunction. We assessed early clamp release (ECR) as a strategy to reduce WIT and assess its impact on renal function and bleeding.

METHODS

We retrospectively assessed patients who underwent minimally invasive PN by a single surgeon at our centre since December 2011. Comparing the standard technique to an ECR modification, WIT, complications, change in estimated glomerular filtration rate (eGFR), and change in differential function as demonstrated by MAG-3 nuclear renography were assessed. Followup blood work and renograms were performed at 6-12 weeks postoperatively and compared to baseline in 70 patients (35 ECR: 35 control).

RESULTS

The ECR and control groups were similar in age, sex, and tumour size, with only patient weight being higher in the ECR group (91.6 vs. 81.6 kg; p<0.05). WIT was significantly lower in ECR group compared to control (18.8 vs. 31.5 minutes; p<0.05). Although there was no significant difference in change from baseline eGFR in the early postoperative period (Day 3) or in followup (6-12 weeks), the control group had a significantly greater loss of ipsilateral renal function from baseline compared to the ECR group (9 vs. 4% change; p<0.05). Blood loss and complication rate were similar between groups.

CONCLUSIONS

The ECR technique offers a safe, reproducible alternative that reduces WIT during laparoscopic PN. ECR demonstrates a reduction in overall ipsilateral renal dysfunction, without increasing complication or intraoperative bleeding risk.

Current Status of Nephron-Sparing Surgery (NSS) in the Management of Renal Tumours

Nephron-sparing surgery has emerged as the surgical treatment of choice for small renal masses over the past two decades, replacing the traditional teaching of radical nephrectomy for renal cell carcinoma. With time, there has been an evolution in the techniques and indications for partial nephrectomy. This review summarizes the current status of nephron-sparing surgery for renal carcinoma and also deals with the future of this procedure.

Histologic subtype needs to be considered after partial nephrectomy in patients with pathologic T1a renal cell carcinoma: papillary vs. clear cell renal cell carcinoma

PURPOSE

We compared the oncological outcomes of papillary renal cell carcinoma (pRCC) with clear cell renal cell carcinoma (ccRCC) after partial nephrectomy (PN) in patients with pathologic T1a RCC.

METHODS

After excluding patients with synchronous multiple renal tumors, familial RCC, and pathologic stage T1b or above, 759 patients with ccRCC and 84 patients with pRCC were included. We assessed the impact of histologic subtypes on oncologic outcomes after PN in patients with pathologic T1a RCC (median follow-up duration, 67 months).

RESULTS

There was no difference in patient and tumor characteristics between the 2 groups, except Fuhrman grade (p = 0.006). Kaplan-Meier analysis identified 5-year recurrence-free survival of 98.7 and 95.6% in patients with ccRCC and pRCC, respectively. However, 10-year recurrence-free survival in patients with ccRCC and pRCC was 96.1 and 73.0%, respectively (p < 0.001). Recurrence ≥5 years post surgery was more common in patients with pRCC compared with those with ccRCC (0.3 vs. 4.8%; p < 0.001). In multivariate analysis, pRCC [hazard ratio (HR) 5.309; p = 0.001] was a significant risk factor for recurrence after PN in patients with pathologic T1a RCC, in addition to larger tumor size (HR 1.861; p = 0.038) and Fuhrman grade ≥3 (HR 5.176; p = 0.003).

CONCLUSIONS

In patients with pathologic T1a RCC, recurrence after PN occurred more commonly in pRCC compared with ccRCC. As over half of the recurrence cases in patients with pRCC occurred ≥5 years post surgery, a longer follow-up time is required, even for those with pathologic stage T1a disease.

Standardized Reporting of Microscopic Renal Tumor Margins: Introduction of the Renal Tumor Capsule Invasion Scoring System

PURPOSE

Renal tumor enucleation allows for maximal parenchymal preservation. Identifying pseudocapsule integrity is critically important in nephron sparing surgery by enucleation. Tumor invasion into and through the capsule may have clinical implications, although it is not routinely commented on in standard pathological reporting. We describe a system to standardize the varying degrees of pseudocapsule invasion and identify predictors of invasion.

