Simple Enucleation for the Treatment of PT1a Renal Cell Carcinoma: Our 20-Year Experience

Exploring the Characteristics of Circulating Tumor DNA in Pt1a Clear Cell Renal Cell Carcinoma: A Pilot Study

Circulating tumor DNA (ctDNA) is a promising biomarker for clear cell renal cell carcinoma (ccRCC); however, its characteristics in small renal masses of ccRCC remain unclear. In this pilot study, we explored the characteristics of ctDNA in pT1a ccRCC. Plasma samples were collected preoperatively from 53 patients with pT1a ccRCC. The ctDNA of pT1a ccRCC was profiled using next-generation sequencing and compared with that of higher-stage ccRCC. The association of ctDNA in pT1a ccRCC with clinicopathological features was investigated. The positive relationship of mutations between ctDNA and matched tissues was evaluated. In pT1a ccRCC, the ctDNA detection rate, cell-free DNA concentration, and median variant allele frequency were 20.8%, 5.8 ng/mL, and 0.38%, respectively, which were significantly lower than those in metastatic ccRCC. The ctDNA gene proportions in pT1a samples differed from those in metastatic ccRCC samples. The relationships between ctDNA and tumor size, tumor grade, and patient age were not elucidated. The positive concordance between ctDNA and matched tissues was poor for pT1a ccRCC. Strategies are needed to increase sensitivity while eliminating noise caused by clonal hematopoiesis to increase the clinical utility of ctDNA analysis in small renal masses of ccRCC.

Robotic-assisted tumor enucleation versus robotic-assisted partial nephrectomy for intermediate and high complexity renal cell carcinoma: a single-institution experience

OBJECTIVES

To compare the perioperative and oncological outcomes of robotic-assisted tumor enucleation (RATE) and robotic-assisted partial nephrectomy (RAPN) in the treatment of intermediate and high complexity renal cell carcinoma (RCC).

METHODS

We retrospectively collected the data of 359 patients with intermediate and high complexity RCC who underwent RATE and RAPN. The perioperative, oncological, and pathological outcomes of the two groups were compared, and univariate and multivariate analyses were used to evaluate the risk factors for warm ischemia time (WIT) > 25 min.

RESULTS

Compared with RAPN group, patients in RATE group had shorter operative time (P < 0.001), shorter WIT (P < 0.001), and less estimated blood loss (EBL) (P < 0.001). The decrease rate of estimated glomerular filtration rate (eGFR) in RATE group was better than that in RAPN group (P < 0.001). Multivariable analysis showed that RAPN and higher PADUA score were independent risk factors for WIT > 25 min (both P < 0.001). The rate of positive surgical margin was similar between the two groups, but the local recurrence rate of the RATE group was higher than that of the RAPN group (P = 0.027).

CONCLUSIONS

RATE and RAPN have similar oncological outcomes for the treatment of intermediate and high complexity RCC. In addition, RATE was superior to RAPN in perioperative outcomes.

Imaging Features of Renal Masses to Select Optimal Candidates for Tumor Enucleation Partial Nephrectomy

PURPOSE OF REVIEW

The goal of this paper was to critically evaluate preoperative findings that optimally select candidates for renal tumor enucleation partial nephrectomy.

RECENT FINDINGS

Tumor enucleation has been widely accepted as a management option for patients with chronic kidney disease, hereditary renal cell carcinoma, or multifocal disease. Recent evidence suggests safety and efficacy in the management of routine small renal masses. With recent advances in imaging, the literature for ruling out aggressive renal cell carcinoma and selection for tumor enucleation is robust. As the incidence of renal cell carcinoma rises, partial nephrectomy continues to be the mainstay of treatment for localized renal cell carcinoma. Tumor enucleation maximizes preservation of renal parenchyma without hindering oncologic outcomes. It is important to recognize key tumor radiologic findings which urologists may use to optimize patient selection for tumor enucleation.

Comparison of Tumor Enucleation and Standard Partial Nephrectomy According to Trifecta Outcomes: A Multicenter Study by the Turkish Academy of Urology, Uro-Oncology Working Group

INTRODUCTION

We aimed to evaluate the impact of the resection technique (tumor enucleation (TE) or standard partial nephrectomy (SPN)) on trifecta outcomes in patients having undergone partial nephrectomy (PN).

MATERIALS AND METHODS

We retrospectively analyzed the clinical and pathologic parameters in patients with localized renal cell carcinoma (pT1-2N0M0) who had undergone PN between January 2001-December 2018 at one of 15 different tertiary referral centers. Multivariable logistic regression analysis was applied to investigate independent predictors of trifecta failure, decreased postoperative renal functions (decreased estimated glomerular filtration rate (eGFR) > 10%), perioperative complications (Clavien-Dindo > 1), and positive surgical margins.

RESULTS

A total of 1070 patients with a mean age 56.11 ± 11.88 years were included in our study. PN was performed with TE in 848 (79.25%) and SPN in 222 (20.75%) patients. Trifecta failure rate was 56.2% for TE and 64.4% for SPN (p = 0.028). On multivariable analysis, TE was associated with less trifecta failure (p = 0.025) and eGFR decrease >10% rates (p = 0.024). On the other hand, there was no statistically significant difference between TE and SPN according to positive surgical margins (p = 0.450) and complication > Clavien-Dindo grade 1 (p = 0.888) rates. The only independent predictive factor for complications > Clavien-Dindo 1 was the Charlson comorbidity index (CCI) (p = 0.001).

CONCLUSION

TE is associated with less trifecta failure than SPN. This result is mainly due to better preservation of renal function with TE.

Surgical Insights for the Management of Variant Histology in Renal Cell Carcinoma

Purpose:

To review the current literature regarding variant (non-clear) histology of renal cell carcinoma (RCC) and the clinical management of these renal tumors.

