Microvascular tumor invasion, tumor size and Fuhrman grade: a pathological triad for prognostic evaluation of renal cell carcinoma

Development and validation of a nomogram to predict recurrence for clinical T1/2 clear cell renal cell carcinoma patients after nephrectomy

OBJECTIVE

To develop and validate a nomogram for predicting recurrence-free survival (RFS) for clinical T1/2 (cT1/2) clear cell renal cell carcinoma (ccRCC) patients after nephrectomy.

METHODS

Clinicopathological and survival data from 1289 cT1/2 ccRCC patients treated at the Second Hospital of Tianjin Medical University between 2017 and 2020 were included. Cox regression analysis was used to identify independent risk factors in 902 and 387 ccRCC patients in the training and validation cohorts, respectively, and construct the nomogram. The performance of the nomogram was assessed through calibration plots, time-dependent receiver operating characteristic (ROC) curves, C-index (concordance-index), and decision curve analysis (DCA). Kaplan-Meier curves were used to evaluate the probability of RFS in patients with different recurrence risks.

RESULTS

Age, tumor size, surgical approach, Fuhrman grade, and pT3a upstage were identified as independent predictors of RFS. The area under the curve (AUC) for the 3-year and 5-year RFS ROC curves were 0.791 and 0.835 in the training cohort, and 0.860 and 0.880 in the validation cohort. The DCA and calibration plots demonstrated the optimal application and excellent accuracy of the nomogram for predicting 3-year and 5-year RFS. Kaplan-Meier curves revealed significant differences in RFS among the three risk groups in both the training and validation cohorts. Clinically, the developed nomogram provides a more precise tool for risk stratification, enabling tailored postoperative management and surveillance strategies, ultimately aiming to improve patient outcomes.

CONCLUSIONS

We developed a nomogram for predicting RFS in cT1/2 ccRCC patients after nephrectomy with high accuracy. The clinical implementation of this nomogram can significantly enhance clinical decision-making, leading to improved patient outcomes and optimized resource utilization in the management of ccRCC.

The utilization of single-cell sequencing technology in investigating the immune microenvironment of ccRCC

The growth and advancement of ccRCC are strongly associated with the presence of immune infiltration and the tumor microenvironment, comprising tumor cells, immune cells, stromal cells, vascular cells, myeloid-derived cells, and extracellular matrix (ECM). Nevertheless, as a result of the diverse and constantly evolving characteristics of the tumor microenvironment, prior advanced sequencing methods have frequently disregarded specific less prevalent cellular traits at varying intervals, thereby concealing their significance. The advancement and widespread use of single-cell sequencing technology enable us to comprehend the source of individual tumor cells and the characteristics of a greater number of individual cells. This, in turn, minimizes the impact of intercellular heterogeneity and temporal heterogeneity of the same cell on experimental outcomes. This review examines the attributes of the tumor microenvironment in ccRCC and provides an overview of the progress made in single-cell sequencing technology and its particular uses in the current focus of immune infiltration in ccRCC.

Breaking down tumor thrombus: Current strategies for medical management

Tumor thrombus, the intravascular extension of tumor into adjacent blood vessels, is frequently encountered in patients with renal cell carcinoma and hepatocellular carcinoma, and often involves the abdominal vasculature including the renal vein, portal vein, and the inferior vena cava. While a bland thrombus is composed of platelets and fibrin, in contrast, a tumor thrombus refers to an organized collection of tumor cells. Though oftentimes detected incidentally on imaging, tumor thrombus may have significant clinical implications and can be challenging to differentiate from bland thrombus. Additionally, the optimal management of tumor thrombus, including the use of anticoagulation, remains poorly described. This review summarizes common causes of tumor thrombus, as well as its impact on staging, prognosis, and treatment.

Artificial Intelligence in Renal Cell Carcinoma Histopathology: Current Applications and Future Perspectives

Renal cell carcinoma (RCC) is characterized by its diverse histopathological features, which pose possible challenges to accurate diagnosis and prognosis. A comprehensive literature review was conducted to explore recent advancements in the field of artificial intelligence (AI) in RCC pathology. The aim of this paper is to assess whether these advancements hold promise in improving the precision, efficiency, and objectivity of histopathological analysis for RCC, while also reducing costs and interobserver variability and potentially alleviating the labor and time burden experienced by pathologists. The reviewed AI-powered approaches demonstrate effective identification and classification abilities regarding several histopathological features associated with RCC, facilitating accurate diagnosis, grading, and prognosis prediction and enabling precise and reliable assessments. Nevertheless, implementing AI in renal cell carcinoma generates challenges concerning standardization, generalizability, benchmarking performance, and integration of data into clinical workflows. Developing methodologies that enable pathologists to interpret AI decisions accurately is imperative. Moreover, establishing more robust and standardized validation workflows is crucial to instill confidence in AI-powered systems' outcomes. These efforts are vital for advancing current state-of-the-art practices and enhancing patient care in the future.

Risk models for recurrence and survival after kidney cancer: a systematic review

OBJECTIVE

To systematically identify and compare the performance of prognostic models providing estimates of survival or recurrence of localized renal cell cancer (RCC) in patients treated with surgery with curative intent.

MATERIALS AND METHODS

We performed a systematic review (PROSPERO CRD42019162349). We searched Medline, EMBASE and the Cochrane Library from 1 January 2000 to 12 December 2019 to identify studies reporting the performance of one or more prognostic model(s) that predict recurrence-free survival (RFS), cancer-specific survival (CSS) or overall survival (OS) in patients who have undergone surgical resection for localized RCC. For each outcome we summarized the discrimination of each model using the C-statistic and performed multivariate random-effects meta-analysis of the logit transformed C-statistic to rank the models.

RESULTS

Of a total of 13 549 articles, 57 included data on the performance of 22 models in external populations. C-statistics ranged from 0.59 to 0.90. Several risk models were assessed in two or more external populations and had similarly high discriminative performance. For RFS, these were the Sorbellini, Karakiewicz, Leibovich and Kattan models, with the UCLA Integrated Staging System model also having similar performance in European/US populations. All had C-statistics ≥0.75 in at least half of the validations. For CSS, they the models with the highest discriminative performance in two or more external validation studies were the Zisman, Stage, Size, Grade and Necrosis (SSIGN), Karakiewicz, Leibovich and Sorbellini models (C-statistic ≥0.80 in at least half of the validations), and for OS they were the Leibovich, Karakiewicz, Sorbellini and SSIGN models. For all outcomes, the models based on clinical features at presentation alone (Cindolo and Yaycioglu) had consistently lower discrimination. Estimates of model calibration were only infrequently included but most underestimated survival.

CONCLUSION

Several models had good discriminative ability, with there being no single 'best' model. The choice from these models for each setting should be informed by both the comparative performance and availability of factors included in the models. All would need recalibration if used to provide absolute survival estimates.