MATERIALS AND METHODS

We performed a multicenter retrospective review between 2002 and 2014 at Indiana University Hospital and Loyola University Medical Center. A total of 327 tumors were evaluated following removal via radical nephrectomy, standard margin partial nephrectomy or enucleation partial nephrectomy. Pathologists scored tumors using our i-Cap (invasion of pseudocapsule) scoring system. Multivariate analysis was done to determine predictors of higher score tumors.

RESULTS

Tumor characteristics were similar among surgical resection groups. Enucleated tumors tended to have thinner pseudocapsule rims but not higher i-Cap scores. Rates of complete capsular invasion, scored as i-Cap 3, were similar among the surgical techniques, comprising 22% of the overall cohort. Papillary histology along with increasing tumor grade was predictive of an i-Cap 3 score.

CONCLUSIONS

A capsule invasion scoring system is useful to classify renal cell carcinoma pseudocapsule integrity. i-Cap scores appear to be independent of surgical technique. Complete capsular invasion is most common in papillary and high grade tumors. Further work is warranted regarding the relevance of capsular invasion depth as it relates to the oncologic outcome for local recurrence and disease specific survival.

Spherical cap surface model: A novel method for predicting renal function after partial nephrectomy

OBJECTIVES

To estimate the percent functional volume preservation from preoperative images using a novel method, the spherical cap surface model, and to investigate whether this model can preoperatively predict renal function after partial nephrectomy.

METHODS

A total of 233 patients with renal cell carcinoma who underwent open or laparoscopic partial nephrectomy between January 2011 and December 2013 were included in the present study. The spherical cap surface model was used to calculate the estimated percent functional volume preservation on preoperative computed tomography, and the estimated percent functional volume preservation was multiplied by the preoperative estimated glomerular filtration rate to predict the postoperative estimated glomerular filtration rate. The occurrence of acute kidney injury also served as an outcome. Univariate and multivariate linear regression, and receiver operating characteristic curve analysis were used to test the model.

RESULTS

The estimated percent functional volume preservation calculated by the novel model was significantly associated with both nadir percent estimated glomerular filtration rate preservation and late percent estimated glomerular filtration rate preservation in the multivariate analysis (the P-values were 0.021 and 0.043, respectively). Receiver operating characteristic curve analysis for predicting acute kidney injury after partial nephrectomy showed that volume preservation (P < 0.001) and warm ischemia time (P = 0.040) were both significant. Regarding the ability to predict a significant decrease in late renal function after partial nephrectomy, only volume preservation (P = 0.044) was significant.

CONCLUSIONS

Preservation of functional volume is the primary determinant of functional outcomes after partial nephrectomy. The spherical cap surface model seems to represent a promising tool to predict nadir and late postoperative renal function in patients undergoing partial nephrectomy.

Nephron-sparing surgery in renal cell carcinoma: current perspectives on technical issues

Surgical resection remains the standard treatment for renal cell carcinoma. Although historically the concept of wide excision of the affected kidney dictated surgical thinking for more than half a century, a better understanding of the biology of this tumor, standardized staging, and changing patterns of presentation permit today a refined management approach with nephron-sparing surgery, thus limiting potential long-term morbidity by maximizing the preservation of functional renal parenchyma. This paper aims to review the current status of nephron-sparing surgery for solid renal masses with an emphasis on indications, preoperative assessment, and operative technical issues, summarizing the most recent existing data on the subject.

Outcomes of open partial nephrectomies performed by Australian trainees

BACKGROUND

Partial nephrectomy (PN) has become the standard of care for small renal tumours, with open partial nephrectomy (OPN) being superseded by minimally invasive PN. Advances in minimal access surgery have resulted in fewer relative contraindications, with subsequently fewer OPN being performed. Consequentially, trainees have less opportunity to gain skills and experience in open renal surgery. The aims of this study were to assess the standard of OPN performed by Australian urological trainees and to define whether OPN is a safe and suitable training opportunity.