Material and Methods:

A PubMed database search was performed in May 2020 focusing on variant RCC, its diagnosis and associated syndromes, tumor characteristics, and options for management.

Results:

A broad range of pathological, clinical and diagnostic characteristics amongst non-ccRCC variants were found to have an impact on the overall management of these tumors. The imaging modalities, frequency of surveillance, and timing for intervention were found to be dependent on the type of genetic alterations, type of histology, and tumor growth rates. The timing and type of surgery as well as the systemic therapy are tailored to the specific tumor type and patient.

Conclusion:

The findings of this review suggest that clinical management should be considered and adjusted for patients with non-ccRCC histological variants based on tumor subtype and genetic alterations.

Greater Renal Function Benefit from Enucleation Technique for More Complex Renal Tumors in Robot-Assisted Partial Nephrectomy

Background: Tumor enucleation technique in robot-assisted partial nephrectomy (RAPN) reportedly contributes to renal function preservation. Which tumors and which part to utilize this technique have not been determined. Patients and Methods: This multi-institutional retrospective study included patients who underwent RAPN at tertiary surgery centers. Patients were first stratified into High, Intermediate, and Low categories based on renal nephrometry score. Patients were further classified into I/B-enucleation (I/B-E, I + B ≤ 1) and I/B-resection (I/B-R, I + B ≥ 2) groups based on surface-intermediate-base margin score. Perioperative outcomes, including percentile change in estimated glomerular filtration rate (eGFR), new-onset chronic kidney disease, complication rate, surgical margin, and trifecta achievement, were compared between the I/B-E and I/B-R groups in each category. Odds ratios (ORs) and β-coefficients were also compared. Results: Overall, 704 patients were included in this study. Relative decrease in eGFR was significantly lower for the I/B-E group in all three categories, with medians of 8.1%, 4.4%, and 3.2% in the High, Intermediate, and Low, respectively. In multivariate analyses, excision technique was independently associated with eGFR change in all three. β-coefficient was higher in the High (5.06) category than in the Low (3.17) or Intermediate (3.33). Across all three categories, significantly more patients attained trifecta with a difference of 34.0%, 18.3%, and 15.1% in the High, Intermediate, and Low categories, respectively (all, p < 0.05), with a higher OR in the High (5.91) category than in the Low (3.20) or Intermediate (2.48). No significant differences were found in operation time, amount of estimated blood loss, rate of positive surgical margin, or complications. Warm ischemic time was significantly longer for the I/B-E group in the Intermediate (18.0 minutes vs 16.0 minutes, p = 0.002) and Low categories (13.0 vs 11.0, p = 0.006), but not significant in High (p = 0.344). Conclusions: I/B-enucleation in RAPN contributes to renal function preservation, and the impact was more emphasized in complex tumors.

Cause-Specific Mortality Among Survivors From T1N0M0 Renal Cell Carcinoma: A Registry-Based Cohort Study

Objective

More T1N0M0 renal cell carcinoma (RCC) is detected and the prognosis has improved, but, the current focus on non-RCC-related mortality is superficial. We investigated cause-specific mortality and its temporal patterns after an RCC diagnosis.

Methods

In the Surveillance, Epidemiology, and End Results-18 database, patients with T1N0M0 RCC treated with partial nephrectomy (PN) or radical nephrectomy (RN) during 2000-15 were identified. Standardized mortality ratios (SMRs) for cause of death were calculated. Risk predictors for each cause-specific mortality were investigated using the Fine and Gray sub-distribution model.

Results

In all, 68,612 eligible patients were pooled. A total of 14,047 (20.5%) patients had died (cardiovascular disease [CVD], 28.3%; other non-cancer-related diseases, 20.3%; RCC, 18.7%; other cancer types, 16.3%; non-disease events, 16.1%) during follow-up. Heart disease, diabetes mellitus, and cerebrovascular disease were the primary causes of non-RCC-related mortality within 1 year after the diagnosis. The greatest proportion of death (39.0%) occurred within 1-5 years after the diagnosis, mostly due to RCC itself, followed by heart disease. However, >5 years after the diagnosis, heart disease became the leading cause of death. Compared with the general US population, a 21% (SMR, 1.21; 95%CI 1.19-1.23) increased risk of all-mortality was observed; RCC patients had a higher risk of heart disease-related death within 5-10 years (SMR, 1.10; 95%CI 1.04-1.17) and >10 years (1.12; 1.02-1.22) after the diagnosis. Older age and RN increased the death risk of CVD and RCC-specific mortality. Although a larger tumor diameter increased the risk of RCC-specific death, this was not a significant predictor for CVD. Moreover, for T1N0M0 RCC tumors of diameter >4 cm, there was no significant difference in CVD incidence for RN vs. PN.

Conclusions

RCC-specific mortality is a common challenge for the prognosis. Importantly, a large proportion and higher SMRs of other non-RCC-related diseases (especially CVD) should not be disregarded for the better holistic management of survivors of local RCC. Targeted prevention strategies for non-RCC-related death could lead to significant reductions in mortality for RCC survivors.

Long-Term Oncologic Outcomes After Laparoscopic and Robotic Tumor Enucleation for Renal Cell Carcinoma

OBJECTIVES

Tumor enucleation (TE) optimizes parenchymal preservation with promising short-term oncologic outcomes compared with standard partial nephrectomy (SPN). However, researches/literatures about long-term oncologic outcomes for TE after minimally invasive surgery are scarce. We aim to analyze long-term oncologic outcomes after laparoscopic and robotic tumor enucleation for renal cell carcinoma (RCC).

