Reassessing the Current TNM Lymph Node Staging for Renal Cell Carcinoma

Treatment Landscape of Renal Cell Carcinoma

OPINION STATEMENT

The treatment landscape of renal cell carcinoma (RCC) has evolved significantly over the past three decades. Active surveillance and tumor ablation are alternatives to extirpative therapy in appropriately selected patients. Stereotactic body radiation therapy (SBRT) is an emerging noninvasive alternative to treat primary RCC tumors. The advent of immune checkpoint inhibitors (ICIs) has greatly improved the overall survival of advanced RCC, and now the ICI-based doublet (dual ICI-ICI doublet; or ICI in combination with a vascular endothelial growth factor tyrosine kinase inhibitor, ICI-TKI doublet) has become the standard frontline therapy. Based on unprecedented outcomes in the metastatic with ICIs, they are also being explored in the neoadjuvant and adjuvant setting for patients with high-risk disease. Adjuvant pembrolizumab has proven efficacy to reduce the risk of RCC recurrence after nephrectomy. Historically considered a radioresistant tumor, SBRT occupies an expanding role to treat RCC with oligometastasis or oligoprogression in combination with systemic therapy. Furthermore, SBRT is being investigated in combination with ICI-doublet in the advanced disease setting. Lastly, given the treatment paradigm is shifting to adopt ICIs at earlier disease course, the prospective studies guiding treatment sequencing in the post-ICI setting is maturing. The effort is ongoing in search of predictive biomarkers to guide optimal treatment option in RCC.

Adjuvant Therapy in Renal Cell Carcinoma: Are we ready for prime time?

The standard of care for localized renal cell carcinoma (RCC) is radical or partial nephrectomy. Despite complete resection, a subset of patients will develop locoregional recurrence or metastatic disease. Adjuvant immunotherapy has been studied since the 1980 s as the primary method to mitigate tumor recurrence after definitive surgery. We herein discuss published and ongoing clinical trials investigating adjuvant therapy in localized or locoregional RCC.

A Nomogram Predicting the Prognosis of Renal Cell Carcinoma Patients with Lung Metastases

BACKGROUND

The optimal tool for predicting the survival of renal cell carcinoma (RCC) patients with lung metastases remains controversial.

METHODS

We selected patients diagnosed with RCC and lung metastases, from 2010 to 2015, from the Surveillance, Epidemiology, and End Results (SEER) database. After the selection of inclusion criteria and exclusion criterion, the rest of the patients were incorporated into model analysis. Least absolute shrinkage and selection operator (LASSO) regression was used to select the most important features for construction of a nomogram predicting cancer-specific survival. A calibration plot and the concordance index (C-index) were used to estimate nomogram efficacy in a validation cohort. The association between important factors selected by LASSO regression, and prognosis was assessed by the Kaplan-Meier (KM) survival curve. The receiver operating characteristic (ROC) curves were drawn to compare sensitivity and specificity between the nomogram we built and the TNM stage-based model.

RESULTS

A total of 1,369 patients met the inclusion criteria, but not the exclusion criteria. The LASSO regression model reduced 15 features to seven potential predictors of survival, including tumor grade, the extent of surgery, N and T status, histological profile, and brain and bone metastasis status. Such features had good discrimination in the KM survival curves. The nomogram showed excellent discriminatory power (C-index, 0.71; 95% confidence interval: 0.70 to 0.72) and good calibration in terms of both 1- and 2-year cancer-specific survival. The nomogram showed great discriminatory power (C-index 0.68) and adequate calibration when applied to the validation cohort. The areas under the curve (AUCs) of nomogram were 0.767 and 0.780, respectively, and the AUCs of TNM stage were 0.617 and 0.618 at 1 and 2 years, respectively.

CONCLUSIONS

Our nomogram might play a major role in predicting the cancer-specific survival of RCC patients with lung metastases.

Outcome after resection of occult and non-occult lymph node metastases at the time of nephrectomy

PURPOSE

There is sparse evidence on outcomes of resected occult LN metastases at the time of nephrectomy (synchronous disease). We sought to analyse a large international cohort of patients and to identify clinico-pathological predictors of long-term survival.

MATERIALS AND METHODS

We collected data of consecutive patients who underwent nephrectomy and LND for T_any cN0-1pN1 and cM0-1 RCC at 7 referral centres between 1988 and 2019. Patients were stratified into four clinico-pathological groups: (1) cN0cM0-pN1, (2) cN1cM0-pN1(limited, 1-3 positive nodes), (3) cN1cM0-pN1(extensive, > 3 positive nodes), and (4) cM1-pN1. Overall survival (OS) was estimated using the Kaplan-Meier method, and associations with all-cause mortality (ACM) were evaluated using Cox models with multiple imputations.

RESULTS

Of the 4370 patients with LND, 292 patients with pN1 disease were analysed. Median follow-up was 62 months, during which 171 patients died. Median OS was 21 months (95% CI 17-30 months) and the 5-year OS rate was 24% (95% CI 18-31%). Patients with cN0cM0-pN1 disease had a median OS of 57 months and a 5-year OS rate of 43%. 5-year OS (median OS) decreased to 29% (33 months) in cN1cM0-pN1(limited) and to 23% (23 months) in cN1cM0-pN1(extensive) patients. Those with cM1-pN1 disease had the worst prognosis, with a 5-year OS rate of 13% (9 months). On multivariable analysis, age (p = 0.034), tumour size (p = 0.02), grade (p = 0.02) and clinico-pathological group (p < 0.05) were significant predictors of ACM.

CONCLUSION

Depending on clinico-pathological group, grade and tumour size, 5-year survival of patients with LN metastases varies from 13 to 43%. Patients with resected occult lymph node involvement (cN0/pN1 cM0) have the best prognosis with a considerable chance of long-term survival.

