Surgical margin does not influence recurrence rate in pT1 clear cell renal cell carcinoma after partial nephrectomy: A multicenter study

Relevance of Positive Surgical Margins in Localized Renal Cell Carcinoma After Surgical Resection: Predictive Factors and Survival Implications

INTRODUCTION

The implications of positive surgical margins (PSM) after surgery for renal cell carcinoma (RCC) remain subject of discussion. This study aimed to identify risk factors for PSM, assess its effect on overall survival (OS), and determine predictors of OS.

PATIENTS AND METHODS

Data from RCC surgeries at Mannheim University Medical Center between 2010 and 2023 was analyzed. Propensity score matching balanced PSM and control groups using age, surgical approach, tumor stage, histological subtype, and American Association of Anesthesiologists (ASA) score. Logistic and cox regression models predict PSM and OS, respectively. Kaplan-Meier analysis compared OS of PSM patients and controls.

RESULTS

A total of 1066 RCC patients were included. Propensity score matching yielded 32 PSM patients and 96 controls. Multivariable logistic regression identified tumor stage ≥ T3a (odds ratio [OR] = 2.74, 95% confidence interval [CI] = 1.0-6.8, P = .04) and chromophobe, compared to clear cell, RCC (OR = 3.19, 95% CI = 1.0-8.7, P = .03) as independent predictors of PSM. Multivariable cox regression found age > 65 years (hazard ratio [HR] = 2.65, 95% CI = 1.7-4.2, P < .01) and tumor stage ≥ T3a (HR = 2.25, 95% CI = 1.4-3.7, P < .01) to predict shorter OS. Partial vs. radical nephrectomy was associated with improved OS (HR = 0.49, 95% CI = 0.3-0.9, P = .02). Kaplan-Meier analysis revealed no OS difference between PSM patients and controls (P = .49) over a 45-month median follow-up.

CONCLUSION

PSM is not a primary determinant of inferior survival, while age and tumor stage play a more prominent role. A well-calibrated follow-up protocol for PSM patients, combining PSM with coinciding factors such as tumor stage, grade, size, or PSM extent, is crucial for adequate surveillance while preventing excessive interventions.

Role of clinicopathological variables in predicting recurrence and survival outcomes after surgery for non-metastatic renal cell carcinoma: Systematic review and meta-analysis

Renal cell carcinoma (RCC) represents 2% of all diagnosed malignancies worldwide, with disease recurrence affecting 20% to 40% of patients. Existing prognostic recurrence models based on clinicopathological features continue to be a subject of controversy. In this meta-analysis, we summarized research findings that explored the correlation between clinicopathological characteristics and post-surgery survival outcomes in non-metastatic RCC patients. Our analysis incorporates 99 publications spanning 140 568 patients. The study's main findings indicate that the following clinicopathological characteristics were associated with unfavorable survival outcomes: T stage, tumor grade, tumor size, lymph node involvement, tumor necrosis, sarcomatoid features, positive surgical margins (PSM), lymphovascular invasion (LVI), early recurrence, constitutional symptoms, poor performance status (PS), low hemoglobin level, high body-mass index (BMI), diabetes mellitus (DM) and hypertension. All of which emerged as predictors for poor recurrence-free survival (RFS) and cancer-specific survival. Clear cell (CC) subtype, urinary collecting system invasion (UCSI), capsular penetration, perinephric fat invasion, renal vein invasion (RVI) and increased C-reactive protein (CRP) were all associated with poor RFS. In contrast, age, sex, tumor laterality, nephrectomy type and approach had no impact on survival outcomes. As part of an additional analysis, we attempted to assess the association between these characteristics and late recurrences (relapses occurring more than 5 years after surgery). Nevertheless, we did not find any prediction capabilities for late disease recurrences among any of the features examined. Our findings highlight the prognostic significance of various clinicopathological characteristics potentially aiding in the identification of high-risk RCC patients and enhancing the development of more precise prediction models.

Positive surgical margins may not affect the survival of patients with renal cell carcinoma after partial nephrectomy: A meta-analysis based on 39 studies

Background

So far, whether positive surgical margin(PSM) has adverse effects on the prognosis of patients is still controversial, so we designed this study to systematically evaluate the effect of PSM on the prognosis of patients with renal cell carcinoma (RCC) after partial nephrectomy (PN).