PATIENTS AND METHODS

We retrospectively analyzed 146 patients who underwent TE with either laparoscopic or robotic approach for localized RCC in our center. Local recurrence, cancer specific survival (CSS), recurrence free survival (RFS), and overall survival (OS) were the main outcomes. Survival curves were generated using a Kaplan-Meier method. Perioperative outcomes and pathological outcomes were also analyzed.

RESULTS

Overall, 98 male and 48 female patients were eligible for the study. The median tumor size was 3.4 cm with a median R.E.N.A.L. score of seven. Warm ischemia was used in 143 patients with a median ischemia time of 20 min and three patients had zero ischemia. Five patients (3.4%) had major complications (> Clavien IIIa) and only two were related to urinary system. The median global glomerular filtration rate (GFR) preserved after surgery was 93%. Pseudocapsule invasion was reported in 50 tumors (34%) and positive surgical margins were found in 3/146 (2.1%) tumors. At a median follow-up of 66 months, local recurrence happened in two patients (1.4%), and systemic recurrence happened in six patients (4.2%). The 5-year CSS, RFS, OS were 95.7, 89.6, and 91.9%, and the 10-year CSS, RFS, OS were 93.8, 89.6, and 90.0%, respectively.

CONCLUSION

This study indicates that tumor enucleation with laparoscopic or robotic approach in experienced hands for the treatment of RCC appears oncologically safe with a median follow-up of more than 5 years. Prospective studies with more patients and longer follow-up will be required to further evaluate oncologic safety after TE.

Kidney ventrally rotation technique in retroperitoneal robot-assisted partial nephrectomy for posterior hilar tumor: technical feasibility and preliminary results

PURPOSE

The retroperitoneal robotic assisted partial nephrectomy (RAPN) is suitable for tumors locating on the posterior side of the kidney. However, the posterior hilar tumor poses an additional surgical challenge due to the special location and poor tumor exposure. We developed a novel kidney ventrally rotation technique to overcome this difficulty during retroperitoneal RAPN and evaluated its efficacy in a retrospective case-control comparative study.

METHODS

From March 2016 to April 2019, a total of 39 patients with posterior renal hilar tumor underwent retroperitoneal RAPN. The kidney ventrally rotation technique, which improved the tumor exposure by opening the peritoneum and rotating the kidney ventrally, was applied in 24 cases, and the conventional RAPN was performed in the other 15 cases (control group). Perioperative data was analyzed to evaluate the efficacy of the kidney ventrally rotation technique.

RESULTS

In kidney rotation group, the 24 patients underwent RAPN successfully without converting to open surgery or radical nephrectomy. The warm ischemia time was 17.4 ± 6.6 min, which was significantly shorter than 24.5 ± 8.3 min in control group. The mean operation time (80 ± 24 min) and estimated blood loss (104 ± 65 ml) were not different from the control group. No sever complications occurred, and no positive surgical margin was found in all the malignant cases. After 14 months follow-up, no recurrence or metastasis occurred in all cases.

CONCLUSION

Kidney ventrally rotation technique is safe and feasible for improving the exposure of posterior renal hilar tumor during retroperitoneal RAPN. It could be regarded as an efficient option for the management of posterior hilar tumor.

A preoperative nomogram predicting the pseudocapsule status in localized renal cell carcinoma

Background

Tumor enucleation (TE) surgery for localized renal cell carcinoma (RCC) relies on a complete peritumoral pseudocapsule (PC). Study objective was to develop a preoperative model to predict PC status.

Methods

The prediction model was developed in a cohort that consisted of 170 patients with localized RCC, and data was gathered from 2010 to 2015. Multivariable logistic regression analysis and R were used to generate this prediction model. The statistical performance was assessed with respect to the calibration, discrimination, and clinical usefulness.

Results

The prediction model incorporated the systemic inflammatory markers [neutrophil-lymphocyte ratio (NLR); albumin-globulin ratio (AGR)], CT imaging features (tumor size and necrosis), and clinical risk factors (BMI). The model showed good discrimination, with a C-index of 0.85 (0.78–0.91), and good calibration (P=0.60). The sensitivity and specificity were 62% and 94% respectively. Decision curves and clinical impact curve demonstrated that the current model was clinically useful.

Conclusions

We constructed a model that incorporated both the systematic inflammatory markers and clinical risk factors. It can be conveniently used to preoperatively predict the individualized risk of PC invasion and identify the best candidates to receive TE surgery.

Inherited kidney cancer syndromes

PURPOSE OF REVIEW

To describe current paradigms for genetic testing, screening, and treatment of patients with inherited kidney cancer syndromes.

RECENT FINDINGS

We describe various new aspects of hereditary kidney cancer. Recent data now support that hereditary kidney cancer may account for 5-8% of kidney cancers diagnosed. Methods of testing have evolved including the introduction of multigene next-generation sequencing panels. We continue to learn more about the natural history and management of classic hereditary cancer syndromes. New emerging conditions with lower kidney cancer penetrance have been recognized adding the growing list of syndromes associated with kidney cancer development. The surgical management strategies of enucleation remain however systemic therapy options are being explored both for localized and advanced settings.

SUMMARY

Genetic predisposition to kidney cancer is likely more common than once thought. Knowledge of clinical manifestation and genetic testing strategies are needed to properly identify and treat patient and their families.

Renal cell cancer treatment: an expert panel recommendation from the Latin American cooperative group-genitourinary and the Latin American renal cancer group: focus on surgery

Background:

Renal cell cancer (RCC) is one of the 10 most common cancers in the world, and its incidence is increasing, whereas mortality is declining only in developed countries. Therefore, two collaborative groups, The Latin American Oncology Cooperative Group-Genitourinary Section (LACOG-GU) and the Latin American Renal Cancer Group (LARCG), held a consensus meeting to develop this guideline.