Prognostic significance of pathologic nodal positivity in non-metastatic patients with renal cell carcinoma who underwent radical or partial nephrectomy

This retrospective, five-multicenter study was aimed to evaluate the prognostic impact of pathologic nodal positivity on recurrence-free (RFS), metastasis-free (MFS), overall (OS), and cancer-specific (CSS) survivals in patients with non-metastatic renal cell carcinoma (nmRCC) who underwent either radical or partial nephrectomy with/without LN dissection. A total of 4236 nmRCC patients was enrolled between 2000 and 2012, and followed up through the end of 2017. Survival measures were compared between 52 (1.2%) stage pT1-4N1 (LN+) patients and 4184 (98.8%) stage pT1-4N0 (LN-) patients using Kaplan-Meier analysis with the log-rank test and Cox regression analysis to determine the prognostic risk factors for each survival measure. During the median 43.8-month follow-up, 410 (9.7%) recurrences, 141 (3.3%) metastases, and 351 (8.3%) deaths, including 212 (5.0%) cancer-specific deaths, were reported. The risk factor analyses showed that predictive factors for RFS, CSS, and OS were similar, whereas those of MFS were not. After adjusting for significant clinical factors affecting survival outcomes considering the hazard ratios (HR) of each group, the LN+ group, even those with low pT stage, had similar to or worse survival outcomes than the pT3N0 (LN-) group in multivariable analysis and had significantly more relationship with RFS than MFS. All survival measures were significantly worse in pT1-2N1 patients (MFS/RFS/OS/CSS; HR 4.12/HR 3.19/HR 4.41/HR 7.22) than in pT3-4N0 patients (HR 3.08/HR 2.92/HR 2.09/HR 3.73). Therefore, LN+ had an impact on survival outcomes worse than pT3-4N0 and significantly affected local recurrence rather than distant metastasis compared to LN- in nmRCC after radical or partial nephrectomy.

Reassessment of American Joint Committee on Cancer Staging for Stage III Renal Cell Carcinoma With Nodal Involvement: Propensity Score Matched Analyses of a Large Population-Based Study

Background: To assess the role of nodal involvement in stage III renal cell carcinoma (RCC) according to the American Joint Committee on Cancer (AJCC) 8th staging system. We compared the survival outcomes of RCC patients with pT1-3N1M0 disease and those with pT3N0M0 or stage IV (stratified as pT4NanyM0 and pTanyNanyM1) disease in a large population-based cohort. Methods: A cohort of 3,112 eligible patients with RCC was identified from the Surveillance, Epidemiology, and End Results (SEER) database, registered between January 2004 and December 2015. Kaplan-Meier and Cox proportional hazards models were used to evaluate the overall survival (OS), and cancer-specific survival (CSS). The prognostic value of the modified stage for pT1-3N1M0 disease was assessed by nomogram-based analyses. Propensity score matching (PSM) was used to adjust for potential baseline confounding. Results: Patients with pT1-3N1M0 disease showed similar survival outcomes (median OS 41.0 vs. 38.0 months, P = 0.77; CSS 45.0 vs. 39.0 months, P = 0.59) to pT4NanyM0 patients, whereas the significantly better survival outcome was found for pT3N0M0 patients. After PSM, comparable survival rates were observed between pT1-3N1M0 group and pT4NanyM0 group, which were still significantly worse than the survival of pT3N0M0 patients. The modified stage IIIA (pT3N0M0), IIIB (pT1-3N1M0, pT4NanyM0), and IV (pTanyNanyM1) showed higher predictive accuracy than AJCC stage system in the nomogram-based analyses (concordance index: 0.70 vs. 0.68, P < 0.001 for OS; 0.71 vs. 0.69, P < 0.001 for CSS). Conclusions: The pT1-3N1M0 RCC might be reclassified as stage IIIB together with pT4NanyM0 disease for better prediction of prognosis, further examination and validation are warranted.

The prognostic significance of nodal disease burden in patients with lymph node metastases from renal cell carcinoma

OBJECTIVES

To assess the relationship between nodal disease burden and overall survival (OS) among patients with lymph node (LN) metastases from renal cell carcinoma (RCC) METHODS: The National Cancer Data Base was used to identify 2,975 patients with RCC who were treated with radical nephrectomy and were found to have regional LN metastases. Associations between the number of positive and negative LN removed and OS were assessed using Cox proportional hazards regression. The median follow-up time among survivors was 3.6years.

RESULTS

The median number of positive LN was 1 (interquartile range 1-3). A higher number of positive LN was associated with higher all-cause mortality on multivariable analysis (HR 1.06 per 1 positive LN, 95% CI 1.04, 1.07, P < 0.001). Conversely, higher negative LN counts were associated with better OS (HR 0.97 per 1 negative LN, 95% CI 0.96, 0.99, P < 0.001). The adjusted probability of a patient with 1 LN removed that was positive surviving at least 2 years was 56%, a figure that increased to 64% when 1 out of 10 LN removed was positive and decreased to 38% when 10 out of 10 LN removed were positive.

CONCLUSIONS

Ours is the first study to show that differences in nodal disease burden translate into clinically significant differences in survival among patients with LN metastases from RCC.

Templates of Lymph Node Dissection for Renal Cell Carcinoma: A Systematic Review of the Literature

Background: The role of lymph node dissection (LND) for renal cell carcinoma (RCC) is controversial. Notably, the conflicting evidence on the benefits and harms of LND is inherently linked to the lack of consensus on both anatomic templates and extent of lymphadenectomy. Herein, we provide a detailed overview of the most commonly dissected templates of LND for RCC, focusing on key anatomic landmarks and patterns of lymphatic drainage.

Methods: A systematic review of the English-language literature was performed without time filters in July 2018 in accordance to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement recommendations. The primary endpoint was to summarize the most commonly dissected templates of LND according to the side of RCC.

Results: Overall, 25 studies were selected for qualitative analysis. Of these, most were retrospective. The LND template was heterogeneous across studies. Indications and extent of LND were either not reported or not standardized in most series. The most commonly dissected template for right-sided tumors included hilar, paracaval, and precaval nodes, with few authors extending the dissection to the inter-aortocaval, retrocaval, common iliac or pre/paraaortic nodes. Similarly, the most commonly dissected template for left-sided tumors encompassed the renal hilar, preaortic and paraaortic nodes, with few authors reporting a systematic dissection of inter-aortocaval, retro-aortic, common iliac, or para-caval nodes.

Conclusions: In light of the unpredictable renal lymphatic anatomy and the evidence from available prospective mapping studies, the extent of the most commonly dissected templates might be insufficient to catch the overall anatomic pattern of lymphatic drainage from RCC.