Correlação entre os Parâmetros Clínicos, Patológicos e a Sobrevida Livre de Doença de Pacientes com Câncer Renal Tratados com Cirurgia em um Centro Oncológico do Sistema Público de Curitiba

Introdução: O câncer renal corresponde a 13a neoplasia mais incidente no mundo, sendo o terceiro tipo de câncer geniturinário mais comum. A maioria dos pacientes e assintomática, ocorrendo o diagnóstico de maneira incidental durante a realização de exames de imagem. O tratamento padrão-ouro e o cirúrgico. Objetivo: Correlacionar os parâmetros clínicos e patológicos com a sobrevida livre de doença em pacientes com câncer renal submetidos à nefrectomia. Método: Estudo retrospectivo com 99 pacientes submetidos a tratamento cirúrgico do câncer renal no período de 2010 a 2020. Foram comparados os parâmetros clínicos e patológicos com o desfecho clinico oncológico após nefrectomia. Resultados: Os 99 pacientes tiveram seguimento pós-operatório médio de 26,9 meses, sendo a sobrevida livre de doença (media) de 61,9%. A análise univariada demonstrou que as variáveis tamanho de tumor >7 cm e graus de Fuhrman III e IV estiveram relacionadas a progressão de doença após a nefrectomia (p=0,046 e IC=1,017-7,083; p=0,005 e IC=1,725-23,004, respectivamente). Na análise multivariada, o tamanho do tumor >7 cm (p=0,014 e IC=1,290-9,326) e os graus de Fuhrman III e IV (p=0,028 e IC=1,174-16,616) foram identificados como fatores preditores a progressão. Conclusão: O tamanho tumoral >7 cm e/ou os graus III ou IV de Fuhrman são fatores de risco para recorrência tumoral após o tratamento cirúrgico do câncer renal.

Tumor thrombus formation in the right common iliac vein after radical proctectomy in a patient with rectal cancer: a case report

Background

Intravascular tumor thrombi are mainly found in patients with liver cancer or renal carcinoma but rarely occur in those with rectal cancer.

Case presentation

This is a case report of a 58-year-old woman with a swollen right lower extremity 14 months after radical resection for rectal cancer. Although ultrasonography indicated the presence of deep venous thrombosis (DVT) located in the right common iliac vein, interventional angiography showed that a circular mass, considered a tumor thrombus, was located in the right common iliac vein. The tumor thrombus was cured by interventional therapy, and the pathological report confirmed that the metastatic tumor thrombus originated from the rectal cancer. The patient underwent concurrent chemoradiotherapy and systemic therapy. However, right lung, retroperitoneum, and 2nd sacral vertebral metastases were discovered during follow-up.

Conclusion

The correct diagnosis of a tumor thrombus and its differentiation from DVT can prevent incorrect treatment and prolong the survival of patients with rectal cancer.

Kidney Cancer, Version 3.2022, NCCN Clinical Practice Guidelines in Oncology

The NCCN Guidelines for Kidney Cancer focus on the screening, diagnosis, staging, treatment, and management of renal cell carcinoma (RCC). Patients with relapsed or stage IV RCC typically undergo surgery and/or receive systemic therapy. Tumor histology and risk stratification of patients is important in therapy selection. The NCCN Guidelines for Kidney Cancer stratify treatment recommendations by histology; recommendations for first-line treatment of ccRCC are also stratified by risk group. To further guide management of advanced RCC, the NCCN Kidney Cancer Panel has categorized all systemic kidney cancer therapy regimens as "Preferred," "Other Recommended Regimens," or "Useful in Certain Circumstances." This categorization provides guidance on treatment selection by considering the efficacy, safety, evidence, and other factors that play a role in treatment selection. These factors include pre-existing comorbidities, nature of the disease, and in some cases consideration of access to agents. This article summarizes surgical and systemic therapy recommendations for patients with relapsed or stage IV RCC.

Overall Survival Prediction in Renal Cell Carcinoma Patients Using Computed Tomography Radiomic and Clinical Information

The aim of this work is to investigate the applicability of radiomic features alone and in combination with clinical information for the prediction of renal cell carcinoma (RCC) patients’ overall survival after partial or radical nephrectomy. Clinical studies of 210 RCC patients from The Cancer Imaging Archive (TCIA) who underwent either partial or radical nephrectomy were included in this study. Regions of interest (ROIs) were manually defined on CT images. A total of 225 radiomic features were extracted and analyzed along with the 59 clinical features. An elastic net penalized Cox regression was used for feature selection. Accelerated failure time (AFT) with the shared frailty model was used to determine the effects of the selected features on the overall survival time. Eleven radiomic and twelve clinical features were selected based on their non-zero coefficients. Tumor grade, tumor malignancy, and pathology t-stage were the most significant predictors of overall survival (OS) among the clinical features (p < 0.002, < 0.02, and < 0.018, respectively). The most significant predictors of OS among the selected radiomic features were flatness, area density, and median (p < 0.02, < 0.02, and < 0.05, respectively). Along with important clinical features, such as tumor heterogeneity and tumor grade, imaging biomarkers such as tumor flatness, area density, and median are significantly correlated with OS of RCC patients.

Prediction models for clear cell renal cell carcinoma ISUP/WHO grade: comparison between CT radiomics and conventional contrast-enhanced CT

OBJECTIVE

Comparing the prediction models for the ISUP/WHO grade of clear cell renal cell carcinoma (ccRCC) based on CT radiomics and conventional contrast-enhanced CT (CECT).

METHODS

The corticomedullary phase images of 119 cases of low-grade (I and II) and high-grade (III and IV) ccRCC based on 2016 ISUP/WHO pathological grading criteria were analyzed retrospectively. The patients were randomly divided into training and validation set by stratified sampling according to 7:3 ratio. Prediction models of ccRCC differentiation were constructed using CT radiomics and conventional CECT findings in the training setandwere validated using validation set. The discrimination, calibration, net reclassification index (NRI) and integrated discrimination improvement index (IDI) of the two prediction models were further compared. The decision curve was used to analyze the net benefit of patients under different probability thresholds of the two models.

RESULTS

In the training set, the C-statistics of radiomics prediction model was statistically higher than that of CECT (p < 0.05), with NRI of 9.52% and IDI of 21.6%, both with statistical significance (p < 0.01).In the validation set, the C-statistics of radiomics prediction model was also higher but did not show statistical significance (p = 0.07). The NRI and IDI was 14.29 and 33.7%, respectively, both statistically significant (p < 0.01). Validation set decision curve analysis showed the net benefit improvement of CT radiomics prediction model in the range of 3-81% over CECT.

CONCLUSION

The prediction model using CT radiomics in corticomedullary phase is more effective for ccRCC ISUP/WHO grade than conventional CECT.

ADVANCES IN KNOWLEDGE

As a non-invasive analysis method, radiomics can predict the ISUP/WHO grade of ccRCC more effectively than traditional enhanced CT.

Recurrence risk groups after nephrectomy for renal cell carcinoma

INTRODUCTION

There is no consensus on the follow-up protocol after nephrectomy for renal cell carcinoma (RCC), and the identification of recurrence risk groups (RRG) is required.

OBJECTIVE

Establish recurrence risk groups (RRG).

MATERIAL AND METHOD

A retrospective analysis of 696 patients with renal cancer submitted to surgery between 1990-2010; 568 (81.6%) patients treated with radical nephrectomy and 128 (18.4%) treated with partial nephrectomy. Pathological variables were classified as: 1st-level variables (1LPV): pTpN stage and Fuhrman grade (FG); and 2nd level pathological variables (2LPV): sarcomatoid differentiation (SD), tumor necrosis (TN), microvascular invasion (MVI) and positive surgical margins (PSM). Univariate and multivariate analysis have been performed using Cox regression to determine 1LPV related to recurrence. Based on 1LPV, we classified patients into three RRG: Low (LRG)<25%; Intermediate (IRG) 26-50% and High (HRG)>50%. We performed univariate and multivariate analysis with the 2LPVs for each RRG. With these data, patients were reclassified as RRG+. ROC curves were used for comparison of RRG and RRG+.