Methods:

Issues (134) related to the treatment of RCC were previously formulated by a panel of experts. The voting panel comprised 26 specialists (urologists and medical oncologists) from the LACOG-GU/LARCG. A consensus was reached if 75% agreement was achieved. If there was less concordance, a new discussion was undertaken, and a consensus was determined by the most votes after a second voting session.

Results:

The expert meeting provided recommendations that were in line with the global literature; 75.0% of the recommendations made by the panel of experts were evidence-based level A, 22.5% of the recommendations were level B, and 2.5% of the recommendations were level D.

Conclusions:

This review suggests recommendations for the surgical treatment of RCC according to the LACOG-GU/LARCG experts.

Effect of histopathologic characteristics on pseudocapsular invasion in the case of partial nephrectomy for renal tumours

OBJECTIVE

It is aimed to define the existence of pseudocapsular structure on renal tumours, illuminate the relation between pseudocapsular invasion and Fuhrman grade histological type that are among histopathologic prognostic risk factors and determine the relation between surgical margin positivity and existence of pseudocapsular invasion. Sequential partial nephrectomy series and relevant pathological preparations were retrospectively reviewed in order to evaluate these issues.

METHODS

The study includes 123 patients diagnosed with T1 renal tumour and treated with partial nephrectomy in between January 2007 and June 2016. Benign angiomyolipoma was excluded due to complete non-existence of pseudocapsule. 99 T1 patients diagnosed with renal cell cancer whose pathological slides can be duly analysed were included in the study. Clinical and pathological details were evaluated for all patients. Existence of pseudocapsule was revealed for all patients. Pseudocapsule invasion was classified by existence of expansive and infiltrative type and non-existence of pseudocapsule invasion. The groups have been assessed by their histopathologic characteristics.

RESULTS

Compared to the group in which pseudocapsular invasion was not detected, clear-cell histological subtype was observed more frequently in a statistically significant way in the group with expansive pseudocapsular invasion and infiltrative pseudocapsular invasion respectively (p = 0.017 and p < 0.001). Pathological tumour sizes were found out to be statistically similar (p = 0.874). There was not a statistically significant difference in terms of Fuhrman grade (p = 0.220). There was not a statistically significant difference in terms of surgical positive margin (p = 0.609).

CONCLUSION

It was indicated in our study that only the histological subtype affected pseudocapsular invasion in group of patients treated with partial nephrectomy but tumour size, tumour stage, tumour location as well as endophytic and exophytic character did not affect invasion. It has also been revealed that surgical margin positivity is not correlated with pseudocapsular invasion.

Endoscopic Robot-assisted Simple Enucleation Versus Laparoscopic Simple Enucleation With Single-layer Renorrhaphy in Localized Renal Tumors: A Propensity Score-matched Analysis From a High-volume Centre

OBJECTIVE

To compare perioperative results and early oncological outcomes of endoscopic robot-assisted simple enucleation (ERASE) and laparoscopic simple enucleation (LSE) by using a propensity score-matched analysis.

METHODS

We evaluated 383 patients who underwent transperitoneal ERASE or LSE for renal tumors from November 2012 to October 2016. Propensity score matching was performed on age, gender, body mass index, Eastern Cooperative Oncology Group score, tumor side and size, preoperative estimated GFR and PADUA score.

RESULTS

In total, 278 and 105 patients underwent ERASE and LSE, respectively. The PADUA score was ≥10 for 61 (21.9%) and 13 (12.4%), respectively (P = .034). After matching, mean operative time and warm ischemic time were significantly lower with ERASE than LSE (171.9 vs 188.2 minutes; P = 0.016 and 20.9 vs 24.2 minutes; P = .001). The estimated mean blood loss was similar (167.7 vs 183.3 mL; P = .315). The conversion rate to open surgery or radical nephrectomy was similar with ERASE and LSE (1.0% vs 5.0%, P = .214) and the rate of intraoperative complications was lower (2.0% vs 8.9%, P = .030). The overall incidence of positive surgical margins was similar (P = .614). The median follow-up was less for ERASE than LSE patients (22 vs 38 months). Recurrence did not differ between the 2 groups: 2 ERASE cases (2.0%) versus 4 LSE cases (4.0%) (P = .679).

CONCLUSION

ERASE is a safe and acceptable alternative to LSE. ERASE appears to confer shorter operative time, shorter warm ischemic time and lower rate of intraoperative complication.

Perioperative outcomes of zero ischemia radiofrequency ablation-assisted tumor enucleation for renal cell carcinoma: results of 182 patients

BACKGROUND

To evaluate the perioperative outcomes of zero ischemia radiofrequency ablation-assisted tumor enucleation.

METHODS

Patients undergoing zero ischemia radiofrequency ablation-assisted tumor enucleation were retrospectively identified from July 2008 to March 2013. The tumor was enucleated after RFA treatment. R.E.N.A.L., PADUA and centrality index (C-index) score systems were used to assess each tumor case. We analyzed the correlation of perioperative outcomes with these scores. Postoperative complications were graded with Clavien-Dindo system. Multivariate logistic regression analyses were used to assess risk of complications.

RESULTS

Among 182 patients assessed, median tumor size, estimated blood loss, hospital stay and operative time were 3.2 cm (IQR 2.8-3.4), 80 ml (IQR 50-120), 7 days (IQR 6-8) and 100 min (IQR 90-120), respectively. All three scoring systems were strongly correlated with estimated blood loss, hospital stay and operative time. We found 3 (1.6%) intraoperative and 23 (12.6%, 13 [7.1%] Grade 1 and 10 [5.5%] Grade 2 & 3a) postoperative complications. The median follow-up was 55.5 months (IQR 45-70). Additionally, the complexities of R.E.N.A.L., PADUA and C-index scores were significantly correlated with complication grades (P < 0.001; P < 0.001; P < 0.001; respectively). As the representative, R.E.N.A.L. score was an independent predictive factor for postoperative complications and patients with a high complexity had an over 24-fold higher risk compared to those with a low complexity (OR 24.360, 95% CI 4.412-134.493, P < 0.001).