Methods

On the basis of three electronic databases (PubMed, Embase and the Cochrane Library) up to May 2022, all case-control studies (CCSs) comparing the effects of PSM and negative surgical margin (NSM) after PN on the oncological results of RCC patients were included. Two evaluators independently conducted a systematic literature search and extracted the data we needed. The methodological quality of all studies was evaluated by the modified Newcastle-Ottawa scale. The odds ratio (OR) was used to describe the results for dichotomous variables, and the meta-analysis was conducted using Cochrane Review Manager 5.2 and Stata 14.2.

Results

A total of 39 studies involving 21461 patients were included in our meta-analysis. The pooled results showed that the rates of tumor recurrence (OR 3.93, 95% CI 2.95-5.24; p < 0.00001) and metastasis (OR 4.63, 95% CI 3.11-6.88; p < 0.00001) in the PSM group were significantly higher than those in the NSM group. However, there were no significant differences in the rates of all-cause death (OR 1.35, 95% CI 0.92-1.99; p = 0.13) or cancer-specific death (OR 0.99, 95% CI 0.51-1.94; p = 0.99) between the two groups. In addition, subgroup analyses were carried out according to different average follow-ups, which revealed similar results.

Conclusion

Insignificant differences in survival between the PSM and NSM groups were observed, although significant differences in recurrence and metastasis in the PSM group were reported. Our study supported that close monitoring might be another effective choice for patients with PSM after PN. Considering the possible limitations, we recommended cautious interpretation of our results.

Current strategies to diagnose and manage of positive surgical margins and local recurrence after partial nephrectomy

Objective

No standard strategy for diagnosis and management of positive surgical margin (PSM) and local recurrence after partial nephrectomy (PN) are reported in literature. This review aims to provide an overview of the current strategies and further perspectives on this patient setting.

Methods

A non-systematic review of the literature was completed. The research included the most updated articles (about the last 10 years).

Results

Techniques for diagnosing PSMs during PN include intraoperative frozen section, imprinting cytology, and other specific tools. No clear evidence is reported about these methods. Regarding PSM management, active surveillance with a combination of imaging and laboratory evaluation is the first option line followed by surgery. Regarding local recurrence management, surgery is the primary curative approach when possible but it may be technically difficult due to anatomy resultant from previous PN. In this scenario, thermal ablation (TA) may have the potential to circumvent these limitations representing a less invasive alternative. Salvage surgery represents a valid option; six studies analyzed the outcomes of nephrectomy on local recurrence after PN with three of these focused on robotic approach. Overall, complication rates of salvage surgery are higher compared to TA but ablation presents a higher recurrence rate up to 25% of cases that can often be managed with repeat ablation.

Conclusion

Controversy still exists surrounding the best strategy for management and diagnosis of patients with PSMs or local recurrence after PN. Active surveillance is likely to be the optimal first-line management option for most patients with PSMs. Ablation and salvage surgery both represent valid options in patients with local recurrence after PN. Conversely, salvage PN and radical nephrectomy have fewer recurrences but are associated with a higher complication rate compared to TA. In this scenario, robotic surgery plays an important role in improving salvage PN and radical nephrectomy outcomes.

Surgical margins after partial nephrectomy as prognostic factor for the risk of local recurrence in pT1 RCC: a systematic review and narrative synthesis

Purpose

To systematically review the published literature on surgical margins as a risk factor for local recurrence (LR) in patients undergoing partial nephrectomy (PN) for pT1 renal cell carcinomas (RCC).

Evidence acquisition

A systematic literature search of relevant databases (MEDLINE, Embase and the Cochrane Library) was performed according to the PRISMA criteria up to February 2022. The hypothesis was developed using the PPO method (Patients = patients with pT1 RCC undergoing PN, Prognostic factor = positive surgical margins (PSM) detected on final pathology versus negative surgical margins (NSM) and Outcome = LR diagnosed on follow-up imaging). The primary outcome was the rate of PSM and LR. The risk of bias was assessed by the QUIPS tool.