Prognostic nomograms based on log odds of positive lymph nodes for patients with renal cell carcinoma: A retrospective cohort study

OBJECTIVES

The aim of the current study is to build prognostic nomograms for patients with renal cell carcinoma (RCC) and compare the predictive performance with the American Joint Committee on Cancer (AJCC) staging system.

METHODS

A total of 9453 patients were identified (2005-2015) from the Surveillance Epidemiology and End Results (SEER) database. Propensity-score matching (PSM) was conducted to reduce selective bias. The matched cohort was further divided equally into the development and the validation cohort. Nomograms based on log odds of positive lymph nodes (LODDS) were formulated to predict individualized cancer-specific survival (CSS) and overall survival (OS) for RCC. Then, the performance of nomograms was internally and externally validated via the concordance index (C-index) and calibration plots. Decision curve analysis (DCA) was used to compare the clinical practicable between nomograms and AJCC staging system.

RESULTS

LODDS was identified as an independent prognostic indicator for CSS and OS using univariate and multivariate Cox regression analyses. Two nomograms incorporating LODDS were formulated. The C-indices of the nomograms for predicting CSS and OS were 0.7561 (95% CI, 0.7356-0.7766) and 0.7140 (95% CI, 0.6936-0.7343) in the development cohort, which was higher than C-index of the AJCC staging system. The results were reproducible in the validation cohort. Moreover, internal and external calibration plots showed that the nomograms-predicted was consistent with the actual observation. Additionally, DCA demonstrated that the nomograms were superior to the AJCC staging system with obtaining more clinical net benefit.

CONCLUSIONS

LODDS could be considered as a reliable prognostic factor for patients with RCC. Two nomograms were able to more accurately and applicable than the AJCC staging system for predicting CSS and OS.

RETRACTED: Recommandations françaises du Comité de Cancérologie de l’AFU – Actualisation 2018–2020 : prise en charge du cancer du reinFrench ccAFU guidelines – Update 2018–2020: Management of kidney cancer

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). Cet article est retiré de la publication à la demande des auteurs car ils ont apporté des modifications significatives sur des points scientifiques après la publication de la première version des recommandations. Le nouvel article est disponible à cette adresse: DOI:10.1016/j.purol.2019.01.004. C’est cette nouvelle version qui doit être utilisée pour citer l’article. This article has been retracted at the request of the authors, as it is not based on the definitive version of the text because some scientific data has been corrected since the first issue was published. The replacement has been published at the DOI:10.1016/j.purol.2019.01.004. That newer version of the text should be used when citing the article.

Patterns of lymph node sampling and the impact of lymph node density in favorable histology Wilms tumor: An analysis of the national cancer database

INTRODUCTION

There is controversy about the role of lymph node (LN) sampling or dissection in the management of favorable histology (FH) Wilms tumor (WT), specifically how it performed and how it may impact survival.

OBJECTIVE

The objective of this study was to analyze factors affecting LN sampling patterns and the impact of LN yield and density (number of positive LNs/LNs examined) on overall survival (OS) in patients with advanced-stage favorable histology Wilms tumor (FHWT).

METHODS

The National Cancer Database (NCDB) was queried for patients with FHWT during 2004-2013. Demographic, clinical and OS data were abstracted for those who underwent surgical resection. Poisson regression was performed to analyze how factors influenced LN yield. Patients with positive LNs had LN density calculated and were further analyzed.

RESULTS

A total of 2340 patients met criteria, with a median age at diagnosis of 3 years (range 0-78 years). The median number of LNs examined was three (range 0-87). Lymph node yield was affected by age, race, insurance, tumor size, laterality, advanced stage, LN positivity, and institutional volume. A total of 390 (16.6%) patients had LN-positive disease. Median LN density for these LN-positive patients was 0.38 (range 0.02-1) (Summary Figure). Estimated 5-year OS was significantly improved for those with LN density ≤0.38 vs. >0.38 (94% vs. 84.6%, P = 0.012). In this population, on multivariate analysis, age and LN density were significant predictors of OS.

DISCUSSION

It is difficult to compile large numbers of cases in rare diseases like WT, and fortunately a large administrative database such as the NCDB can serve as a great resource. However, administrative data come with inherent limitations such as missing data and inability to account for a variety of factors that may influence LN yield and/or OS (specimen designation, pathologist experience, surgeon experience/volume, institutional Children's Oncology Group (COG) association, etc.). In this specific disease, the American Joint Committee on Cancer staging (captured by the NCDB) is different than the COG WT staging system that is used clinically, and the NCDB does not capture oncologic outcomes beyond OS.

CONCLUSIONS

In a review of the NCDB, various factors associated with LN yield and observed LN density were identified to be significantly associated with OS in patients with LN-positive FHWT. This reinforces the need for adequate LN sampling at the time of WT surgery, to maximize surgical disease control. It was proposed that LN density as a metric may allow for improved risk-stratification, and possibly allow for therapeutic reduction in a sub-set of patients with low LN density.

The role of lymph node dissection in the management of renal cell carcinoma: a systematic review and meta-analysis

Our objective was to evaluate the role of retroperitoneal lymph node dissection (LND) in non-metastatic (M0) and metastatic (M1) renal cell carcinoma (RCC). We searched Medline, EMBASE, Web of Science and Scopus from database inception to 29 August 2017 for studies of patients who underwent partial or radical nephrectomy for M0 or M1 RCC. Two investigators independently selected studies for inclusion. Risk of bias was assessed using the Newcastle-Ottawa scale, Cochrane Collaboration tool and National Heart, Lung and Blood Institute Quality Assessment Tool. Random effects meta-analysis was performed for all-cause-mortality. The GRADE approach was used to characterize quality of evidence. A total of 51 unique studies were included in the qualitative systematic review. Risk of bias was low in 41/51 (80%) studies. LND was not associated with all-cause mortality in either M0 (hazard ratio [HR] 1.02, 95% confidence interval [CI] 0.92-1.12; I² = 0%; four studies), M1 (HR 1.04, 95% CI 0.83-1.29; I² = 0%; two studies), or pooled M0 and M1 settings (HR 1.00, 95% CI 0.92-1.09; I² = 0%; seven studies), with no statistically significant differences according to M stage subgroups (P = 0.50). In the three studies that examined M0 subgroups with a high risk of nodal metastasis, LND was not associated with improved oncological outcomes. Studies on the association of extent of LND with survival reported inconsistent results. Meanwhile, a small proportion of patients with pN1M0 disease demonstrate durable long-term oncological control after surgery, with 10-year cancer-specific survival of 21-31%. Nodal involvement is independently associated with adverse prognosis in both M0 and M1 settings. GRADE quality of evidence was moderate or low for the outcomes examined. Although LND yields independent prognostic information, the existing literature does not support a therapeutic benefit to LND in either M0 or M1 RCC. High-risk M0 patient groups warrant further study, as a subset of patients with isolated nodal metastases experience long-term survival after surgical resection.