CONCLUSIONS

Zero ischemia radiofrequency ablation-assisted tumor enucleation is considered an effective nephron-sparing treatment. Scoring systems could be useful for predicting perioperative outcomes of radiofrequency ablation-assisted tumor enucleation.

Positive surgical margins are predictors of local recurrence in conservative kidney surgery for pT1 tumors

OBJECTIVES

The clinical significance of positive surgical margin (PSM) after a Nephron Sparing Surgery (NSS) is controversial. The aim of this study is to evaluate the association between PSM and the risk of disease recurrence in patients with pT1 kidney tumors who underwent NSS.

MATERIALS AND METHODS

Retrospective cohort study. A total of 314 patients submitted to a NSS due to stage pT1 renal tumor between January 2010 and June 2015 were included. Recurrence-free survival was estimated. The Cox model was used to adjust the tumor size, histological grade, pathological stage, age, surgical margins and type of approach.

RESULTS

Overall PSM was 6.3% (n=22). Recurrence was evidenced in 9.1% (n=2) of patients with PSM and 3.5% (n=10) for the group of negative surgical margin (NSM). The estimated local recurrence-free survival rate at 3 years was 96.4% (95% CI 91.9 to 100) for the NSM group and 87.8% (95% CI 71.9 to 100) for PSM group (p=0.02) with no difference in metastasis-free survival. The PSM and pathological high grade (Fuhrman grade III or IV) were independent predictors of local recurrence in the multivariate analysis (HR 12.9, 95%CI 1.8-94, p=0.011 / HR 38.3, 95%CI 3.1-467, p=0.004 respectively). Fuhrman grade proved to be predictor of distant recurrence (HR 8.1, 95%CI 1.6-39.7, p=0.011).

CONCLUSIONS

The PSM in pT1 renal tumors showed to have higher risk of local recurrence and thus, worse oncological prognosis.

Histopathologic analysis of tumor bed and peritumoral pseudocapsule after in vitro tumor enucleation on radical nephrectomy specimen for clinical T1b renal cell carcinoma

PURPOSE

This study was designed to assess the feasibility and histopathologic safety of tumor enucleation for renal cell carcinoma, through histopathologic analysis of the tumor bed and peritumoral pseudocapsule (PC) after in vitro tumor enucleation.

MATERIALS AND METHODS

We studied 176 radical nephrectomy specimens for clinical T1b renal cell carcinoma in our institution, from January 2013-February 2016. Immediately after the kidney was excised, the tumor of radical specimen was enucleated in vitro. The tumor bed parenchyma of 15mm beyond the PC was examined to investigate the possible presence of tumor invasion or satellite lesions. The PC invasion was also evaluated.

RESULTS

The average tumor size was 5.7±0.7cm. The histopathologic evaluation revealed that 68.2% of tumors were clear cell renal cell carcinoma (RCC). The pathological staging showed that 92.6% of tumors were pT1b, 2.8% were pT2, and 4.5% were pT3a. For clinical T1b RCC, tumor infiltration on tumor bed was detected in 6 cases (3.4%), and satellite lesion was detected in 3 (1.7%). In the group of grade 1 to 2, 4 (2.3%) were found with residual tumor, and 5 (2.8%) in the group of grade 3 to 4 (P = 0.133). Papillary RCC had the highest rate of residual tumors (8.8%). A statistically significant association of peritumoral PC invasion with tumor size and pathologic grade was observed. Median follow-up was 23 months (range: 6-43) with a recurrence rate of 6.3% (11 of 176) and a cancer-specific mortality rate of 2.8% (5 of 176).

CONCLUSIONS

For clinical T1b renal cell carcinoma, the risks of tumor infiltration or satellite lesions on enucleation tumor bed or both are relatively low. Peritumoral PC invasion is associated with tumor size and pathologic stage. Tumor enucleation is a histopathologically safe technique for patients undergoing partial nephrectomy.

Outcomes of robot-assisted simple enucleation of renal masses: A single European center experience

The aim of this study was to assess the ability of pre-and intraoperative parameters, to predict the risk of perioperative complications after robot-assisted laparoscopic simple enucleation (RASE) of renal masses, and to evaluate the rate of trifecta achievement of this approach stratifying the cohort according to the use of ischemia during the enucleation.From April 2009 to June 2016, 129 patients underwent RASE at our Institution. We stratified the procedures in 2 groups: clamping and clamp-less RASE. After RASE, all specimens were retrospectively reviewed to assess the surface-intermediate-base (SIB) scoring system. Patients were followed-up according to the European Association of Urology guidelines recommendations. All pre-, intra-, and postoperative outcomes were prospectively collected in a customized database and retrospectively analyzed.A total of 112 (86.8%) patients underwent a pure RASE and 17 (13.2%) had a hybrid according to SIB classification system. The mean age was 61.17 years. In 21 patients (16.3%), complications occurred, 13 (61.9%) were Clavien 1 and 2, while 8 were Clavien 3a and b complications. Statistical significant association with complications was found in patients with American Society of Anestesiology (ASA) score 3 (44.5%, P = .04), longer mean operative time (OT) 195 versus 161.36 minutes (P =.03), mean postoperative hemoglobin (Hb) 10.1 versus 11.8 (P <.001), and mean ΔHb 3.59 versus 2.18 (P <.001). In multivariate logistic regression, only longer OT and ΔHb were statistical significant predictive factors for complications. In sub-group analysis, clamp-less RASE was safe in terms of complications (14.1%), positive surgical margins (1.3%), and mid-term local recurrence (1.3%). Although in this approach there is higher EBL (P = .01), this had no impact on ΔHb (P = .28). A clamp-less approach was associated with a higher rate of SIB 0 (71.8% vs 51%, P = .02), higher trifecta achievement (84.6% vs 62.7%, P = .004), and better impact on serum creatinine (mean 0.83 vs 0.91, P = .01).RASE of renal tumors is a safe technique with very good postoperative outcomes. Complication rate is low and associated with ASA score >3, longer OT, and ΔHb. RASE is suitable for the clamp-less approach, which allows to perform easier the pure enucleation (SIB 0) and to obtain higher rates of trifecta outcomes.