RESULTS

The median follow-up was 105 months (range 63 to 148). There were 177 (25.4%) patients with recurrence: 111 (15.9%) distant, 34 (4.9%) local and 32 (4.6%) distant and local. In the multivariable analysis, Fuhrman grade (HR=2,75; P=.0001) and pTpN stage (HR=2,19; P=.0001) behaved as independent predictive variables of recurrence. Patients were grouped as RRG (AUC=0,76; p=0,0001): - LRG (pT1pNx-0 G1-4; pT2pNx-0 G1-2): 456 (65,5%) patients. - IRG (pT2pNx-0 G3-4; pT3-4pNx-0 G1-2): 110 (15,8%) patients. - HRG (pT3-4pNx-0 G3-4; pT1-4pN+): 130 (18,6%) patients. After multivariate analysis with 2LPV, RRG were reclassified (RRG+) (AUC=.84, P=.0001): -LRG+(LRG without TN, SD and/or PSM(+)). -IRG+(IRG; LRG with TN) -HRG+(HRG; LRG with SD and/or PSM(+); IRG with TN and/or SD) CONCLUSIONS: The inclusion of 2LPV to the classification according to VP1N improves the discriminating capacity of RRG classification.

Programmed Death Ligand 1; An Immunotarget for Renal Cell Carcinoma

BACKGROUND

In this era of developing targeted therapies and immunotherapies as a treatment for renal cell carcinoma (RCC), Programmed death ligand 1 (PDL1) as a novel biomarker for RCC is analysed in our study. About 90% of all renal cancers are Renal Cell Carcinoma. Most cases are diagnosed incidentally. 17% of cases are advanced at the time of diagnosis. PDL1 being a trans-membrane cell surface protein is expressed on the tumor cells and is found to have a chief role to inhibit the T cell immune response. It is essential to improve the host immunity by targeting the PD1/PDL1 pathway, thereby destroying the tumor progression.

AIM

The aim of this study was to evaluate the expression of PDL1 in tumor cells and adjacent normal tissue among the renal cell carcinoma patients and assess the relation between the PDL1 expression and the tumor characters.

METHODS

This is a retrospective study. Ethical clearance was obtained from the institution. 150 histopathologically proven RCC cases were chosen. Immunohistochemistry using a PD-L1 rabbit monoclonal antibody was performed on paraffin embedded formalin fixed tissue blocks. Q scoring was done to calculate the expression of PDL1.

STATISTICAL ANALYSIS

Chi square test was done to assess the comparison between the PDL1 expression in tumor cells and their characteristic features like histology, grade and stage. SPSS (version 20.0) was used for analysis. P value <0.05 was considered significant. It also explains the heterogenous nature of PDL1 as it expressed more in the aggressive pathologic characters like high grade.

RESULTS

Positive PD-L1 expression was seen in 44% of tumors. Significant association was observed between high WWHO ISUP grading and positive PDL1 expression (p=0.028). It was expressed in 75% of the sarcomatous type of RCC and 46.8% of clear cell RCCs.

CONCLUSION

Our study suggests that blocking PD1/PDL1 pathway may become an effective mode of treatment in cancer immunotherapy especially for Renal Cell Carcinomas. Our findings confirmed the significant association between expression of PDL1 and the high graded tumors which proves it to be an important prognostic factor.

Frequency, incidence and survival outcomes of clear cell renal cell carcinoma in the United States from 1973 to 2014: A SEER-based analysis

The epidemiological and prognostic data focusing on clear cell renal cell carcinoma (ccRCC) are rarely presented. This study was aimed to define the frequency, incidence, and survival outcomes of ccRCC in the United States.The Surveillance, Epidemiology, and End Results (SEER) database was searched for patients with ccRCC from 1973 to 2014. Two patient cohorts were utilized: patient cohorts of SEER 18 registries and 9 registries. Overall survival was determined with Kaplan-Meier method and compared across groups with log-rank test.The incidence rate of ccRCC increased with advancing age, peaked in individuals aged 60 to 79 years, and declined in individuals aged ≥80 years. The incidence rate of ccRCC was significantly higher in males than females (1.94: 1, P < .0001), in Whites than Blacks or others (1:0.79:0.91, P < .0001). The incidence rate of ccRCC with right side as primary origin was slightly but significantly higher than that with left side as primary origin (1:0.96, P = .0006). The incidence rate of ccRCC in Grade II was higher than other grades. Generally, the incidence rates of ccRCC in most circumstances started to surge in the middle 1990s. Survival outcomes of ccRCC worsened with advancing age at diagnosis, tumor grade, and stage. A better prognosis was observed in females than males, in Whites than Blacks, and in individuals diagnosed in 2006 to 2014 than 1973 to 2005.To the best of our knowledge, the present study firstly presented long-term and updated epidemiological and prognostic data concerning ccRCC in the United States. Significant differences in incidence rates and survival outcomes stratified by different variables were identified.

Early post-operative serum albumin level predicts survival after curative nephrectomy for kidney cancer: a retrospective study

BACKGROUND

Previous studies have shown that albumin-related systemic inflammation is associated with the long-term prognosis of cancer, but the clinical significance of an early (≤ 7 days) post-operative serum albumin level has not been well-documented as a prognostic factor in patients with renal cell cancer.

METHODS

We retrospectively included patients hospitalized for kidney cancer from January 2009 to May 2014. First, the receiver operating characteristic analysis was used to define the best cut-off of an early post-operative serum albumin level in determining the prognosis, from which survival analysis was performed.

RESULTS

A total of 329 patients were included. The median duration of follow-up was 54.8 months. Patients with an early post-operative serum albumin level < 32 g/L had a significantly shorter median recurrence-free survival (RFS; 49.1 versus 56.5 months, P = 0.001) and median overall survival (OS; 52.2 versus 57.0 months, P = 0.049) than patients with an early post-operative serum albumin level ≥ 32 g/L. After adjusting for age, BMI, tumor stage, post-operative hemoglobin concentration, and pre-operative albumin, globulin, and hemoglobin levels, multivariate Cox regression showed that an early post-operative serum albumin level < 32 g/L was an independent prognostic factor associated with a decreased RFS (HR = 3.60; 95% CI,1.05-12.42 [months], P = 0.042) and decreased OS (HR = 9.95; 95% CI, 1.81-54.80 [months], P = 0.008).

CONCLUSION

An early post-operative serum albumin level < 32 g/L is an independent prognostic factor leading to an unfavorable RFS and OS. Prospective trials and further studies involving additional patients are warranted.

Delayed enhancement of the peritumoural cortex in clear cell renal cell carcinoma: correlation with Fuhrman grade

AIM

To assess the delayed enhancement of the peritumoural cortex (DEC) sign in clear cell renal cell carcinoma (ccRCC), and investigate a possible correlation among DEC and Fuhrman grade.

MATERIALS AND METHODS

This retrospective study included 506 patients with 511 histopathologically proven ccRCCs evaluated by computed tomography (CT) angiography. DEC was detected and compared in groups divided by Fuhrman grades (low grade: 1 and 2, high grade: 3 and 4) using univariate and multivariate analyses.