Notch 1 is a valuable therapeutic target against cell survival and proliferation in clear cell renal cell carcinoma

Notch 1 is a key component of the Notch pathway, which performs a crucial role in clear cell renal cell carcinoma (CCRCC) development. The present study aimed to investigate whether Notch 1 could serve as a potential target for CCRCC treatment. Firstly, an association analysis was performed using 52 CCRCC cases and 30 normal controls. The results indicated that Notch 1 protein expression in renal tissues was closely associated with the incidence of CCRCC. In addition, higher Notch 1 expression in CCRCC tissues was positively associated with higher tumor-node-metastasis stage and Fuhrman grade, in addition to larger tumor size. Subsequently, an in vitro study was conducted to examine the biological functions of Notch 1 in CCRCC 786-O cells through inhibiting the Notch 1 expression with Notch 1-specific small interfering RNA (siRNA). As a result, the inhibition of Notch 1 expression by increasing concentrations of Notch 1-specific siRNA dose-dependently decreased cell proliferation and increased cell apoptosis in 786-O cells. Furthermore, B-cell lymphoma-2 and procaspase-3 expression exhibited a dose-dependent decrease accompanied with a dose-dependent inactivation of the Akt/mammalian target of rapamycin (mTOR) signaling pathway in Notch 1 siRNA-treated 786-O cells. These findings demonstrated that Notch 1 was associated with CCRCC carcinogenesis and progression, the underlying mechanism of which was that Notch 1 acted as an activator for cell proliferation and a suppressor for cell apoptosis through the Akt/mTOR signaling-dependent pathway in CCRCC. In conclusion, the present study confirmed that Notch 1 is a valuable target against cell survival and proliferation in CCRCC treatment.

The lymph node pre-metastatic niche

Lymph node metastases occur frequently during the progression of many types of cancer, and their presence often reflects poor prognosis. The drainage of tumor-derived factors such as antigens, growth factors, cytokines, and exosomes through the lymphatic system to the regional lymph nodes plays an important role in the pre-metastatic conditioning of the microenvironment in lymph nodes, making them receptive and supportive metastatic niches for disseminating tumor cells. Modified immunological responses and remodeling of the vasculature are the most studied tumor-induced pre-metastatic changes in the lymph node microenvironment that promote metastasis, although other metastasis-relevant alterations are also starting to be studied. Here, I review our current understanding of the lymph node pre-metastatic niche, how tumors condition this niche, and the relevance of this conditioning for our understanding of the process of metastasis.

The role of lymphadenectomy in the management of renal cell carcinoma

The role of lymphadenectomy in the management of renal cell carcinoma has been established in staging but is less well defined as a therapeutic maneuver. Level one evidence suggests no survival benefit or increased complication rate with lymphadenectomy when performed concurrently with radical nephrectomy. However, several retrospective studies have identified a survival benefit when patients with increased risk of micrometastatic lymph node disease undergo lymphadenectomy. We perform a selective review of the literature and present the historical basis, risk assessment, use and development of nodal templates, and therapeutic benefits associated with the use of lymphadenectomy in the management of renal cell carcinoma.

The connectivity of lymphogenous and hematogenous tumor cell dissemination: biological insights and clinical implications

Although tumor cells are found in the blood early after tumorigenesis, dissemination through the lymphatic system and in particular the formation of lymph node metastases has long been considered to be a driving force behind the formation of secondary tumors in distant vital organs. Contemporary experimental observations and clinical trial results suggest that this may not be the case. In this review we survey the evidence for both points of view, and examine the hypothesis that the prognostic relevance of lymph node metastases may lie in their ability to indicate that primary tumors are producing soluble factors that have the potential to promote metastasis at these distant sites, for example by releasing tumor cells from dormancy. Furthermore, the interconnectivity between the lymphatic and blood circulatory systems underscores the relevance of the analysis of the properties of circulating and disseminated tumor cells for prognostic evaluation, patient stratification and understanding the biology of metastasis. We therefore give an overview of the current state of the art in this field.

The role of lymph node dissection in renal cell carcinoma

The role of lymph node dissection (LND) in the staging and treatment of renal cell carcinoma has long been a topic of debate. The controversy has focused on whether LND is purely an adjunctive staging procedure or has a therapeutic role in the management of this disease. Potential benefits include enhanced staging, better selection for adjuvant therapies/clinical trials, a decrease in recurrence rates, and improved disease-specific and overall survival. This article reviews the available literature on LND in renal cell carcinoma and discusses the potential benefits of aggressive surgical resection in select high-risk patients.

Node-positive renal cell carcinoma in the absence of distant metastases: predictors of cancer-specific mortality in a population-based cohort

Nodal metastases, even in the absence of distant metastases, portend a bad prognosis. The percentage of positive nodes (PPN) represents an important predictor of cancer-specific mortality (CSM) in patients in the group T(any) N(1) M(0) . In consequence, universal inclusion of PPN should be considered in prospective and retrospective CSM analyses.

OBJECTIVES

To examine the outcomes of patients with node-positive renal cell carcinoma (RCC) in the absence of distant metastases in a large population-based cohort of patients To examine the ability of standard risk factors to predict cancer-specific mortality (CSM).

PATIENTS AND METHODS

Using the Surveillance, Epidemiology, and End Results database, a total of 799 patients with RCC nodal metastases and absence of distant metastases undergoing nephrectomy were identified. Univariable and multivariable analyses was performed with the aim of identifying independent predictors of CSM in this cohort of patients. Specifically, we examined the effect of the number of removed nodes (NRN), the number of positive nodes (NPN) and the percentage of positive nodes (PPN) on CSM.