METHOD

A retrospective review was undertaken on patients who underwent OPN performed by urology trainees from 2010 to 2014 at two training hospitals in Western Australia. Data collected included patient demographics, surgical and oncological outcomes and morbidity.

RESULTS

Sixty patients underwent OPN, with a mean age of 56 years. Most tumours were single, with mean size 31 mm. Mean operative time was 157 min, with a mean cold ischaemic time of 27 min. Mean pre- and post-operative creatinine levels were equivalent (77 μmol/L). The overall complication rate was 18%, with no documented urinary leaks, and 1.7% blood transfusion rate. Median length of stay was 4 days. There were no oncological positive margins or recurrence after a median follow-up of 2 years.

CONCLUSION

Our data support the notion that Australian urological trainees can perform the majority of OPN cases, with equivalent oncological outcomes. We would advocate that when an OPN is being performed, the supervising consultant should use the case as an adjuvant for open renal surgery training.

Zero ischemia robotic-assisted partial nephrectomy in Alberta: Initial results of a novel approach

INTRODUCTION

Partial nephrectomy remains the standard of care in early stage, organ-confined renal tumours. Recent evidence suggests that minimally invasive surgery can proceed without segmental vessel clamping. In this study, we review our experience at a Canadian centre with zero ischemia robotic-assisted partial nephrectomy (RAPN).

METHODS

A retrospective chart review of zero ischemia RAPN was performed. All surgeries were consecutive partial nephrectomies performed by the same surgeon at a tertiary care centre in Northern Alberta. The mean follow-up period was 28 months. These outcomes were compared against the current standards for zero ischemia (as outlined by the University of Southern California Institute of Urology [USC]).

RESULTS

We included 21 patients who underwent zero ischemia RAPN between January 2012 and June 2013. Baseline data were similar to contemporary studies. Twelve (57.1%) required no vascular clamping, 7 (33.3%) required clamping of a single segmental artery, and 2 (9.5%) required clamping of two segmental arteries. We achieved an average estimated blood loss of 158 cc, with a 9.2% average increase in creatinine postoperatively. Operating time and duration of hospital stay were short at 153 minutes and 2.2 days, respectively.

CONCLUSION

Zero ischemia partial nephrectomy was a viable option at our institution with favourable results in terms of intra-operative blood loss and postoperative creatinine change compared to results from contemporary standard zero ischemia studies (USC). To our knowledge, this is the first study to review an initial experience with the zero ischemia protocol in robotic-assisted partial nephrectomies at a Canadian hospital.

A Study of Relationship of Atheroembolic Risk Factors with Postoperative Recovery in Renal Function after Partial Nephrectomy in Patients Staged T1-2 Renal Cell Carcinoma during Median 4-Year Follow-up

Purpose

The objective of this study is to evaluate the relationship of atheroembolic risk factors with postoperative recovery of renal function after on-clamp partial nephrectomy (PN) with warm ischemia in patients with staged T1-2 renal cell carcinoma (RCC).

Materials and Methods

A total of 234 patients from 2004 to 2012 were included, and their clinicopathologic and operative parameters, including atheroembolic risk factors were reviewed retrospectively. Renal function, as determined by estimated glomerular filtration rate (eGFR) and measurement of serum creatinine level (Cr) at each scheduled follow-up for a median four years, was compared between the high-risk (HR) group (n=49, ≥ five risk factors) and the low-risk (LR) group (n=185, < five risk factors).

Results

Except for baseline renal function and number of risk factors for atheroembolism, differences in characteristics between groups were comparatively insignificant. At 3 months after the operation, Cr and eGFR differed significantly between the two groups (p < 0.05), but no differences were observed afterward. Significant deterioration from baseline in Cr and eGFR was observed in both groups at 1 month after the operation, with a greater change in the HR group (p < 0.05). From measurement to measurement, significantly faster deterioration in Cr and eGFR was observed in the HR group than in the LR group until 6 months after the operation (Cr: LR, 0.02 mg/dL and HR, 0.13 mg/dL; eGFR: LR, 1.50 mL/min/1.73 m² and HR, 6.38 mL/min/1.73 m²; p < 0.05).