RESULTS

DEC was detected in 89 of 511 (17.4%) ccRCCs (grade 1: 5.7%, 2/35; grade 2: 16.2%, 70/433; grade 3: 31.4%, 11/35; grade 4: 75%, 6/8; p<0.001). The incidence was higher in high-grade ccRCCs (39.5%, 17/43) than in low-grade ccRCCs (15.4%, 72/468; p<0.001). In multivariate analysis, tumour size >5.4 cm (p<0.001, odds ratio [OR]=3.57, 95% confidence interval [CI]: 1.76-7.23) and detection of DEC (p=0.021, OR=2.33, 95% CI: 1.13-4.80) were independent predictors of high-grade ccRCC. For all ccRCCs, the area under the receiver operating characteristic (ROC) curve (AUC) of DEC in predicting high-grade ccRCC was 0.62 (95% CI: 0.53-0.72) with 39.5% sensitivity and 84.6% specificity, while for ccRCCs of >5.4 cm diameter, the AUC was 0.66 (95% CI: 0.52-0.80) with 68.4% sensitivity and 62.7% specificity.

CONCLUSIONS

The DEC sign may predict aggressive biological behaviour of ccRCC, irrespective of tumour size.

Renal capsular invasion is a prognostic biomarker in localized clear cell renal cell carcinoma

Renal capsular invasion (RCI) and lymphovascular invasion (LVI) are potential prognostic factors of significance in renal cell carcinoma (RCC). We evaluated the independent prognostic implications of RCI and LVI in localized clear cell RCC based on a large multi-institutional cohort. 6, 849 patients who had undergone radical or partial nephrectomy for RCC were included. Associations between recurrence and RCI or LVI were analyzed by constructing statistical models that combined Cox proportional hazard regression and propensity score matching. To analyze RCI, 2, 733 patients including 603 patients with RCI were enrolled. To analyze LVI, 3, 586 patients including 121 patients with LVI were enrolled. Recurrence was observed in 75 (12.4%) patients with RCI and 134 (6.3%) patients without RCI. In all statistical models, RCI was significantly associated with an increased risk of recurrence. Recurrence was observed 29 (24.0%) patients with LVI and 207 (6.0%) patients without LVI. LVI was significantly associated with an increased risk of recurrence only in non-adjusted univariate models, but not in multivariate adjusted analysis or propensity score matching models. In conclusion, these findings suggest that RCI could be a significant risk factor for localized clear cell RCC recurrence. In contrast to RCI, LVI cannot be an independent prognostic variable.

Tumor thrombus: incidence, imaging, prognosis and treatment

Intravascular tumor extension, also known as tumor thrombus, can occur in many different types of cancer. Those with the highest proclivity include Wilm's tumor, renal cell carcinoma (RCC), adrenal cortical carcinoma (ACC) and hepatocellular carcinoma (HCC). The presence of tumor thrombus markedly worsens prognosis and impacts treatment approach. Imaging plays a key role in its diagnosis. Endovascular methods also play a large role in treatment.

Systematic review of renal carcinoma prognostic factors

CONTEXT AND OBJECTIVES

The natural history of renal cell carcinoma is heterogeneous. Some scenarios can be found in terms of clinical presentation, clinical evolution or type of recurrence (local/metastatic). The aim of this publication is to analyze the most important prognostic factors published in the literature.

EVIDENCE ACQUISITION

A literature review ob published papers was performed using the Pubmed, from first Motzer's classification published in 1999 to 2015, according to PRISMA declaration. Search was done using the following keywords: kidney neoplasm, kidney cancer, renal cell carcinoma, prognostic factors, mortality, survival and disease progression. Papers were classified according to level of evidence, the number of patients included and the type of study performed.

EVIDENCE SYNTHESIS

The evolution in the knowledge of molecular pathways related to renal oncogenesis and the new targeted therapies has left to remain obsolete the old prognostic models. It's necessary to perform a continuous review to actualize nomograms and to adapt them to the new scenarios.

CONCLUSIONS

Is necessary to perform a proper external validation of existing prognostic factors using prospective and multicentric studies to add them into the daily urologist clinical practice.

Tumor size, stage and grade alterations of urinary peptidome in RCC

Background

Several promising biomarkers have been found for RCC, but none of them has been used in clinical practice for predicting tumour progression. The most widely used features for predicting tumour aggressiveness still remain the cancer stage, size and grade. Therefore, the aim of our study is to investigate the urinary peptidome to search and identify peptides whose concentrations in urine are linked to tumour growth measure and clinical data.

Methods

A proteomic approach applied to ccRCC urinary peptidome (n = 117) based on prefractionation with activated magnetic beads followed by MALDI-TOF profiling was used. A systematic correlation study was performed on urinary peptide profiles obtained from MS analysis. Peptide identity was obtained by LC–ESI–MS/MS.

Results

Fifteen, twenty-six and five peptides showed a statistically significant alteration of their urinary concentration according to tumour size, pT and grade, respectively. Furthermore, 15 and 9 signals were observed to have urinary levels statistically modified in patients at different pT or grade values, even at very early stages. Among them, C1RL, A1AGx, ZAG2G, PGBM, MMP23, GP162, ADA19, G3P, RSPH3, DREB, NOTC2 SAFB2 and CC168 were identified.

Conclusions

We identified several peptides whose urinary abundance varied according to tumour size, stage and grade. Among them, several play a possible role in tumorigenesis, progression and aggressiveness. These results could be a useful starting point for future studies aimed at verifying their possible use in the managements of RCC patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-015-0693-8) contains supplementary material, which is available to authorized users.

PD-L1 expression in renal cell carcinoma clear cell type is related to unfavorable prognosis

Background

PD-L1 is a glycoprotein from the family of T-cell co-stimulatory molecules that are constitutively expressed by macrophages. Aberrant expression of PD-L1 is observed in human cancers associated with inhibition of the tumor-directed T-cell immune response. There are few reports in the literature evaluating PD-L1 expression in association to prognosis specifically in renal cell cancer clear cell type (RCC-CC).

Methods

Immunohistochemistry using a PD-L1 polyclonal antibody was performed on a tissue microarray (TMA) that contained 115 surgical specimens of RCC-CC. Cases were classified based on the absence or presence of staining intensity in the cytoplasm and membranes of the tumor cells. Statistical analysis was used to determine the association of PD-L1 expression with classic prognostic factors and tumor recurrence.

Results

PD-L1 expression was positive in 56.5 % of tumors. The univariate analysis showed a correlation between PD-L1 expression and nuclear Fuhrman grade (p = 0.021) and microvascular tumor embolization (p = 0.039). One hundred and four patients were monitored for a mean time of 115.7 months. Seventeen patients (16.3 %) suffered tumor recurrence. Negative outcomes were associated with higher nuclear grade tumors, PD-L1 expression, and the presence of microvascular invasion.

Conclusion

Our findings confirm that PD-L1 expression is an important prognostic factor in RCC-CC.

Apparent diffusion coefficient: An associative factor for recurrence after nephrectomy in localized renal cell carcinoma

PURPOSE

To investigate whether the apparent diffusion coefficient (ADC) of a tumor is associated with recurrence after nephrectomy in renal cell carcinoma (RCC) MATERIALS AND METHODS: We retrospectively studied 49 patients with localized RCC who underwent 1.5T magnetic resonance imaging (MRI) including diffusion-weighted imaging preoperatively. Fifteen patients had recurrent disease after surgery. The ADC was measured by placing a region-of-interest in a solid region of each tumor on the ADC map. We named the average value of the three ADC values the "average ADC" and the lowest ADC value among the three as the "minimum ADC." The correlations between clinicopathological factors including patient age and gender, tumor side, tumor size, growth/invasion pattern, Fuhrman grade, histological subtype, venous invasion, average and minimum ADCs, and disease-free survival were analyzed by Cox proportional hazards model.