RESULTS

Actuarial survival estimates showed that 53.2, 37.8 and 25.7% of patients survived at 24, 60 and 120 months after nephrectomy. In Kaplan-Meier analyses, NRN failed to clearly discriminate between recorded CSM rates (log rank P = 0.07). Discrimination was noted when CSM was stratified according to NPN (log rank P = 0.02) and PPN (log rank P = 0.001). In multivariable analyses, age, Fuhrman grade, histological subtype, T stage and PPN were independent predictors of CSM.

CONCLUSIONS

Our data indicate that CSM of patients with exclusive nodal metastases differs according to PPN. Consequently, PPN warrants consideration in future prognostic schemes.

Sentinel node detection in renal cell carcinoma. A feasibility study for detection of tumour-draining lymph nodes

OBJECTIVE

To evaluate the feasibility of performing sentinel node detection in patients with renal cell carcinoma (RCC).

MATERIALS AND METHODS

An open series of 13 arbitrarily selected patients with T1b-T3b RCC scheduled for radical nephrectomy at a single Tertiary Academic Centre were examined with different modalities of sentinel node detection. Preoperative ultrasonography-guided injection of radioactive isotope, lymphoscintigram and single photon emission computed tomography/computed tomography, followed by intraoperative gamma-probe detection and Patent Blue detection, as well as postoperative scintigram of the main specimen were the planned interventions. These investigations were performed in conjunction with intended open radical nephrectomy.

RESULTS

In 10 of the 13 patients sentinel node detection was achieved with 32 sentinel nodes displayed. Radio-guided surgery using an intraoperative gamma-probe resulted in the highest realtive detection rate with detection of sentinel nodes in nine patients. In total, nine metastatic sentinel nodes were detected in three patients. One patient, preoperatively staged as N+, was restaged after sentinel node detection and histopathology as pN0.

CONCLUSIONS

Sentinel node detection in renal tumours is feasible although evaluation of different modes of detection needs further refinement and standardization. All nodes preoperatively detected by routine computed tomography as suspicious metastatic lesions were confirmed as sentinel nodes, including two nodes considered as metastatic by preoperative routine imaging but ultimately staged as non-metastatic sentinel nodes.

Validation of the 2009 TNM Classification for Renal Cell Carcinoma: Comparison with the 2002 TNM Classification by Concordance Index

PURPOSE

To assess the validity of the 2009 TNM classification for renal cell carcinoma (RCC) and compare its ability to predict survival relative to the 2002 classification.

MATERIALS AND METHODS

We identified 1,691 patients who underwent radical nephrectomy or partial nephrectomy for unilateral, sporadic RCC between 1989 and 2007. Cancer-specific survival was estimated by the Kaplan-Meier method and was compared among groups by the log-rank test. Associations of the 2002 and 2009 TNM classifications with death from RCC were evaluated by Cox proportional hazards regression models. The predictive abilities of the two classifications were compared by using Harrell's concordance (c) index.

RESULTS

There were 234 deaths from RCC a mean of 38 months after nephrectomy. According to the 2002 primary tumor classification, 5-year cancer-specific survival was 97.6% in T1a, 92.0% in T1b, 83.3% in T2, 61.9% in T3a, 51.1% in T3b, 40.0% in T3c, and 33.6% in T4 (p for trend<0.001). According to the 2009 classification, 5-year cancer-specific survival was 83.2% in T2a, 83.8% in T2b, 62.6% in T3a, 41.1% in T3b, 50.0% in T3c, and 26.1% in T4 (p for trend<0.001). The c index for the 2002 primary tumor classification was 0.810 in the univariate analysis and increased to 0.906 in the multivariate analysis. The c index for the 2009 primary tumor classification was 0.808 in the univariate analysis and increased to 0.904 in the multivariate analysis.

CONCLUSIONS

Our data suggest that the predictive ability the 2009 TNM classification is not superior to that of the 2002 classification.

Can a durable disease-free survival be achieved with surgical resection in patients with pathological node positive renal cell carcinoma?

PURPOSE

Patients with isolated regional nodal metastases from renal cell carcinoma are a distinct cohort for which resection of involved lymph nodes may be therapeutic. We assessed the outcomes of patients treated at our institution with pathological node positive renal cell carcinoma without concomitant metastatic disease (T(any)N+M0).

MATERIALS AND METHODS

A total of 2,521 patients with nonmetastatic renal cell carcinoma (T(any)N(any)M0) of any histological subtype treated with nephrectomy were identified between 1995 and 2009. Pathological regional node positive disease in the absence of clinically detectable metastases (T(any)N(1-2)M0) was present in 68 patients (2.7%) and these patients formed our study cohort. Patients were assessed for timing and location of recurrence, disease specific survival and overall survival. Multivariate Cox regression analysis was performed to define factors predictive of recurrence and overall survival.

RESULTS

Of the 68 patients with T(any)N(1-2)M0 renal cell carcinoma 22.1% were free of disease at a median followup of 43.5 months. In those patients experiencing recurrence, disease was detected within the first 4 months after surgery in 51% and was most commonly detected at multiple organ sites. The Kaplan-Meier estimated 5-year overall survival and disease specific survival was 37% and 39%, respectively. Predictors of a favorable outcome included an Eastern Cooperative Oncology Group performance status of 0, single node involvement, absence of sarcomatoid features and papillary histology.

CONCLUSIONS

Nephrectomy with lymph node dissection can provide a durable disease-free survival in a proportion of patients with regionally advanced renal cell carcinoma and limited lymph node metastases.

Staging of renal cell carcinoma: Current concepts

The most important and widely utilized system for providing prognostic information following surgical management for renal cell carcinoma (RCC) is currently the tumor, nodes, and metastasis (TNM) staging system. An accurate and clinically useful staging system is an essential tool used to provide patients with counseling regarding prognosis, select treatment modalities, and determining eligibility for clinical trials. Data published over the last few years has led to significant controversies as to whether further revisions are needed and whether improvements can be made with the introduction of new, more accurate predictive prognostic factors. Staging systems have also evolved with an increase in the understanding of RCC tumor biology. Molecular tumor biomarkers are expected to revolutionize the staging of RCC by providing more effective prognostic ability over traditional clinical variables alone. This review will examine the components of the TNM staging system, current staging modalities including comprehensive integrated staging systems, and predictive nomograms, and introduce the concept of molecular staging for RCC.