Conclusion

The presence of atheroembolic risk factors may negatively influence postoperative recovery of renal function after PN in patients with localized RCC.

Safety and Postoperative Outcomes of Regional versus Global Ischemia for Partial Nephrectomy: A Systematic Review and Meta-Analysis

OBJECTIVE

To analyze current evidence comparing the safety and outcomes of regional and global ischemia for partial nephrectomy (PN).

MATERIALS AND METHODS

A systematic search of the PubMed and Web of Science databases was conducted in May 2014 to identify studies comparing the safety and outcomes of regional and global ischemia for PN. A systematic review and meta-analysis was also performed.

RESULTS

Six retrospective observational studies were selected for the analysis, including 363 patients who underwent PN (162 regional ischemia and 201 global ischemia cases). Operation times were not statistically different [weighted mean difference (WMD) = 20.35 min, 95% CI: -0.28-40.97, p = 0.05], but estimated blood loss was significantly higher in the regional ischemia group (WMD = 52.04 ml, 95% CI: 14.30-89.78, p = 0.007) than in the global ischemia group. Complication rates [odds ratio (OR) = 1.16; 95% CI: 0.63-2.15, p = 0.63] and blood transfusion rates (OR = 1.85; 95% CI: 0.86-4.01, p = 0.12) of the two groups were not significantly different. The regional ischemia group showed better postoperative renal function (WMD = 4.23 ml/min, 95% CI: 2.61-5.85, p < 0.00001) than the global ischemia group, and all cases in the regional ischemia group showed negative margins.

CONCLUSIONS

Regional ischemia is as safe to perform as global ischemia, and the former leads to better postoperative renal functions than the latter. These findings support the application of regional ischemia for PN.

Simultaneous bilateral robotic partial nephrectomy: Case report and critical evaluation of the technique

We report our first simultaneous bilateral robot assisted partial nephrectomy (RAPN) in order to show and critically discuss the feasibility of this procedure. Materials and methods A 69-year-old male patient visited our department due to incidental finding of bilateral mesorenal small masses (2.5 cm on the right and 3.5 cm on the left) suspicious for malignancy. We started from the right side with patient in flank position. Port placement: 12-mm periumbilical camera port, two 8-mm robotic ports in wide ‘‘V’’configuration, additional 12 mm assistant port on the midline between the umbilicus and symphysis pubis. A right unclamping RAPN with sliding clip renorrhaphy was performed. The trocars were removed and the robot undocked. Without interrupting the anesthesiological procedures, the patient was reported in supine position and, after 180 degrees rotation of the surgical bed, was newly placed in contralateral flank position. Using both the previous periumbilical and midline ports, two other 8-mm robotic trocars were placed. The robot was then redocked and RAPN was also performed on the left side using the same previously reported technique. Results Total time: 285 min. Estimated blood losses: 150 cc. Postoperative period: uneventful. Pathological examination: bilateral renal cell carcinoma, negative surgical margins. Conclusions Our experience was encouraging and confirmed the feasibility and safety of this procedure. The planning of our technique was time and cost effective with cosmetic benefit for the patient. However, we think that an appropriate selection of the patients and a skill in robotic renal surgery are advisable before approaching this type of surgery.

The impact of non-hilar clamping open partial technique performed for the treatment of patients with small renal masses with lower R.E.N.A.L. nephrometry scores on renal functions during the early postoperative period

OBJECTIVE

Herein, the impact of off-clamp open partial nephrectomy on early postoperative period renal functions were evaluated in patients with low RENAL nephrometry scoring small renal masses.

MATERIAL AND METHODS

Twenty-three patients (12 women, and 11 men) who had undergone non-hilar clamping open partial nephrectomy in our clinic between the years 2010, and 2013 were retrospectively evaluated. Mean age, body mass index (BMI), operative time, blood loss, renal nephrometry score, mean hospital stay, pre-, and postoperative serum creatinine (Cr), and glomerular filtration rate (GFR) of the patients were assessed.