RESULTS

In univariate analysis, tumor size, venous invasion, mean ADC, and minimum ADC showed significant correlations with disease-free survival (P < 0.05). In multivariate analysis, only venous invasion and minimum ADC were significant (P < 0.05). The 5-year disease-free survival rate of the low minimum ADC group was 51.6%, while that of the high minimum ADC group was 85.1%.

CONCLUSION

The minimum ADC of a tumor, although not as pronounced as venous invasion, was found to be an independent associative factor for recurrence after nephrectomy in patients with localized RCC.

Impact of Microvascular Invasion and Tumor Necrosis on the Prognosis of Korean Patients with pT1b Renal Cell Carcinoma

OBJECTIVES

To evaluate prognostic factors in pT1b renal cell carcinoma (RCC) patients for which no specific studies have been conducted on.

METHODS

The data of 270 patients diagnosed with pT1bN0M0 RCC at 2 institutions between January 1998 and June 2010 were retrospectively analyzed. Univariate and multivariate analyses using Cox proportional hazard models were used to identify pathologic and clinical factors that influenced prognosis. Five-year recurrence-free survival and cancer-specific survival were analyzed using the Kaplan-Meier method.

RESULTS

The median follow-up period was 55.5 months, and the mean patient age was 55.2 years (range: 26-80). There were 12 cancer-related deaths, and tumor recurrence was noted in 22 patients between 8 and 120 months after surgery. Sites of metastases included the lung in 13 patients, bone in 5 patients, and other sites in 4 patients. Five-year recurrence-free survival and cancer-specific survival rates were 91.2 and 93.5%, respectively. Multivariate analyses revealed that the presence of microvascular invasion and tumor necrosis independently predicted prognosis.

CONCLUSIONS

Microvascular invasion and tumor necrosis were found to be independent prognostic factors in pT1b RCC. This result will help urologists to provide patients with more accurate prognoses, and patients with confirmed microvascular invasion and tumor necrosis will require closer follow-up.

Inferior vena cava tumor thrombus after partial nephrectomy for renal cell carcinoma

Background

Partial nephrectomy is now the gold standard treatment for small renal tumors. Local recurrence is a major problem after partial nephrectomy, and local recurrence in the remnant kidney after partial nephrectomy is common.

Case presentation

A 77-year-old man underwent right partial nephrectomy for a T1 right renal cell carcinoma. Microscopic examination revealed a clear cell renal carcinoma, grade 2, stage pT3a. Although the surgical margin was negative, the carcinoma invaded the perirenal fat, and vascular involvement was strongly positive. Thirty months after partial nephrectomy, an enhanced computed tomographic scan showed local recurrence of the renal cell carcinoma extending into the inferior vena cava without renal mass. Hence, we performed right radical nephrectomy and intracaval thrombectomy. Microscopic examination revealed a clear cell carcinoma grade 2, stage pT3a + b. The patient is still alive with no evidence of recurrence 10 months post-procedure.

Conclusion

To our knowledge, local recurrence of renal cell carcinoma extending into the inferior vena cava after partial nephrectomy has not been reported in the literature. Our case report emphasizes the importance of strict surveillance of patients after partial nephrectomy, especially for those with renal cell carcinoma positive for microvessel involvement.

Chromosome 9p deletions are an independent predictor of tumor progression following nephrectomy in patients with localized clear cell renal cell carcinoma

OBJECTIVES

Chromosome 9p deletions have been observed in 14% to 36% of patients with clear cell renal cell carcinoma (ccRCC) and are associated with advanced-stage tumors. We evaluated whether chromosome 9p deletions are an independent predictor of worse outcomes in patients with localized ccRCC.

MATERIALS AND METHODS

In this retrospective study, tumor samples from 94 patients with ccRCC NX-0 M0 who underwent radical nephrectomy or conservative renal surgery were analyzed using a fluorescence in situ hybridization technique.

RESULTS

The median follow-up period was 11.7 years, and 9p deletions were identified in 15% of cases. The cancer-specific survival rate estimated at 5 and 10 years was 99% and 96%, respectively, for patients without such chromosomal losses and 71% and 57% in patients with a loss of 9p (P<0.001). Chromosome 9p deletions were an independent prognostic factor in a multivariate analysis, increasing the risk of death due to disease by 28-fold (95% CI: 5-155, P<0.001). In patients with a low risk of progression, i.e., a low Stage, Size, Grade, and Necrosis score (0-2), low risk according to the University of California at Los Angeles Integrated Staging System, and low risk according to the pathological triad used at University of Sao Paulo, tumors with 9p deletions were significantly associated with a poorer cancer-specific survival at 10 years: 70%, 67%, and 67% vs. 98%, 97%, and 98%, respectively, in patients without 9p deletions.

CONCLUSION

Chromosome 9p deletions independently establish a poorer prognosis for patients with localized ccRCC, providing further relevant clinical information that may improve the predictive ability of the main prognostic systems currently in use.

Invasion and metastasis of renal cell carcinoma

Renal cell carcinoma (RCC) represents over 80% of kidney cancer, and about 30% of the patients with RCC develop metastasis after the surgery. Invasion of basement membrane (BM) and extracellular matrix (ECM) is an essential event in tumor invasion and metastasis. Matrix metalloproteinases (MMPs), which digest the main components of BM and ECM, are expressed in RCC. Heparanase, which degrades heparan sulfate proteoglycans, is predominantly expressed in high-grade RCCs with a positive correlation with pathological tumor stage and poor prognosis. Bone metastasis is common among the patients with RCC, and increased osteoclastic activity was observed at metastatic sites. Receptor activator of nuclear factor κB ligand (RANKL), which plays an important role in osteoclastogenesis, is predominantly expressed in high-grade RCC and its expression level is associated with bone metastasis and prognosis. Epithelial-mesenchymal transition (EMT), a switch of epithelial cells to sarcomatoid phenotype, is considered to be critical step during metastasis, and Snail, a major regulator of EMT, is predominantly expressed in high-grade RCC, and high Snail expression is a worse prognostic factor. Accordingly, heparanase, RANKL and Snail may be targets for the development of anti-tumor therapies for RCCs.

Growth pattern, an important pathologic prognostic parameter for clear cell renal cell carcinoma

OBJECTIVES

To assess the validity of growth pattern as a unique prognostic parameter for clear cell renal cell carcinoma (ccRCC).

METHODS

In total, 561 patients with pathologic tumor stage 1 (pT1), pT2, and pT3a ccRCC without preoperative metastasis were evaluated. Clinicopathologic parameters, including pathologic tumor stage, Fuhrman grade, tumor necrosis, lymphovascular invasion, and growth pattern, were analyzed to predict disease-free survival (DFS) and cancer-specific survival (CSS).

RESULTS

Growth patterns were defined as follows: expansive included tumors with well-circumscribed margins without normal renal tissue in the tumor, and infiltrative involved tumors with ill-circumscribed margins or normal renal tissue in the tumors. In multivariate analysis, Fuhrman grade, tumor necrosis, and growth pattern were useful predictors of DFS, whereas Fuhrman grade and growth pattern were useful predictors of CSS, although only 30 cases showed the infiltrative pattern.