The current role of lymph node dissection in the management of renal cell carcinoma

The role of lymph node dissection remains controversial in the surgical management of renal cell carcinoma. Incidental renal masses are being diagnosed at increasing rates due to the routine use of CT scans. Despite the increase in incidental diagnosis of renal masses, 20% to 30% of patients present with metastatic disease. Currently, surgeons do not routinely perform lymph node dissection unless there is gross evidence of lymphadenopathy, as patients without clinical evidence of lymphadenopathy rarely have positive nodes at the time of surgery. Patients with metastatic disease to the regional lymph nodes have a poor overall prognosis. However, some evidence supports a therapeutic benefit of lymphadenectomy in these patients. Further, the staging information gained from diagnosing lymph node involvement may allow for the use of new agents to treat metastatic disease and effect outcomes.

Reassessment of renal cell carcinoma lymph node staging: analysis of patterns of progression

OBJECTIVES

To evaluate the prognostic value of lymph node (LN) metastasis and the therapeutic role of LN dissection (LND) in patients with renal cell carcinoma.

METHODS

We reviewed the medical records of 1503 patients who had undergone nephrectomy from 1990 to 2007. The patients were stratified according to the number, location, and size of LN metastases. The disease-free survival, cancer-specific survival, and survival relative to the preoperative suspicion of LN metastasis were analyzed.

RESULTS

Of the 1503 patients, 726 (48.3%) had Stage pN0, 37 (2.5%) had Stage pN+, including 16 with pN1 and 21 with pN2, and 740 (49.2%) had Stage pNx. The average number of LNs removed was 5 (range 1-33), and the average size of the metastasized LNs was 2.4 cm (range 0.8-6). Of the patients without preoperative clinical evidence of LN metastasis, 203 underwent LND; all had Stage pN0. The LN stage was a significant predictor of distant metastasis-free survival (P = .002) and cancer-specific survival (P = .001) between the pNx/pN0 and pN+ groups but not between the pN1 and pN2 groups. Metastasized LN size (<3 vs ≥3 cm) also significantly predicted for distant metastasis-free survival (P = .003) and cancer-specific survival (P = .001). In LN-positive patients, LND improved local recurrence-free survival but not distant metastasis-free survival or cancer-specific survival.

CONCLUSIONS

The current LN staging system, which is dependent on the number of metastatic LNs, did not significantly correlate with the prognosis in patients with renal cell carcinoma. In contrast, LN size (<3 vs ≥3 cm) better reflected the effect of this disease on survival. The therapeutic role of LND might be limited.

In search of a better crystal ball: recent advances in prognostic markers for clear-cell renal cell carcinoma

Advances in imaging have led to a steady increase in the incidence of kidney cancer over the last two decades. There has been no corresponding improvement in our ability to predict the behavior of renal cell carcinoma. Patients with low-risk renal cell carcinoma have good long-term survival with only localized therapy but patients with aggressive disease do poorly, even with optimal multimodal treatment. Biomarkers to differentiate between these two very divergent populations have traditionally been of only limited utility. We review the recent advances in the development of molecular and immunologic markers aimed at improving prognostication of renal cell carcinoma.

Prognostic factors in renal cell carcinoma

PURPOSE

Renal cell carcinoma (RCC) is a very heterogeneous disease with widely varying prognosis. An accurate knowledge of the individual risk of disease progression and mortality after treatment is essential to counsel patients, plan individualized surveillance protocols and select patients for adapted treatment schedules and new clinical trials.

METHODS

A systematic review of the literature on prognostic factors of localized and metastatic RCC was performed.

RESULTS

Prognostic factors in RCC include anatomical (TNM classification, tumor size), histological (Fuhrman grade, histologic subtype), clinical (symptoms and performance status), and molecular features. All these features are not perfectly accurate when used alone. Therefore an increasing number of prognostic models or nomograms that include several combined prognostic features have been designed in order to improve predictive accuracy. UCLA Integrated Staging System (UISS) and the Mayo Clinic's SSIGN score are the two most used prognostic models for localized RCC. In the setting of metastatic RCC the classical anatomical and histological tumor features have little predictive value. However, accurate prognostic models have been designed to predict response to therapy, and progression-free and overall survival. The two most used tools to predict response to immunotherapy are the model designed by the French Group of Immunotherapy and the Motzer's model. The advent of tyrosine kinase inhibitors and antiangiogenic drugs have deeply changed the treatment of metastatic RCC. Predictive tools that are adapted to the modern targeted therapies are now needed.

CONCLUSION

There is increasing knowledge on prognostic factors of localized and metastatic RCC. Several predictive models have been developed by combining different prognostic features and are valuable tools for patient counseling, treatment decision-making and trial design. Further research is needed to assess whether the combination of classical prognostic factors with molecular features and information from gene and protein expression profiling can increase the predictive accuracy of the current prognostic models.

Prognostic significance of lymph node invasion in patients with metastatic renal cell carcinoma: a population-based perspective

BACKGROUND

Virtually all staging schemes aimed at predicting the prognosis of surgically treated patients diagnosed with metastatic renal cell carcinoma (MRCC) omit the use of lymph node stage. In the current study, the authors tested the prognostic significance of lymph node stage in patients with MRCC within a population-based cohort of patients treated with cytoreductive nephrectomy to assess whether the inclusion of lymph node stage could improve the accuracy of cancer-specific mortality predictions.

METHODS

Within the Surveillance, Epidemiology, and End Results database, the authors identified 1153 patients who were treated with cytoreductive nephrectomy for MRCC, with (negative lymph nodes [N0] vs positive lymph nodes [N1-2]) or without (unknown lymph node stage [Nx]) lymphadenectomy. Of 797 patients treated with lymphadenectomy, 42.9% were found to have lymph node metastases. Kaplan-Meier plots and univariate and multivariate Cox regression analyses tested the statistical significance and the independent predictor status of lymph node stage, Fuhrman grade, tumor size, year of surgery, race, sex, and age in patients who underwent lymphadenectomy at the time of cytoreductive nephrectomy.