Nephron Sparing for Renal Cell Carcinoma: Whenever Possible?

Open studies have definitely and repeatedly favoured nephron-sparing surgery in improving overall, cancer-specific, and cardiac disease-specific survival in cases with a normal contralateral kidney. However, the only randomised clinical trial could not confirm this superiority of nephron-sparing surgery over radical nephrectomy.

Functional Implications of Renal Tumor Enucleation Relative to Standard Partial Nephrectomy

OBJECTIVE

To compare the surgical precision for optimizing nephron-mass preservation of tumor enucleation (TE) vs standard partial nephrectomy (SPN), with primary focus on functional outcomes. TE is presumed to optimize preservation of parenchymal mass and function but this has not yet been rigorously studied and quantified.

MATERIALS AND METHODS

Robotic partial nephrectomy patients who had appropriate pre- and postoperative studies for analysis of parenchymal mass preservation specific to the operated kidney were included. Computed tomography or magnetic resonance imaging and estimated glomerular filtration rate were required to be <2 months prior and 4-12 months after surgery. Parenchymal mass preservation and surgical precision were estimated for each technique, with precision defined as actual postoperative parenchymal volume or predicted postoperative parenchymal volume, presuming loss of a 5 mm rim of parenchyma associated with tumor excision and reconstruction.

RESULTS

Analysis included 57 TE and 53 SPN. Median age, body mass index, and tumor size were comparable. Percent parenchymal mass preserved in the operated kidney with TE was 96% (interquartile range [IQR] = 90-100) vs 89% (IQR = 83-96) for SPN (P = .003). Precision of excision or reconstruction was 101% (IQR = 96-105) for TE vs 94% (IQR = 88-100) for SPN (P < .001). On multivariable analysis, only TE correlated with improved surgical precision (coefficient = 6.7, 95% confidence interval = 1.6-11.8, P = .01). Although preservation of global renal function also favored TE, the differences were marginal (96% vs 93%), and statistical significance was not observed (P = .2).

CONCLUSION

Our analysis, which specifically focuses on the functional implications of TE, demonstrates that TE maximally spares normal parenchyma compared to SPN. Thus far, functional differences remain marginal and not statistically significant. Clinical significance of these findings in various clinical settings will require further investigation.

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.

Ring Suture Technique in Retroperitoneal Laparoscopic Partial Nephrectomy for Hilar Cancer: A New Renorrhaphy Technique

BACKGROUND AND PURPOSE

To evaluate the safety and efficacy of a ring suture technique during retroperitoneal laparoscopic partial nephrectomy (RLPN) for management of renal cell carcinoma (RCC) in the renal hilum.

PATIENTS AND METHODS

Data for patients with renal hilar cancer who underwent RLPN from January 2010 to March 2015 were collected. All surgeries involved the ring suture technique, following the same procedure: the renal artery was dissected and clamped, the tumor was enucleated from the kidney, defects of the vascular and collecting system were repaired, and then the edge of the renal parenchyma was sutured continuously along the border. Finally, the renal artery clamp was removed, and any injury of the vascular system was repaired if necessary. We retrospectively analyzed renal ischemic time, blood loss, and postoperative complications.

RESULTS

Among the 17 patients, 11 were male (median age 61 years, range 42-71 years). Mean tumor diameter was 3.4 ± 0.9 cm and median R.E.N.A.L. nephrometry score was 8 (range 6-10). The mean warm ischemic time was 23.0 ± 9.2 minutes and median blood loss during surgery was 110 mL (range 70-350 mL); we had no case of uncontrollable massive bleeding. Radical nephrectomy was used in one case because of tumor embolus in a branch of the renal vein. All patients recovered well following surgery. Pathology confirmed the diagnosis of RCC in all cases, with the main subtype clear-cell carcinomas (88.2%).

CONCLUSIONS

The ring suture technique is safe and effective for management of renal hilar cancer during RLPN for selected patients.

Tumor Enucleation for Renal Cell Carcinoma

The increased number of small renal masses (SRMs) detected annually has led to a rise in the use of nephron-sparing surgery (NSS). These techniques aim to preserve the largest amount of healthy renal tissue possible while maintaining the same oncologic outcomes as radical nephrectomy (RN). Additionally, partial nephrectomy (PN) has been linked to a lower risk of chronic kidney disease, cardiovascular morbidity, and mortality when compared to RN. There has been continual progress toward resecting less renal parenchyma. While the predominant surgical method of performing NSS is through traditional PN, simple enucleation (SE) of the tumor has increased in popularity over recent years. SE is a technique that aims to preserve the maximal amount of renal parenchyma possible by utilizing the renal tumor pseudocapsule to bluntly separate the lesion from its underlying parenchyma, offering the smallest possible margin of excised healthy renal tissue. Several studies have demonstrated the oncological safety of SE compared with PN in the treatment of SRMs, with lower overall incidence of positive surgical margins. Additionally, SE has been shown to have similar 5- and 10-year progression-free and cancer-specific survival as PN. We present a review of the literature and an argument for SE to be a routine consideration in the treatment of all renal tumors amenable to NSS.