Evidence synthesis

After assessing 1525 abstracts and 409 full-text articles, eight studies met the inclusion criteria. The percentage of PSM ranged between 0 and 34.3%. In these patients with PSM, LR varied between 0 and 9.1%, whereas only 0–1.5% of LR were found in the NSM-group. The calculated odds ratio (95% confident intervals) varied between 0.04 [0.00–0.79] and 0.27 [0.01–4.76] and was statistically significant in two studies (0.14 [0.02–0.80] and 0.04 [0.00–0.79]). The quality analysis of the included studies resulted in an overall intermediate to high risk of bias and the level of evidence was overall very low. A meta-analysis was considered unsuitable due to the high heterogeneity between the included studies.

Conclusion

PSM after PN in patients with pT1 RCC is associated with a higher risk of LR. However, the evidence has significant limitations and caution should be taken with the interpretation of this data.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00345-022-04016-0.

Long-Term Oncological and Functional Outcomes After Robot-Assisted Partial Nephrectomy for Clinically Localized Renal Cell Carcinoma

BACKGROUND

To evaluate long-term oncological and renal function outcomes in patients treated with robot-assisted partial nephrectomy (RAPN) for renal cell carcinoma (RCC).

PATIENTS AND METHODS

Patients undergoing RAPN for clinically localized RCC between January 2014 and December 2019 at a tertiary robotic reference center were evaluated. Clinical course, pathologic characteristics, and long-term outcomes were obtained from our institutional review board-approved RCC database.

RESULTS

A total of 234 patients were available for analysis. Median follow-up was 46 months (10.8-97.8 months), with 77 patients (32.9%) having at least 5-years of follow-up. Pathology revealed clear-cell RCC in 67.5% (n = 158). Among unfavorable factors, nuclear grades 3 or 4 were found in 67 (29.4%), lymphovascular invasion in 10 (4.3%), positive surgical margins in 22 (9.4%), necrosis in 21 (9%), and sarcomatoid pattern in 2 patients (0.9%). At 12 months, mean serum creatinine was 1.04 mg/dL and 12.9% of patients experienced upstaging in chronic kidney disease. Overall recurrence-free survival at 5-years was 97.8%. There were five local (2.1%) and two distant (0.9%) recurrences, none of them resulting in cancer-specific death. Median time to recurrence was 20 months (11-64 months). Warm ischemia time [hazard ratio (HR) = 1.14, p = 0.034] and sarcomatoid pattern (HR = 124.57, p = 0.001) were the only variables associated with local relapse.

CONCLUSIONS

Data from this large cohort demonstrate that patients undergoing RAPN have a low incidence of local and distant relapse, resulting in excellent long-term survival while preserving stable renal function in most patients.

Partial and Radical Nephrectomy Provides Equivalent Oncologic Outcomes in pT3a Renal Cell Carcinoma: A Population-Based Study

Purpose

To compare the cause-specific survival (CSS) and overall survival (OS) of patients with localized T3a renal cell carcinoma (RCC) after partial nephrectomy (PN) or radical nephrectomy (RN).

Methods

We obtained the demographic and clinicopathological data of 7,127 patients with localized T3a RCC and who underwent PN or RN from the Surveillance, Epidemiology, and End Results (SEER) database. These patients were divided into fat invasion cohort and venous invasion cohort for subsequent analysis. Kaplan–Meier analysis (KMA) and univariate and multivariate Cox proportional hazards regression analyses were used to evaluate the effects of PN or RN on OS and CSS. Meanwhile, 65 cases with clinical T1 (cT1) RCC upstaged to pathological T3a (pT3a) who were treated in Tongji Hospital (TJH) from 2011 to 2020 and underwent PN or RN were identified.

Results

In the study cohort, 2,085 (29.3%) patients died during the 1–172 months’ follow-up, of whom 1,155 (16.2%) died of RCC. In the two cohorts of fat invasion and venous invasion, KMA indicated that the PN group had favorable survival (p < 0.001). However, after propensity score matching (PSM), univariate and multivariate Cox regression analyses showed that the PN and RN groups had comparable CSS in the fat invasion cohort (p = 0.075) and the venous invasion cohort (p = 0.190). During 1–104 months of follow-up, 9 cases in the Tongji cohort had disease recurrence. There was no significant difference in recurrence-free survival between the RN group and the PN group (p = 0.170).