RESULTS

Mean age, BMI, tumor size, and preoperative renal nephrometry scores were 56.09±10.49 years (36-70 yrs), 24.81±2.44 kg/m(2), 3.68±1.125 cm, and 6.41±1.77 pts, respectively. Mean operative time, intraoperative blood loss, and hospital stay were detected as 139.14±33.60 min, 274.9±77.02 mL, and 4.27±1.12 days, respectively. Preoperative mean serum Cr, and GFR levels were 0.804±0.216 mg/dL, and 93.97±25.83 mL/min/1.73 m(2), respectively. Postoperative 1. day mean serum Cr, and GFR levels were 0.896±0.25 mg/dL, and 85.94±28.85 mL/min/1,73 m(2), while corresponding 3. month-values were 0.81±0.205 mg/dL, and 93.59±21.00 mL/dk/1.73 m(2), respectively. A statistically significant difference was not found between preoperative, and postoperative 3. month- serum Cr, and GFR levels. However, postoperative 3. month-serum Cr, and GFR levels were lower than corresponding values estimated on postoperative 1. day (p<0.016).

CONCLUSION

One of the important considerations in partial nephrectomy is to preserve renal functions. Therefore, non-hilar clamping open partial nephrectomy should be taken into consideration for surgeons unexperienced especially in laparoscopic surgery with its lower morbidity, and complication rates.

Laparoscopic radical and partial nephrectomy: The clinical efficacy and acceptance of the techniques

The laparoscopic approach has been established as the surgical procedure of choice for radical nephrectomy during the recent years. The advantages of the laparoscopic radical nephrectomy in comparison to the open approach are well-documented. The oncological results of the laparoscopic approach are similar to the open procedure while the post-operative morbidity is lower. Laparoscopic partial nephrectomy seems to gain ground to its open counterpart, as the accumulation of experience in the technique grows. In this review, a PubMed search in the latest literature on radical and partial laparoscopic nephrectomy took place and the outcome of the search is presented. Several issues about the surgical techniques and clinical efficacy are discussed. In addition, the preliminary experience in laparoscopic nephrectomy of one of the authoring institutions is also presented.

Enhanced computed tomography after partial nephrectomy in early postoperative period to detect asymptomatic renal artery pseudoaneurysm

OBJECTIVES

We systematically examined the incidence and potential implications of renal artery pseudoaneurysm occurring after partial nephrectomy detected by computed tomography screening in the early postoperative period.

METHODS

Between January and December 2012, 117 patients underwent enhanced screening computed tomography on the fourth postoperative day after partial nephrectomy to evaluate for renal artery pseudoaneurysm. The size of the renal artery pseudoaneurysm and follow-up imaging were utilized to decide on pre-emptive angioembolization. Patient characteristics, tumor specifics and surgical data were analyzed.

RESULTS

A total of 17 of 117 patients (15%) were found to have renal artery pseudoaneurysm on early postoperative computed tomography. Renal artery pseudoaneurysm occurred in nine of 73 open partial nephrectomy patients (12.3%) and eight of 44 laparoscopic partial nephrectomy patients (18.2%). One early patient experienced a postoperative bleed on postoperative day 9 after diagnosis of a 3.5-mm diameter renal artery pseudoaneurysm on postoperative day 3, and this patient was successfully managed with angioembolization. There were no other postoperative bleeding episodes. Rapid growth of a renal artery pseudoaneurysm was observed in a second patient who was treated with pre-emptive angioembolization. Five patients were diagnosed with small renal artery pseudoaneurysm (2-4 mm) on postoperative day 4 and observed with follow-up imaging showing resolution of the renal artery pseudoaneurysm. Another 10 patients were diagnosed with larger renal artery pseudoaneurysm (≥4 mm) and were managed with pre-emptive angioembolization.

CONCLUSIONS

Early postoperative computed tomography screening is able to detect modest rates of asymptomatic renal artery pseudoaneurysm. The rate of postoperative bleed remained low with a policy of selective angioembolization. Renal artery pseudoaneurysm size and interval enlargement might indicate the risk of rupture. Further studies are required to assess the potential role of pre-emptive angioembolization.