Significance of Pathologic T3a Upstaging in Clinical T1 Renal Masses Undergoing Nephrectomy

BACKGROUND

The objectives of the present study were to report the incidence of pathologic T3a upstaging in a contemporary cohort of patients with clinical stage T1 (cT1) renal tumors treated with partial or radical nephrectomy; investigate the clinical outcomes; and identify the predictors associated with pathologic upstaging.

MATERIALS AND METHODS

From a single-institution, institutional review board-approved renal tumor database of 945 patients, we identified 610 patients who had undergone surgery for a cT1 renal mass. Data for 494 patients were available for analysis. Of these, 66 lesions had been pathologically upstaged to T3a after surgery and 428 had not. The oncologic follow-up data and clinical and pathologic features were recorded, and multivariable logistic regression analysis was performed to identify the risk factors for pT3a upstaging, controlling for age, gender, body mass index, and nephrectomy type.

RESULTS

The cT1 tumors of 66 patients (13.3%) were upstaged to pT3a after surgery. Of these 66 patients, 44 (66.7%) had undergone partial and 22 (33.3%) radical nephrectomy. The median follow-up period was 50 months. No patient with upstaging developed recurrence, and all were disease free at their last follow-up visit. On multivariable analysis, tumor size > 4 cm (odds ratio [OR], 3.766; 95% confidence interval [CI], 1.417-10.011; P < .008), clear cell histologic features (OR, 4.461; 95% CI, 1.498-13.461; P < .007), and positive surgical margins (hazard ratio, 5.118; 95% CI, 2.088-12.547; P < .0001) were associated with upstaging.

CONCLUSION

Of the cT1 lesions in 66 patients, 13% were pathologically upstaged after surgery. The patients with larger tumors, clear cell histologic features, and positive surgical margins were at the greatest risk of upstaging. However, after an intermediate follow-up period, pathologic upstaging did not appear to result in worsened oncologic outcomes.

Positive surgical margins in nephron-sparing surgery: risk factors and therapeutic consequences

The increased use of nephron-sparing surgery to treat localized renal cell carcinoma (RCC) lends weight to the question of the value of microscopically positive surgical margins (PSM) in cases with a tumor bed macroscopically free of residual tumor. The aim of this article is to highlight the data available on risk factors for PSM, their clinical relevance, and possible therapeutic consequences. For this purpose, publications on the incidence and relevance of PSM after partial nephrectomy from the last 15 years were examined and evaluated. We summarize that PSM are generally rare, regardless of the surgical procedure, and are seen more often in connection with an imperative indication for nephron-sparing surgery as well as a central tumor location. Most studies describe that PSM lead to a moderate increase in the rate of local relapses, but no study has thus far been able to demonstrate an association with shorter tumor-specific overall survival. Intraoperative frozen section analysis had no positive influence on the risk of definite PSM in most trials. Therefore, we conclude that PSM should definitely be avoided. However, in cases with a macroscopically tumor-free intraoperative resection bed, they should lead to close surveillance of the affected kidney and not to immediate (re)intervention.

Robotic nephron-sparing surgery for renal tumors: Current status

There have been a number of advances in robotic partial nephrectomy (RPN) for renal masses. We reviewed these advances with emphasis on the evolution of technique and outcomes as well as the expanding indications for RPN. Literature in the English language was reviewed using the National Library of Medicine database. Relevant articles were extracted, and their citations were utilized to broaden our search. The identified articles were reviewed and summarized with a focus on novel developments. RPN is an evolving procedure and is an emerging viable alternative to laparoscopic partial nephrectomy and open partial nephrectomy with favorable outcomes. The contemporary techniques used for RPN demonstrate excellent perioperative outcomes. The short-term oncologic outcomes are comparable to those of laparoscopic and open surgical approaches. Further studies are needed to assess long-term oncologic control.

Standardized reporting of resection technique during nephron-sparing surgery: the surface-intermediate-base margin score

A standardized reporting system of nephron-sparing surgery resection techniques is lacking. The surface-intermediate-base scoring system represents a formal reporting instrument to assist in interpretation of reported data and to facilitate comparisons in the urologic literature.

[Positive surgical margins in nephron sparing surgery for renal cell carcinoma]

Nephron sparing surgery (NSS) with a minimal tumor-free margin is considered the cornerstone in the contemporary management of renal cell carcinoma (RCC) stage T1. The aim of this study is to review incidence, predictive risk factors, clinical significance and oncologic outcomes of positive surgical margins (PSM) in NSS. English articles published before March 2014 have been searched in Medline Databank.PSM are present in 0-7% of patients in all surgical approaches considered. Some predictive factors,such as tumor size, localization, and histology have been identified in the past. Other topics concerning surgical technique and approach are discussed.The majority of patients with PSM do not experience disease recurrence and PSM impact on overall survival and cancer-specific survival seems to be irrelevant. These results lead to more conservative clinical strategies. However, an active surveillance is mandatory for all patients with PSM and especially for those with high risk disease. Generalization of these results is limited by the low level of evidence of available studies. Further efforts are necessary to avoid PSM intraoperatively and to provide prospective information in order to standardize the postoperative management.

Hereditary renal cell carcinoma: genetics, clinical features, and surgical considerations

OBJECTIVES

Hereditary renal cancer syndromes have been described and have illuminated novel methods to treat sporadic renal cell carcinoma. In this work, we aimed to review the genetic basis, molecular pathology and clinical manifestations of hereditary syndromes, as well as outline principles of surgical management and use of targeted therapy.