Conclusions

Our analysis showed that after balancing these factors, patients with localized pT3a RCC receiving PN or RN can achieve comparable oncologic outcomes. PN is safe for selected T3a patients.

Is Preoperative Magnetic Resonance Imaging in a Daily Clinical Setting Useful to Evaluate Tumor Invasion Beyond the Pseudocapsule in Renal Cell Carcinoma?

Background

We wanted to clarify whether preoperative magnetic resonance imaging (MRI) in the clinical setting can evaluate the pathologic pseudocapsule (PC) morphology with high accuracy in renal cell carcinoma (RCC).

Methods

We retrospectively analyzed 34 consecutive patients who underwent MRI (1.5 or 3.0T, 5 mm slices) prior to partial nephrectomy (PN) for RCC at our institution between January 2010 and December 2019. First, the correlation between PC morphology (complete or incomplete) and tumor infiltration to the renal parenchyma was examined as pathologic validation. Second, the concordance rate of PC morphology between pathologic tissue and preoperative MRI was evaluated as radiologic validation. Third, risk factor for renal parenchymal invasion in RCC was analyzed.

Results

In the pathologic validation, parenchymal invasion rates were 11% and 28% in the "complete PC" and "incomplete PC" groups, respectively. In the radiologic validation, pathological PC morphology could be diagnosed on preoperative MRI in 17 patients (50.0%). "None PC" on MRI had the lowest positive predictive value (PPV) (0%), "partial PC" on MRI had a good PPV (76.5%), "complete PC" on MRI had a relatively low PPV (33.3%). Unfortunately, these data were insufficient for diagnostic accuracy. As risk factor for renal parenchymal invasion in RCC, only pathologic subtype (non-clear cell) was found to have significant differences in the multivariate analysis.

Conclusion

The results of this study suggest that renal tumors with pathologically incomplete PC have a high possibility of renal parenchymal invasion. However, it is currently difficult to accurately evaluate pathologic PC morphology by preoperative MRI in the clinical setting.

Histopathological validation of safe margin for nephron-sparing surgery based on individual tumor growth pattern

Background

To evaluate the clinicopathologic value of morphological growth patterns of small renal cell carcinoma (sRCC) and determine the actual demand for taking a rim of healthy parenchyma to avoid positive SM.

Methods

Data was collected from 560 sRCC patients who underwent laparoscopic surgeries from May 2010 to October 2017. One hundred forty-nine cases received nephron-sparing surgery (NSS) and others received radical nephrectomy (RN). All specimens were analyzed separately by two uropathologists, and three morphological growth patterns were identified. The presence of pseudocapsule (PC), surgical margins (SM), and other routine variables were recorded. The relationship between growth patterns and included variables was measured by the χ² test and Fisher’s exact probability test. Survival outcomes were evaluated by Kaplan-Meier method and the log-rank test.

Results

The median age of patients was 63.2 years old and the mean tumor diameter was 3.0 cm. Four hundred eighty (85.7%) cases were clear cell RCC and 541 (96.6%) cases were at the pT1a stage. Peritumoral PC was detected in 512 (92.5%) specimens, and the ratio of tumor invasion in PC in infiltration pattern increased obviously than that of the other growth patterns. Similarly, the pT stage was significantly correlated with the infiltration pattern as well. One hundred forty-nine patients underwent NSS and 3 (2.0%) of them showed positive SM after operation. Statistical differences of the 5-year overall survival (OS) and the cancer-specific survival (CSS) existed between different morphological growth patterns, PC status, and pT stages.

Conclusions

Morphological growth patterns of sRCC might be used as a potential biomarker to help operate NSS to avoid the risk of positive SM. How to distinguish different morphological growth patterns before operation and the effectiveness of the growth pattern as a novel proposed parameter to direct NSS in sRCC patients deserves further exploration.

Impact of margin status on survival after radical nephrectomy for renal cell carcinoma

BACKGROUND

Data about the impact of surgical margin positivity on patient outcomes following radical nephrectomy (RN) for renal cell carcinoma (RCC) is limited. We evaluate the effect of positive surgical margins (PSMs) on relapse-free survival (RFS) and overall survival (OS.) METHODS: Clinicopathologic data of patients who underwent RN for RCC was analyzed based on margin status. χ² and Student t test were used to compare groups. Cox regression analysis was used for the analysis. Kaplan-Meier method was used for survival curves.