RESULTS

At 3 years after cytoreductive nephrectomy, the cancer-specific mortality-free rates of N1-2 versus N0 versus Nx patients were 14.4% versus 34.7% versus 34.0%, respectively. Lymph node stage represented the most informative variable and achieved independent predictor status in all multivariate models (P<.001). Consideration of lymph node stage added 3.2% accuracy to other predictors of cancer-specific mortality.

CONCLUSIONS

The findings of the current study indicate that lymph node stage should be considered in prognostic models. The TNM staging of MRCC patients also should rely on the stage of locoregional lymph nodes, because the 3-year cancer-specific mortality rates of lymph node-negative and lymph node-positive MRCC patients differ by as much as 20%.

Reassessing the current UICC/AJCC TNM staging for renal cell carcinoma

CONTEXT

The outcome prediction for renal cell cancer (RCC) remains controversial, and although many parameters have been tested for prognostic significance, only a few have achieved widespread acceptance in clinical practice. The TNM staging system defines local extension of the primary tumour (T), involvement of regional lymph nodes (N), and presence of distant metastases (M).

OBJECTIVE

This review focuses on reassessing the current TNM staging system for RCC.

EVIDENCE ACQUISITION

A literature search in English was performed using the National Library of Medicine database and the following keywords: renal cell cancer, kidney neoplasm, and staging. We scrutinized 1952 references, and 62 were selected for review based on their pertinence, study size, and overall contribution to the field.

EVIDENCE SYNTHESIS

The prognostic significance of tumour size for localized RCC has been investigated in a large number of studies. As a consequence, many modifications of the TNM staging system were primarily made to the size cut points between stage I and II tumours. The latest three revisions of the TNM system are systematically reviewed. For the heterogeneous group of locally advanced RCCs, involving different anatomic structures surrounding the kidney, the situation is still the subject of controversial scientific dispute. In detail, perirenal fat invasion, direct infiltration of the ipsilateral adrenal gland, invasion of the urinary collecting system, infiltration of renal sinus fat, and vena cava and renal vein thrombosis are disputed. Finally, staging of lymph node metastases and distant metastatic disease is discussed.

CONCLUSIONS

Special emphasis should be put on renal sinus invasion for stage evaluation. Retrospective studies relying on material collected at a time when no emphasis was placed on adequate sampling of the renal sinus should be treated with caution. In view of new treatment opportunities, the current TNM staging system of RCC and any other staging system must be dynamic.

Advances and controversies in grading and staging of renal cell carcinoma

Despite the considerable progress made in our understanding of the pathogenesis, genetics, and pathology of renal cell carcinoma (RCC), difficulties remain relating to the prediction of clinical outcome for individual cases. Although there is evidence to show that high-grade tumors have a poorer prognosis when compared to those of low grade, debate remains regarding the predictive value of grading, especially for those tumors classified into the intermediate grades. Numerous composite morphologic and nuclear grading systems have been proposed for RCC and although that of the Fuhrman classification have achieved widespread usage, the validity of the grading criteria of this classification has been questioned. In addition, there are few studies that have attempted to validate the Fuhrman system for RCCs beyond that of the clear cell subtype. Recent studies have indicated that grading of papillary RCC should be based on nucleolar prominence alone and that the components of the Fuhrman grading classification do not provide prognostic information for chromophobe RCC. Independent of tumor grade, the prognostic importance of tumor stage for RCC is well recognized. The Union Internationale Contre le Cancer/American Joint Committee for Cancer Staging and End Results Reporting TNM staging system is now in its sixth edition (2002) and recent refinements have focused on defining size cut points that will identify apparently localized tumors that will develop recurrence and/or metastases despite attempted curative surgery. In parallel with these studies it has been shown that infiltration of the renal sinus is an important prognostic factor, being observed in almost all tumors >7 cm in diameter. Questions remain as to the appropriate stratification of regional extension of RCC, as defined in the T3 tumor-staging category. Recent modifications to this category have been suggested combining the level of infiltration of the venous outflow tract with the presence or absence of infiltration of the adrenal gland and/or perirenal fat. Similarly, the utility of classifying lymph node involvement by tumor is debated, although it is well recognized that lymph node infiltration is associated with a poor prognosis. Although the current TNM classification does provide useful prognostic information it would appear that further modifications are justified to enhance the predictive value of staging for RCC.

Tumor lymphatics

In this article we survey more than three centuries of observation and research into tumor-associated lymphatic vessels, and their role in the metastatic spread of cancer. This historical overview documents how questions regarding tumor lymphatics have been central to concepts about the process of metastasis, and how this has subsequently influenced the clinical treatment of cancer. In turn, we show how analysis of the efficacy of these treatments has challenged long-standing notions regarding the tumor lymphatics. Starting with the discovery of VEGFR-3 and its ligands VEGF-C and VEGF-D, we also review how the rapid developments over the last 15 years in the molecular analysis of the lymphatic system and in particular lymphangiogenesis have contributed to this debate. Finally we speculate on how apparently paradoxical bodies of evidence regarding the role of tumor lymphatics in determining patterns of metastatic spread might be reconciled.

The prognostic relevance of interactions between venous invasion, lymph node involvement and distant metastases in renal cell carcinoma after radical nephrectomy

BACKGROUND

To investigate a possible prognostic significance of interactions between lymph node invasion (LNI), synchronous distant metastases (SDM), and venous invasion (VI) adjusted for mode of detection, Eastern Cooperative Oncology Group performance status (ECOG PS), erythrocyte sedimentation rate (ESR) and tumour size (TS) in 196 patients with renal cell carcinoma treated with radical nephrectomy.

METHODS

Median follow-up was 5.5 years (mean 6.9 years; range 0.01-19.4). The mode of detection, ECOG PS, ESR and TS were obtained from the patients' records. Vena cava invasion and distant metastases were detected by preoperative imaging. The surgical specimens were examined for pathological stage, LNI and VI.