METHODS

We performed a comprehensive review of selected peer-reviewed publications regarding hereditary renal cancer syndromes, their genetic basis, and recommendations for surgical management.

RESULTS

The major syndromes contributing to hereditary renal cell carcinoma are discussed along with relevant literature guiding their management. The evolving surgical and molecular treatments are discussed.

CONCLUSIONS

Identification of genetic basis of hereditary carcinomas provides opportunity for targeted therapy of metastatic sporadic renal cell carcinoma. Appropriate and timely surgical management of hereditary renal cancers decreases the possibility of development of metastatic disease, and allows for preservation of renal function despite the need for repeat surgical interventions.

Analysis of surgical complications of renal tumor enucleation with standardized instruments and external validation of PADUA classification

PURPOSE

To assess surgical results and morbidity of tumor enucleation (TE), and to evaluate their correlation with PADUA nephrometric score.

METHODS

We prospectively gathered data, including accurate analysis of tumor nephrometry, from 244 consecutive patients treated with TE for clinically localized renal cell carcinoma. All surgical results were collected, and perioperative complications were stratified for severity according to Clavien system. Correlation between preoperative variables and surgical results/complications was assessed with uni- and multivariate analysis.

RESULTS

Mean (range) tumor size was 3.6 (0.8-10.0) cm, and mean (range) warm ischemia time was 16.8 (5-35) min. Overall, perioperative complications occurred in 45 patients (18.4 %), and of those 8 were medical and 37 were surgical (4 Clavien grade 1, 25 grade 2, and 8 grade 3) complications. Urine leakage rate was 2.0 %. No grade 4/5 complications occurred in this series. At univariate analysis PADUA score, endophytic tumor growth, tumor diameter, involvement of UCS and renal sinus resulted associated with warm ischemia time (p < 0.0001 each) and surgical complications (p = 0.0007, p = 0.049, p = 0.021, p = 0.036, and p = 0.029, respectively). At logistic regression, nephrometry score resulted independently associated with overall complications (related risk for each increased point 1.54; p = 0.017), surgical complications (related risk 1.58; p = 0.016), and Clavien grade 3 surgical complications (related risk 2.99; p = 0.008).

CONCLUSIONS

The TE technique was associated with a 15.2 % surgical complication rate with a 3.3 % reintervention rate (including ureteral stenting and superselective renal artery embolization). Tumor nephrometry and surgical indication resulted independent predictors of Clavien grade 3 complications. The PADUA score is a reliable tool to predict surgical results and morbidity of TE.

Positive surgical margins after nephron-sparing surgery for renal cell carcinoma: incidence, clinical impact, and management

Nephron-sparing surgery (NSS) for renal cell carcinoma (RCC) offers comparable oncologic results but a lower risk of chronic kidney disease when compared with radical nephrectomy; however it can result in positive surgical margins (PSMs) and consequently to a possible risk of oncologic failure. The aim of this review is to evaluate the incidence of PSMs after nephron-sparing surgery, to assess their clinical and oncologic impact, and to provide an overview of the possible therapeutic management. We performed a nonsystematic review of the literature in the MEDLINE database using the following keywords: partial nephrectomy, nephron-sparing surgery, and positive margin. We reviewed articles published only in English from January 2002 to May 2012. The overall incidence of PSMs after NSS ranges from 0% to 7%, with no significant differences in open, laparoscopic, and robot-assisted techniques. Smaller tumor size could result in a higher risk of PSMs. Even if there is not a clear agreement in the clinical evidence, local recurrence seems to be more likely in patients with PSMs, especially in those with high-grade tumors. Development of metastases and cancer-specific survival, as seen in midterm follow-up studies, seems to be comparable to those in patients with negative surgical margins. Considering the globally low risk of local recurrence, development of metastasis, or cancer-specific mortality, careful surveillance could be the best management option for most patients with PSMs after NSS.

Zero ischemia laparoscopic radio frequency ablation assisted enucleation of renal cell carcinoma: experience with 42 patients

PURPOSE

We evaluated the safety and efficacy of zero ischemia, radio frequency ablation assisted tumor enucleation for renal cell carcinoma. We report the incidence of complications, positive surgical margins, local recurrence, and progression-free and disease specific survival rates.

MATERIALS AND METHODS

We retrospectively reviewed data on 42 patients with renal cell carcinoma treated with zero ischemia laparoscopic radio frequency ablation assisted tumor enucleation between March 2006 and November 2009. Median age was 60 years (range 37 to 82) and 31 patients (73.8%) were male. The median greatest tumor dimension was 3.4 cm (range 1.8 to 6.1). The Mann-Whitney U, chi-square and Fisher exact tests were used to compare bleeding and complications. The paired t and Mann-Whitney U tests were used to compare glomerular filtration rates. The Kaplan-Meier method was used to calculate survival.

RESULTS

We found 32 tumors with a greatest dimension of 4 cm or less and 10 with a greatest dimension of 4 to 7 cm. Median blood loss was 82.5 ml (range 15 to 210). Overall 7 complications (16.6%) occurred, including postoperative fever in 4 cases (Clavien grade II) and prolonged urinary leakage in 3 (Clavien grade III). The PADUA (preoperative aspects and dimensions used for an anatomical) score was associated with prolonged urinary leakage (p = 0.03) but not with overall complications. No patient had positive surgical margins. The glomerular filtration rate did not differ before vs 12 months after surgery. Three-year cancer specific, cumulative and progression-free survival was 100%, 97.3% and 96.4%, respectively.

CONCLUSIONS

Zero ischemia, laparoscopic radio frequency ablation assisted tumor enucleation of renal cell carcinoma is a safe, effective nephron sparing treatment that provides excellent oncological and functional outcomes.