RESULTS

A total of 485 patients who underwent RN for RCC were analyzed. Most patients with T1/T2 stage had NSM. Most patients with T4 had PSM. T3 patients were split between the two groups. Analysis of the T3 group showed shorter RFS in the PSM group at 3 years (hazard ratio [HR]: 4.3, p = .01), and 5 years (HR: 4.3, p = .01.) OS analysis showed worse OS in PSM but not statistically significant. There was a significant association between PSM and laterality (p = .023) and histologic type (p = .025.) CONCLUSIONS: PSM was associated with shorter RFS after RN in T3 RCC patients. There was a trend towards worse OS in the PSM group, but it did not reach statistical significance. Laterality and histologic type were associated with surgical margin status.

Robotic-assisted partial nephrectomy (RAPN) and standardization of outcome reporting: a prospective, observational study on reaching the "Trifecta and Pentafecta"

Partial nephrectomy (PN) for small renal masses is common, but outcomes are not reported in a standard manner. Traditionally, parameters such as 90-day mortality, blood loss, transfusion rates, length of stay, nephrometry scoring and complications are published but their collective impact on warm ischemia time (WIT) and post-surgery GFR is rarely determined. Thus, our aim was to assess if “Trifecta” and “Pentafecta” outcomes could be used as useful surgical outcome markers. A prospective database of 252 Robotic-Assisted PN (RAPN) cases (2008–2019) was analysed. “Pentafecta” was defined as achievement of “Trifecta” (negative surgical margin, no postoperative complications and WIT of < 25 min) plus over 90% estimated GFR preservation and no CKD stage upgrading at 1 year. Binary logistic regression analysis was conducted to predict factors which may prevent achieving a Trifecta/Pentafecta. Median tumour size was 3 cm and mean WIT was 15 min. Positive surgical margins (PSM) occurred in 2 cases. Overall, the intra-operative complication rate was 7%. One recurrence conferred 5-year cancer-free survival of 97%. Trifecta outcome was achieved in 169 (67%) and Pentafecta in 141 (56%) of cases. At logistic regression analysis, intraoperative blood loss was the only factor to affect Trifecta achievement (p = 0.018). Advanced patient age negatively impacted Pentafecta achievement (p = 0.010). The Trifecta and Pentafecta outcomes are easily applicable to PN data, and offer an internationally comparable PN outcome, quality measure. We recommend applying this standardization to national data collection to improve the quality of reporting and ease of interpretation of surgeon/centres’ outcomes.

Long-term oncologic outcomes of positive surgical margins following robot-assisted partial nephrectomy

Background

Previous reports on positive surgical margin (PSM) after robot-assisted partial nephrectomy (RAPN) have reached inconsistent conclusions as to the impact of a PSM on oncologic outcomes. We sought to determine the effect of PSM on long-term cancer recurrence and survival outcomes.

Methods

We queried our renal oncology database for patients having undergone RAPN and compared recurrence-free survival (RFS) and overall survival (OS) between patients with PSM and negative surgical margin (NSM). Kaplan-Meier analysis was also performed for RFS and OS for PSM versus NSM.

Results

Of the 432 patients who underwent RAPN we identified 29 (6.7%) patients with PSM and 403 (93.3%) patients with NSM. Median follow-up for the overall cohort was 45.1 months. Three of the 29 patients with PSM and fourteen of the 403 patients with NSM had disease recurrence (P=0.09). RFS at 24, 48, and 72 months was 95.8%, 90%, and 85.5% for patients with NSM and 96.6%, 86.6%, and 80.4% for patients with PSM, respectively (log-rank P value =0.382). OS at 24, 48, and 72 months was 98%, 93.1%, and 89.7% for patients with NSM and 96.3%, 91.2%, and 85.2% for patients with PSM, respectively (log-rank P value =0.584).

Conclusions

While PSM are relatively uncommon, their presence still serves as a potential risk factor for worse oncologic outcomes. In instances of PSM, immediate secondary intervention is most likely unnecessary and more attentive long-term clinical follow-up, especially in patients with high-risk features, may be more advisable.