CONCLUSIONS

Growth pattern can be considered a new prognostic parameter for ccRCC.

[Relevance of the clinical-pathological predictive factors in force in chromophobe renal cell cancer]

INTRODUCTION

The identification of new subtypes of renal cell carcinoma (RCC) has made it necessary to re-evaluate the current clinical and pathological predictive factors (stage, Fuhrman nuclear grade, necrosis, lymphovascular invasion [LVI] and sarcomatoid component) in these new subtypes. The chromophobe renal cell carcinoma (CRCC) is considered a less aggressive subtype of RCC. The purpose of this article is to evaluate the usefulness of current clinicopathologic predictors of RCC in our series of CRCC.

MATERIAL AND METHODS

We retrospectively reviewed the clinicopathologic features of 63 patients with CRCC treated with radical nephrectomy. The parameters analyzed were tumor extension with the TNM, grade according to Fuhrman classification, LVI, tumor necrosis, tumor thrombus, surgical margin status, and involvement of the collecting system. The results (disease recurrence) were evaluated by Cox regression model with univariate and multivariate analysis.

RESULTS

With a median follow up of 60.2 months (0.37-160.2), 8 (11%) patients had recurrence, with median time to recurrence of 31.7 months (5.37-124.33). In the univariate analysis, TNM extension (p=0.0001), Fuhrman grade III or IV (p=0.031), LVI (p=0.0001) and the presence of positive surgical margins (p=0.0001) were statistically significant variables for recurrence. In the multivariate analysis, only tumor stage was confirmed as an independent predictor of recurrence, pT1 versus pT2 (p=0.02, OR 0.27 95% CI 0.03-0.258) and pT2 versus higher stage (p=0.037, OR 0.173 95% CI 0.033-0.896).

CONCLUSIONS

The tumor stage predicts aggressiveness in the CCRC. The classification of Fuhrman nuclear grade is not useful for this histological subtype.

Unclassified renal cell carcinoma: a report of 56 cases

What's known on the subject? and What does the study add? Unclassified RCC represents 0.7-5.7% of renal tumours. Limited reported data from two series suggests that unclassified RCC is an aggressive form of RCC, mainly because most cases are at an advanced stage at presentation, but overall and cancer-specific survival were not significantly different between unclassified and clear-cell RCC in an additional series of 38 patients. Our study of 56 cases of unclassified RCC describes the pathological features that can be applied to predict prognosis on a daily basis. In particular nuclear grade, TNM classification, tumour coagulative necrosis, tumour size, microvascular invasion and 2004 WHO histotype are independent predictors of disease-free and cancer-specific survival.

OBJECTIVE

To evaluate the clinicopathological features and outcomes of 56 patients with unclassified renal cell carcinoma (RCC) meeting 2004 World Health Organization diagnostic criteria.

PATIENTS AND METHODS

Urological pathology files of the participating institutions were reviewed and cases of unclassified RCC that met the inclusion criteria were retrieved. Nuclear grade, pT status, tumour size, regional lymph node involvement, distant metastases, coagulative tumour necrosis, mucin and sarcomatoid differentiation were evaluated in radical nephrectomy or nephron-sparing specimens. Significant factors in univariate analysis were then assessed by a multivariate analysis of independent prognostic factors using Cox proportional hazard regression analysis.

RESULTS

Fifty-six cases met the histological criteria for unclassified RCC. Thirty-four (61%) cases were categorized as unrecognizable cell type (mean overall survival 47 months; median 36 months), 20 (36%) as composites of recognized types (mean overall survival 36 months; median 26 months), and two (4%) (mean survival 16 months; median 16 months) as pure sarcomatoid morphology without recognizable epithelial elements. Cox multivariate analysis showed nuclear grade (P = 0.020), stage (P < 0.001), tumour coagulative necrosis (P = 0.018), tumour size (P < 0.001), microvascular invasion (P < 0.001) and tumour histotype (P = 0.028) to be independent predictors of disease-free survival, with tumour size being the most significant (hazard ratio [HR] 9.068, 95% confidence interval [CI] 3.231-25.453). Nuclear grade (P = 0.026), stage (P < 0.001), tumour coagulative necrosis (P < 0.001), tumour size (P = 0.044), microvascular invasion (P < 0.001), tumour recurrence after surgery (P < 0.001) and tumour histotype (P = 0.056) were independent predictors of cancer-specific survival, with tumour recurrence after surgery being the most significant (HR 14.713, 95% CI 5.329-40.622).

CONCLUSION

The prognosis of patients with unclassified RCC seems to be related to clinicopathological features known to be relevant in common forms of RCC.

Is the presence or absence of tumour necrosis a significant predictor of survival in renal cell cancer?

OBJECTIVE

Currently when renal cancer pathology is assessed the presence or absence of necrosis is simply reported. It has been suggested that a presence or absence response ignores heterogeneity and a classification based on the extent of necrosis involvement would aid prognostic value in cancer-specific survival. The aim of this study was to determine whether a quantitative assessment of tumour necrosis would provide additional prognostic information.

METHODS

We studied the pathological features and cancer-specific survival of 47 patients with renal cancer undergoing surgery with curative intent. A quantitative assessment of tumour necrosis was compared to the presence or absence of necrosis.

RESULTS

Tumour necrosis was present in 27 of 47 cases. A simple assessment of the presence or absence was not associated with cancer-specific survival (p = 0.052). When assessed quantitatively, tumour necrosis was associated with decreased cancer-specific survival (p < 0.001). A 2-tiered assessment, <25% and >25% involvement of necrosis, was further utilised and shown to predict cancer-specific survival (p < 0.001). On multivariate analysis, using this 2-tiered assessment of <25% and >25% involvement of necrosis was retained as a significant independent factor for cancer-specific survival (HR 11.84, 95% CI 3.81-36.75, p < 0.001).

CONCLUSION

A simple assessment of the presence/absence of tumour necrosis is reported to be a prognostic factor in renal cell cancer. In this study, the presence/absence was not shown to be a significant prognostic marker of cancer-specific survival. However, a more accurate quantitative assessment of tumour necrosis, whereby a 2-tiered response is still utilised, but basing this on <25% and >25% involvement of necrosis was statistically significant and independent in predicting cancer-specific survival.

Micro soft tissues visualization based on x-ray phase-contrast imaging

The current imaging methods have a limited ability to visualize microstructures of biological soft tissues. Small lesions cannot be detected at the early stage of the disease. Phase contrast imaging (PCI) is a novel non-invasive imaging technique that can provide high contrast images of soft tissues by the use of X-ray phase shift. It is a new choice in terms of non-invasively revealing soft tissue details. In this study, the lung and hepatic fibrosis models of mice and rats were used to investigate the ability of PCI in microstructures observation of soft tissues. Our results demonstrated that different liver fibrosis stages could be distinguished non-invasively by PCI. The three-dimensional morphology of a segment of blood vessel was constructed. Noteworthy, the blood clot inside the vessel was visualized in three dimensions which provided a precise description of vessel stenosis. Furthermore, the whole lung airways including the alveoli were obtained. We had specifically highlighted its use in the visualization and assessment of the alveoli. To our knowledge, this was the first time for non-invasive alveoli imaging using PCI. This finding may offer a new perspective on the diagnosis of respiratory disease. All the results confirmed that PCI will be a valuable tool in biological soft tissues imaging.