RESULTS

The univariate analyses showed significant impact of VI, LNI, SDM, ESR and TS (p < 0.001), as well as mode of detection (p = 0.003) and ECOG PS (p = 0.002) on cancer specific survival. In multivariate analyses LNI was significantly associated with survival only in patients without SDM or VI (p < 0.001) with a hazard ratio of 9.0. LNI lost its prognostic significance when SDM or VI was present.

CONCLUSION

Our findings underline the prognostic importance of the status of the lymph nodes. LNI, SDM, ESR, and VI were independently associated with cancer specific survival after radical nephrectomy. LNI provided the strongest prognostic information for patients without SDM or VI whereas SDM and VI had strongest impact on survival when there was no nodal involvement.

[Value of lymph node dissection for renal cell carcinoma]

There are as yet no common standards regarding lymph node dissection during tumor nephrectomy. In order to assess prognoses and survival rates and ensure early detection of kidney tumors, a pathohistological staging following lymphadenopathy and new adjuvant therapies in metastatic disease have to be established in the future. The aims of lymph node dissection are - as far as the morbidity and performance status of the patient are concerned - accurate staging and a decrease in risk of tumor recurrence, particularly in organ-confined cancer disease.

Perinephric and renal sinus fat infiltration in pT3a renal cell carcinoma: possible prognostic differences

OBJECTIVE

To evaluate the influence of perinephric (PN) and renal sinus (RS) fat infiltration on cancer-specific survival beyond other prognostic factors, as the Tumour-Node-Metastasis (TNM) classification system defines stage T3a renal cell carcinoma (RCC) as infiltration of perirenal fat and/or direct infiltration of the adrenal gland. Perirenal fat invasion is differentiated into RS and PN fat infiltration, but not further classified for the prognosis.

PATIENTS AND METHODS

From 1990 to October 2007 106 patients with advanced RCC (T3a) were followed prospectively at one academic centre; all had a radical nephrectomy. To identify prognostic effects of PN, RS or RS + PN fat infiltration, univariable and multivariable Cox proportional hazard regression models were applied, including lymph node status, metastases, presence of sarcomatoid features and tumour necrosis, Fuhrman's grade, Karnofsky performance status, and tumour size.

RESULTS

PN fat invasion alone was present in 58, RS in 21, and PN + RS in 27 patients. The median follow-up was 2.9 years; 49 patients died from RCC. In univariable and multivariable analyses RS fat infiltration was an unfavourable prognostic factor (adjusted hazard ratio, HR, 2.24, P = 0.019). Univariable analysis of RS + PN fat infiltration showed the worst prognostic effect (HR 3.25, P < 0.001). In multivariable analysis this combination was an independent prognostic factor (HR 2.75, P = 0.007), as was the presence of metastasis (HR 5.64, P < 0.001). In this group of RS + PN fat infiltration the 5-year cancer-specific survival was 31%.

CONCLUSION

Univariable and multivariable analyses showed that the combination of RS and PN fat infiltration is an independent unfavourable prognostic marker. We recommend that perirenal fat infiltration should be further differentiated into RS fat or PN infiltration in the TNM classification. This will better stratify patient prognosis and might allow those in need of adjuvant therapy to be identified.

Stage-specific effect of nodal metastases on survival in patients with non-metastatic renal cell carcinoma

OBJECTIVE

To quantify the survival disadvantage related to the presence of exclusive nodal metastases (eNM) in patients with otherwise non-metastatic (M0) renal cell carcinoma (RCC).

PATIENTS AND METHODS

Data were retrieved from 12 institutional databases and yielded 3507 patients with T1-3N1-2M0 RCC treated with partial or radical nephrectomy. Cox regression analyses relied on T stage, Fuhrman grade and presence of eNM. Data were analysed using univariable, multivariable and stratified analyses.

RESULTS

Overall 165 (4.7%) patients had eNM; of 2023 patients of stage T1, 23 (1.1%) had eNM, vs 20 of 448 (4.5%) for T2 and 122 of 993 (12.3%) for T3. In univariable analyses the presence of eNM increased the rate of cancer specific mortality (CSM) by 7.1 times. After adjusting for T stage and Fuhrman grade, in all patients eNM increased the rate of CSM by 3.2 times. In stratified analyses adjusted for Fuhrman grade, the increase in CSM related to the presence of eNM was 28.9, 4.3 and 2.5 times (all P < 0.001) for stages T1, T2 and T3, respectively.

CONCLUSIONS

From the prognostic perspective, staging lymphadenectomy appears of most value in patients with T1-2 RCC, but the low prevalence of eNM questions the practical applicability of nodal staging in those patients. Conversely, in patients with T3 RCC, the prevalence and the prognostic impact of eNM might make a staging lymphadenectomy worthwhile.

Proposal of an improved prognostic classification for pT3 renal cell carcinoma

PURPOSE

The prognostic accuracy of the current TNM 2002 staging system for locally advanced renal cell carcinoma has been questioned. To contribute to the development of a more accurate classification for this stage of disease we assessed the correlation between patterns of invasion in the pT3 category and outcomes in a large multi-institutional series.

MATERIALS AND METHODS

Pathological data and clinical followup on 513 pT3 renal cell carcinoma cases treated with radical nephrectomy between 1983 and 2005 at 3 Italian academic centers were retrospectively reviewed. Cause specific survival rates were calculated with the Kaplan-Meier method and multivariate analysis was performed using the Cox proportional hazards regression model.

RESULTS

Estimated overall 5-year cause specific survival was 50.1% at a median followup of 61.5 months in survivors. The current TNM classification was not a significant outcome prognosticator. Patients with a tumor invading only the perirenal or sinus fat were at lowest risk for death from the disease. Patients at intermediate risk had tumors with invasion of the venous system alone. Simultaneous perirenal fat and sinus fat invasion or perirenal fat and vascular invasion as well as adrenal gland involvement characterized high risk tumors. Low risk tumors could be further divided into 2 groups with different outcomes based on a size cutoff of 7 cm. Our classification was a significant predictor of survival on multivariate analysis as well as M stage, N stage, Fuhrman grade and tumor size.

CONCLUSIONS

We confirm that the prognostic usefulness of the current 2002 TNM system for pT3 renal cell carcinoma is limited. We have identified 4 groups of tumors with distinct patterns of invasion and significantly different survival probabilities in this category. Large prospective series are needed to validate these findings.