Survival Analysis of Pathological T3a Upstaging in Clinical T1 Renal Cell Carcinoma

AIM

To evaluate the oncological outcomes of pathological T3a upstaging from clinical T1 renal cell carcinoma.

PATIENTS AND METHODS

We retrospectively studied patients who underwent radical or partial nephrectomy for clinical T1 renal tumors.

RESULTS

The median follow-up period was 44 months. At three and five years, the respective overall survival rate was 88.7% and 82.4% in pT3a disease, 95.7% and 93.4% in pT1 (p=0.008), the cancer-specific survival rate, 93.9% and 90.8% in pT3a, 99% and 97.7% in pT1 (p=0.001), and the recurrence-free survival rate, 79.7% and 71.0% in pT3a, and 95.5 and 94.3% in pT1 (p<0.001).

CONCLUSION

Patients with pathological T3a upstaging tumors were associated with a significantly decreased survival rate, along with a higher recurrence rate when compared to those with pathological T1 disease.

Renal volume matters: Assessing the association between excisional volume loss and renal function after partial nephrectomy

BACKGROUND/OBJECTIVES

To investigate the oncological and functional outcomes after partial nephrectomy for clinical stage T1 (cT1) renal cell carcinoma (RCC), and assess the association between excisional volume loss (EVL) and postoperative renal function.

METHODS

We retrospectively reviewed 150 patients with cT1 RCC undergoing partial nephrectomy from 2002 to 2016. End-point evaluation was assessed by recurrence free survival (RFS), overall survival (OS), stage III and stage IV chronic kidney disease (CKD). Regression models were used to determine the risk factors of CKD after surgery. The relationship between EVL and renal function decline was evaluated using Spearman correlation method.

RESULTS

Ninety patients with clinical stage T1a (cT1a) tumors and 60 patients with clinical stage T1b (cT1b) tumors were included. There were no differences in RFS, OS, and risk of stage III and stage IV CKD between the two groups. In Cox regression models, multivariate analysis showed that preoperative estimated glomerular filtration rate (eGFR) was an independent risk factor for developing stage III (hazard ratio 0.937, P < 0.001) and stage IV CKD (hazard ratio 0.929, P = 0.027). EVL was significantly associated with postoperative eGFR decrease. (Correlation Coefficient = 0.325, P = 0.003).

CONCLUSIONS

Patients with cT1a and cT1b RCC have comparable oncological and functional outcome after partial nephrectomy, and preoperative eGFR is an independent factor to predict developing CKD. EVL has influence on the postoperative renal function decline.

The Correlation of Clinicopathological Features With the Status of Surgical Margins in Renal Cell Cancer Patients Following Nephron-Sparing Surgery: A Systematic Review and Meta-Analysis

Objectives: The aim of this study was to evaluate the correlation of various clinicopathological variables with positive surgical margins (PSMs) in renal cell cancer (RCC) patients after nephron-sparing surgery (NSS). Methods: A systematic search of PubMed, EMBASE, Web of Science, and China National Knowledge Infrastructure (CNKI) was performed to identify studies that compared PSMs with negative surgical margins (NSMs) and were published up to December 2018. Outcomes of interest included perioperative and postoperative variables, and the data were pooled by odds ratios (ORs)/standard mean differences (SMD) with 95% confidence intervals (CIs) to evaluate the strength of such associations. STATA 12.0 software was used for all statistical analyses. Results: Based on the inclusion and exclusion criteria, 13 studies including 47,499 patients with RCC were analyzed. The results showed that higher Furhman grade (pooled OR = 1.25; 95% CI: 1.14-1.37; P < 0.001), higher pathological stage (pooled OR = 2.67; 95% CI: 2.05-3.50; P < 0.001), non-clear cell RCC (non-ccRCC) histology (pooled OR = 0.78; 95% CI: 0.72-0.84; P < 0.001), and non-white race (pooled OR = 0.90; 95% CI: 0.82-0.99; P = 0.026) were significantly associated with high risk of PSMs. However, age (pooled SMD = 0.09; 95% CI: -0.01-0.20; P = 0.078), gender (female vs. male) (pooled OR = 1.04; 95% CI: 0.96-1.12; P = 0.377), tumor laterality (left vs. right) (pooled OR = 1.09; 95% CI: 0.84-1.42; P = 0.501), tumor focality (unifocal vs. multifocal) (pooled OR = 0.67; 95% CI: 0.23-1.90; P = 0.445), tumor size (pooled SMD = 0.03; 95% CI: -0.10-0.15; P = 0.685), and surgical approach (open vs. non-open) (pooled OR = 0.94; 95% CI: 0.62-1.42; P = 0.763) had no relationship with PSMs. Sensitivity analysis showed that all models were stable, and no publication bias was observed in our study. Conclusions: The present findings demonstrate that the presence of PSMs was associated with higher Furhman grade and higher pathological stage. Additionally, non-white patients with non-ccRCC histology had a high risk of PSMs after NSS. Further multicenter and long-term follow-up studies are required to verify these findings.