Obesity and microvascular invasion in hepatocellular carcinoma

BACKGROUND

We hypothesized that hepatocellular carcinoma (HCC) patients with higher Body Mass Index (BMI) might have more microvascular invasion (MVI) in their tumors.

METHODS

Records from 138 consecutive patients who underwent surgery at Columbia University Medical Center from January 1, 2002 to January 9, 2008 were evaluated.

RESULTS

40 patients (29%) had MVI, including 14% with BMI <25, 31% with BMI = 25-30, and 40% with BMI >30 (p = .05). However, only maximum alpha-fetoprotein was significantly associated with overall mortality in a Cox model.

CONCLUSIONS

MVI was associated with obesity. A better understanding of the mechanism of this association may lead to interventions for the treatment and prevention of HCC.

Noninvasive visualization of microvessels using diffraction enhanced imaging

The architecture of the vascular network is crucial because almost every disease alters the morphology of the blood vessel. Although existing imaging technique can provide vessel images, microvessels will not be discerned without the use of contrast agents. Furthermore, conventional imaging technique can only provide the outline of the vessels due to the restriction of spatial resolution. In this study, a novel imaging technique, diffraction enhanced imaging (DEI), is applied to the observation of microvessels in mouse hepatic fibrosis samples. With high spatial resolution and contrast of biological soft tissues, DEI is a non-invasive synchrotron-based imaging technique and does not require contrast agents. Particularly, this article highlights the exploration of the objects inside microvessels. A segment of blood vessel, which is obstructed by a blood clot, is under quantitative assessment and the result provides a precise description of vessel stenosis. Additionally, as one of the application of the diffraction enhanced imaging, blood stream simulation is carried out on the three-dimensional model of the vessel. It proves that this imaging technique has great value in evaluating hemodynamics and histopathology of microvascular diseases.

The Prognostic Factors for Patients with pT1a Renal Cell Carcinoma

Purpose

Although the prognosis of patients with pT1a stage renal cell carcinoma (RCC) is generally good, some of these patients show distant metastasis. In this study, we intended to identify the perioperative and pathologic prognostic factors for patients with pT1a stage RCC.

Materials and Methods

A total of 93 patients who were diagnosed with pT1aN0M0 RCC between January 1995 and December 2004 were included. All the patients underwent radical (n=63, 67.7%) or partial (n=30, 32.3%) nephrectomy by a single surgeon. Preoperative data [age, sex, body mass index (BMI), and the presence of symptoms], follow-up duration, surgical methods, and pathological parameters (tumor size, tumor location, histologic type, Fuhrman's nuclear grade and the presence of microvascular invasion, hemorrhage, necrosis, calcification, and a cystic component in the tumor) were retrospectively analyzed to identify which of these were prognostic factors for pT1a RCC.

Results

The patients' mean age was 55.0±11.4 years and the mean follow-up duration was 63.6±31.1 months. The 5-year cancer-specific survival rate and the 5-year recurrence- free survival rate were 100% and 88.1%, respectively. Nine patients (9.7%) showed distant metastasis, but local recurrence was not shown. Fuhrman's nuclear grade (p=0.040, OR=5.147), microvascular invasion (p=0.011, OR=13.500), and tumor necrosis (p<0.001, OR=26.000) had a significant impact on distant metastasis in the univariate analysis. The multivariate analysis subsequently showed that microvascular invasion (p=0.033, OR=17.947) and tumor necrosis (p=0.002, OR=15.922) were independent prognostic factors.

Conclusions

Microvascular invasion and tumor necrosis are the prognostic factors for patients with pT1a RCC.

The role of lymphovascular space invasion in renal cell carcinoma as a prognostic marker of survival after curative resection

OBJECTIVES

Lymphovascular invasion (LVI) correlates with adverse outcomes in numerous malignancies. However, its role in predicting outcomes in RCC is unclear. Herein, we evaluated what effect LVI had on metastasis free survival (MFS), disease-specific survival (DSS), and overall survival (OS) in patients with RCC treated with surgical excision.

METHODS

Eight hundred forty-one consecutive patients who underwent partial or radical nephrectomy from 1989 to 2004 were identified. Pathologic and gross features examined were LVI, subtype, Fuhrman grade, stage, and size. Age and gender were also analyzed. Slides were re-reviewed by a single pathologist (MS). Variables with P < 0.1 on univariate analysis were incorporated in a Cox proportional hazards multivariate model. MFS, DSS, and OS were described for patients with and without LVI using the Kaplan-Meier method, and compared with the log-rank test.

RESULTS

LVI was seen on H and E stained slides in 91 patients (11%); 120 (14%) developed metastatic disease, 91 (11%) died of RCC, and 306 (36%) died during a median follow-up of 61 months. While on univariate analysis, LVI was strongly associated with decreased MFS, DSS, and OS (P < 0.0001), on multivariate analysis, LVI was no longer statistically significant for MFS, DSS, and OS with a HR of 0.976 (95% CI: 0.583-1.63; P = 0.93), 0.96 (95% CI: 0.542-1.69; P = 0.88), and 1.24 (95% CI: 0.869-1.77; P = 0.24).

CONCLUSIONS

We found LVI to be associated with worse MFS, DSS, and OS on univariate analysis, but not on multivariate analysis for patients with nonmetastatic RCC. In contrast to previously reported studies, LVI may not be an independent prognostic variable in patients with localized RCC.

[Value of the postoperative Störkel score. Predict disease-free survival of patients with surgically resected renal cell carcinoma]

OBJECTIVE

To determine the value of clinical and pathological parameters defining the Störkel score in order to predict outcomes of patients with surgically treated renal cell carcinoma (RCC).

MATERIAL AND METHODS

A total of 834 consecutive patients having radical or partial nephrectomy were retrospectively reviewed. For each patient with RCC, the prognostic Störkel score was calculated according to the following variables: Robson stage, Thoenes nuclear grading, histological type, pattern of growth, and age. Based on the Störkel score, patients were divided into groups: those with good prognosis (GP), intermediate prognosis (IP), and poor prognosis (PP). Cancer-specific survival (CSS) and overall survival (OS) were estimated using the Kaplan-Meier method. The accuracy of prediction of CSS and OS with the Störkel score was analyzed using Kaplan-Meier analysis, proportional hazards regression, and graphic representation [(Kaplan-Meier curves, area under the curve (AUC)]. In 564 patients who were still alive, the median follow-up was 79 months (mean 84.8 months).

RESULTS

In the GP, IP, and PP groups, CSS after 8 years was 86.7%, 75.6%, and 13.7%, respectively (p<0.001). In the multiple analysis, only the Robson stage and Thoenes nuclear grading independently predicted CSS. Accordingly, the prognostic accuracy of the Störkel score (CSS prediction: AUC=0.744, 95% CI=0.70-0.79) was not better than with a reduced model that included the Robson stage and grading only (CSS prediction: AUC=0.765, 95%CI=0.72-0.81).

CONCLUSIONS

Of all parameters included in the Störkel score, only the Robson stage and nuclear grading are significant prognostic factors. Hence, we recommend an accordant modification of the score with additional variables.

Prognostic value of capsular invasion for localized clear-cell renal cell carcinoma

BACKGROUND

The impact of capsular invasion on the survival of patients undergoing surgery for renal cell carcinoma (RCC) has attracted little attention in the literature and remains controversial.