Low Rate of Cancer Events After Partial Nephrectomy for Renal Cell Carcinoma: Clinicopathologic Analysis of 1994 Cases with Emphasis on Definition of "Recurrence"

BACKGROUND

Systematic pathology reviews in patients who experienced a clinical "recurrence" after partial nephrectomy for renal cell carcinoma (RCC) are anecdotal; therefore, definitions of "recurrence" varies considerably. We aimed to better define local recurrence by re-evaluation of surgical specimens of patients who experienced "recurrences" after partial nephrectomy at our institution.

MATERIALS AND METHODS

Retrospective analysis of our institutional partial nephrectomy data set was performed. Patients who were clinically diagnosed with a local recurrence during the oncological follow-up after primary intervention for RCC were considered (January 2007 to December 2017, institutional review board number 5065, 15-1593). Re-evaluation of specimens coming from either primary treatment or management of the diagnosed recurrent disease was performed by 2 dedicated urologic pathologists. According to the findings of the pathology review, patients were assigned to 3 groups of disease event: (1) local recurrence of RCC; (2) new occurrence of RCC; and (3) micrometastatic RCC. Patient demographic characteristics, tumor pathological characteristics, oncological outcomes, disease treatment, and follow-up were reported for each patient. Cancer-specific survival was compared using the Kaplan-Meier method.

RESULTS

Of 1994 cases recorded in the institutional database, data on 30 patients who were clinically diagnosed with a local recurrence were extracted. After pathology review, 9 patients were found who truly developed a local recurrence (group 1). Positive surgical margin status was poorly related to the likelihood of a true local recurrence as defined herein. Twelve patients were assessed with a new occurrence of RCC (group 2). Nine were diagnosed with micrometastatic RCC (group 3). With comparable follow-up lengths among the groups (39 [interquartile range (IQR), 32-45] versus 51.5 [IQR, 35-90.5] versus 42 [IQR, 13-65], group 1 versus 2 versus 3, respectively; P = .4), patients classified in group 1 and 3 had comparable cancer-specific survival (P = .5). Conversely, patients in group 2 were less likely to die of disease compared with group 1 and 3 patients (P = .02).

CONCLUSION

Careful pathologic classification of RCC disease events after partial nephrectomy has important prognostic implications and allows more precise study of the clinical significance of margin status.

Peri-operative and local control outcomes of robot-assisted partial nephrectomy vs percutaneous cryoablation for renal masses: comparison after matching on radiological stage and renal score

OBJECTIVES

To compare the oncological outcomes of percutaneous cryoablation (PCA) vs robot-assisted partial nephrectomy (RAPN) for the treatment of T1 renal tumours.

PATIENTS AND METHODS

We conducted a retrospective study in all patients treated by RAPN or PCA for malignant renal tumours in one of four centres between 2009 and 2016. Tumours were paired one by one using radiological tumour stage and RENAL nephrometry score (package matchit, R software version 3.2.2). Malignancy was confirmed by biopsy for all patients in the PCA group. Patient characteristics before and after matching and oncological results were compared between the two groups. Cox regression, adjusted for age, treatment type, histological type and margins, was used to identify factors associated with time to local recurrence. Positive margins were defined histologically in the RAPN group and radiologically in the PCA group.