OBJECTIVES

To evaluate the value of capsular invasion, without perirenal fat invasion, on the prognosis of patients with localized clear-cell RCC.

DESIGN, SETTING, AND PARTICIPANTS

Between 1984 and 2007, we retrospectively reviewed the records of 317 consecutive patients with localized clear-cell RCC (pT1-T2N0M0) who underwent radical nephrectomy or nephron-sparing surgery at our institution. Overall, 299 patients were eligible for the study. We analyzed clinical (presentation and body mass index [BMI]) and pathologic (tumor size, Fuhrman nuclear grade, collecting system invasion, microvascular invasion, and capsular involvement) parameters.

MEASUREMENTS

Recurrence-free survival (RFS) and cancer-specific survival (CSS) were investigated using the Kaplan-Meier method, and the Cox regression model was used to determine the significant prognostic factors based on multivariate analysis.

RESULTS AND LIMITATIONS

Renal capsular invasion was observed in 106 of 299 patients (35.5%). Capsular invasion had a statistically significant association with age, symptomatic presentation, tumor diameter, pathologic stage, collecting system invasion, and microvascular invasion. The mean follow-up was 60.5 mo (range: 1-249). The 5-yr RFS and CSS rates for tumors with capsular invasion were significantly lower compared with rates for tumors without invasion (77.7% vs 92.3% and 85.5% vs 95.7%, respectively; p=0.0004). Multivariate analysis showed that BMI (hazard ratio [HR]=0.19), stage (HR=2.45), and capsular invasion (HR=3.36) were independent prognostic factors of disease recurrence. With respect to CSS, BMI (HR=0.20), tumor size (HR=1.13), and capsular invasion (HR=4.03) were the factors related to death. Nevertheless, we recognize that these findings may be limited by the study's retrospective, single-institution design.

CONCLUSIONS

Our findings suggest that capsular invasion is associated with poor survival in patients with localized clear-cell RCC.

Percentage of high-grade carcinoma as a prognostic indicator in patients with renal cell carcinoma

BACKGROUND

The prognostic value of Fuhrman nuclear grade for patients with renal cell carcinoma has been well-characterized. However, to the authors' knowledge, the prognostic significance of the amount of high-grade renal cell carcinoma has not been previously analyzed.

METHODS

The authors identified 898 consecutive renal cell carcinoma cases treated with nephrectomy between 1989 and 2003. Histopathologic features that were captured based on re-review of all slides included histologic type, pathologic stage, conventional Fuhrman grade, and percentage of Fuhrman grade 3 and 4 carcinoma, as ascertained by visual inspection of histologic slides. The clinical endpoints were metastasis-free survival, cancer-specific survival, and overall survival.

RESULTS

Kaplan-Meier analysis demonstrated that both conventional Fuhrman grading and the percentage of Fuhrman grade 3 and 4 carcinoma were highly correlated with all 3 measures of patient survival (P < .0001). The creation of 3 categories of the percentage of Fuhrman grade 3 and 4 carcinoma (0%, 1-50%, and 51-100%) generated distinctly separate survival curves. On Cox proportional hazards multivariate analysis, TNM stage, tumor size, and the percentage of Fuhrman grade 3 and 4 carcinoma were all found to be significantly associated with all 3 types of patient survival (all P values <.05).

CONCLUSIONS

The determination of the percentage of renal cell carcinoma that is 0%, 1% to 50%, or 51% to 100% high Fuhrman grade 3 and 4 is a simple and powerful measurement of patient outcome after surgery that provides additional prognostic information beyond stage, tumor size, and conventional Fuhrman grade. This prognostic information could be useful in the stratification of patients into prognostic groups for the development of more individualized follow-upschedules and for enrollment into clinical trials.

Combined expression of caveolin-1 and an activated AKT/mTOR pathway predicts reduced disease-free survival in clinically confined renal cell carcinoma

We previously reported that tumour-associated caveolin-1 is a potential biomarker in renal cell carcinoma (RCC), whose overexpression predicts metastasis following surgical resection for clinically confined disease. Much attention has recently focused on the AKT/mTOR pathway in a number of malignancies, including RCC. Since caveolin-1 and the AKT/mTOR signalling cascade are independently shown to be important regulators of tumour angiogenesis, we hypothesised that caveolin-1 interacts with the AKT/mTOR pathway to drive disease progression and metastasis in RCC. The aims of this study were to determine (i) the expression status of the activated AKT/mTOR pathway components (phosphorylated forms) in RCC and (ii) their prognostic value when combined with caveolin-1. Immunohistochemistry for caveolin-1, pAKT, pmTOR, pS6 and p4E-BP1 was performed on tissue microarrays from 174 clinically confined RCCs. Significantly decreased mean disease-free survival was observed when caveolin-1 was coexpressed with either pAKT (2.95 vs 6.14 years), pmTOR (3.17 vs 6.28 years), pS6 (1.45 vs 6.62 years) or p4E-BP1 (2.07 vs 6.09 years) than when neither or any one single biomarker was expressed alone. On multivariate analysis, the covariate of ‘caveolin-1/AKT’ (neither alone were influential covariates) was a significant influential indicator of poor disease-free survival with a hazard ratio of 2.13 (95% CI: 1.15–3.92), higher than that for vascular invasion. Tumours that coexpressed caveolin-1 and activated mTOR components were more likely to be larger, higher grade and to show vascular invasion. Our results provide the first clinical evidence that caveolin-1 cooperates with an activated AKT/mTOR pathway in cancer and may play an important role in disease progression. We conclude that evaluation of the ‘caveolin-1/AKT/mTOR axis’ in primary kidney tumours will identify subsets of RCC patients who require greater postoperative surveillance and more intensive treatment.

The chemokine receptor CXCR3 is an independent prognostic factor in patients with localized clear cell renal cell carcinoma

PURPOSE

Through its binding with interferon inducible angiostatic chemokines the chemokine receptor CXCR3 has an important role in regulating tumor mediating immunity, angiogenesis and metastatic spread. To evaluate its role in the biology of clear cell renal cell carcinoma we performed a tissue microarray based study.

MATERIALS AND METHODS

The tissue microarray comprised 154 patients who underwent nephrectomy for localized (N0M0) clear cell renal cell carcinoma at UCLA from 1989 to 2000. Immunohistochemical staining was evaluated by 2 anatomical pathologists who were blinded to outcome. The end point of this study was disease-free survival. Median followup was 5.9 years.

RESULTS

A total of 96% of the tumor specimens stained positive for CXCR3. The mean percent of cells staining positive was 68% (range 0 to 100%). CXCR3 expression was not associated with other common clinicopathological features, such as Eastern Cooperative Oncology Group performance status, T stage, Fuhrman grade, vascular invasion or sarcomatoid features. Patients with low CXCR3 expression (less than 30%) had a significantly worse prognosis than patients with high CXCR3 expression with a 5-year disease-free survival rate of 57% vs 82% (p = 0.009). Multivariate Cox regression analysis retained T stage, Eastern Cooperative Oncology Group performance status, sarcomatoid features and CXCR3 as independent prognostic factors.

CONCLUSIONS

CXCR3 is a novel molecular marker in patients with clear cell renal cell carcinoma. Its higher expression is an independent predictor of improved disease-free survival following nephrectomy for localized disease. Since CXCR3 is not associated with other clinicopathological prognostic factors, it may represent an ideal complementary molecular marker for identifying patients who are at higher risk for recurrence after nephrectomy.