RESULTS

A total of 647 patients were identified; 470 underwent RAPN and 177 underwent PCA. After matching, there was no significant difference between the two groups (RAPN, n = 177; PCA, n = 177) with regard to tumour stage, RENAL nephrometry score, tumour size (27.6 vs 25.9 mm; P = 0.07) and gender ratio. Patients in the PCA group remained significantly older (69.9 vs 59.8 years; P < 0.001). The absolute recurrence rate was 2.8% in the RAPN group vs 8.4% in the PCA group (P = 0.03). The 5-year recurrence-free survival rate was 85% in the PCA group vs 95% in the RAPN group (log-rank P = 0.02). In multivariate analysis, the presence of positive margins and the type of treatment were the two factors significantly associated with local recurrence (P < 0.001 and P = 0.046, respectively).

CONCLUSION

The local recurrence rate after PCA was significantly higher than after RAPN for T1 renal tumours. Incomplete treatment was the main criterion associated with recurrence. The recurrence rate may have been overestimated in the PCA group because of closer radiological follow-up in these patients.

Histopathologic analysis of stage pT1b kidney neoplasms for optimal surgical margins of nephron-sparing surgery

Objective

To evaluate the pathological features and define the optimal surgical margins (SM) of nephron-sparing surgery (NSS) for kidney neoplasms 4–7 cm (stage pT1b) on preoperative imaging.

Materials and methods

The retrospective study included 748 patients who were diagnosed stage pT1b renal tumors and underwent either radical nephrectomy (RN, n = 475) or NSS (n = 273) from January 2004 to March 2017. The tumor size, pathological subtype, Fuhrman grade, status of peritumoral pseudocapsule (PC) and tumor multifocality were recorded. The relationship between peritumoral PC and positive SM was calculated statistically by Fisher’s exact probability test.

Results

The mean tumor diameter was 5.4 cm (range: 4.1–7.0 cm), 65 (8.7%) cases were discovered with multifocal lesions and 686 (91.7%) were surrounded with peritumoral PC in all 748 specimens. 57 (8.3%) of 686 cases were proved with tumor infiltrated beyond PC [infiltration (+)], and the presence of PC infiltration (+) was significantly correlated with positive SM (p = 0.016). The infiltrative depth of tumor cells into renal parenchyma beyond PC was all limited in 3 mm and the proportion of ≤ 1, 1–2 and 2–3 mm was 21.1% (12/57), 59.6% (34/57) and 19.3% (11/57), respectively.

Conclusions

Our report indicates a 3 mm excisional margin is acceptable to ensure negative SM when operating NSS on stage pT1b kidney neoplasms.

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.

Recurrence in Localized Renal Cell Carcinoma: a Systematic Review of Contemporary Data

PURPOSE OF REVIEW

Patients with localized renal cell carcinoma (RCC) are at risk of recurrence. The purpose of this review was to characterize the literature on recurrence rates and risk factors after diagnosis of localized RCC.

RECENT FINDINGS

Our search revealed that existing data examining the prevalence of recurrence rates predominantly originates from cohorts of patients diagnosed and treated in the 1980s to 1990s, and may therefore not be as useful for counseling for current patients today. Many nomograms including the Cindolo Recurrence Risk Formula, the University of California-Los Angeles (UCLA) Integrated Scoring System (UISS), the SSIGN score, the Kattan nomogram, and the Karakiewicz nomogram have shown value in identifying patients at higher risk for recurrence. Biomarkers and gene assays have shown promise in augmenting the predictive accuracy of some of the aforementioned predictive models, especially when multiple gene markers are used in combination. However, more work is needed in not only developing a model but also validating it in other settings prior to clinical use. Adjuvant therapy is a promising new treatment strategy for patients with high-risk disease. Importantly, too many surveillance strategies exist. This may stem from the lack of a consensus in the urological community in how to follow these patients, as well as the variable guideline recommendations. In conclusion, contemporary recurrence rates are needed. Recurrence risk prediction models should be developed based on a series of more contemporary patients, and externally validated prior to routine clinical practice. Surveillance strategies following treatment of localized RCC need to be identified and standardized. Finally, there is a trend toward personalizing surveillance regimens to more appropriately screen patients at higher risk of recurrence.