Significance of conventional and new prognostic factors for locally confined renal cell carcinoma

Prognostic Biomarkers in Renal Cell Carcinoma: Relevance of DNA Ploidy in Predicting Disease-Related Survival

Objective

To investigate the prognostic value of DNA ploidy, Ki-67 index and p53 expression in relation to disease-related survival in a consecutive series of patients with renal cell carcinoma (RCC).

Material and methods

The study group consisted of 64 RCC patients treated by radical nephrectomy. Histological type, pathological staging and nuclear anaplasia were assessed according to the WHO classification, TNM system and Fuhrman grading criteria, respectively. Ploidy was determined by DNA flow cytometry using two sampling methods (frozen vs paraffin-embedded tissue). Ki-67 and p53 were evaluated by immunohistochemistry techniques using two cutoff points (10% vs mean value) for staining interpretation. Kaplan-Meier and Cox regression analyses were used for prognostic evaluation.

Results

Thirty-one tumors (48.4%) showed DNA diploidy and 33 (51.6%) were DNA aneuploid. Concordance between both ploidy measurement methods was found in 85.5% of cases (p=0.0455). The mean values for Ki-67 and p53 immunostaining were 3.65% (0–23.5%) and 5.90% (0–55.9%), respectively. DNA ploidy significantly correlated with staging, tumor size (pT), nuclear grading, and Ki-67 (mean value cutoff). Ki-67 (10% cutoff) correlated with staging and pT, while p53 (mean value cutoff) was associated with Ki-67 (mean value cutoff). There were significant differences between survival curves for pathological stage, pT, nuclear grade, ploidy, Ki-67 (both cutoffs), and p53 (10% cutoff). By univariate regression analysis, stage III and stage IV, pT3, aneuploidy, high Ki-67 (both cutoffs), and p53 overexpression (10% cutoff) showed significant correlations with worse disease-related survival. In addition, DNA aneuploidy significantly correlated with poor prognosis within stages I/II (p=0.0355) and stages III/IV (p=0.0138) of the disease.

Conclusion

The results indicate that DNA ploidy has relevant prognostic value in RCC, adding useful information to the classic histopathological indicators of clinical outcome.

MTBP is overexpressed in triple-negative breast cancer and contributes to its growth and survival

Triple-negative breast cancer (TNBC) is a clinically aggressive subtype of breast cancer commonly resistant to therapeutics that have been successful in increasing survival in patients with estrogen receptor-positive (ER(+)) and HER2(+) breast cancer. As such, identifying factors that contribute to poor patient outcomes and mediate the growth and survival of TNBC cells remain important areas of investigation. MTBP (MDM2-binding protein), a gene linked to cellular proliferation and a transcriptional target of the MYC oncogene, is overexpressed in human malignancies, yet its contribution to cancer remains unresolved. Evaluation of mRNA expression and copy number variation data from The Cancer Genome Atlas (TCGA) revealed that MTBP is commonly overexpressed in breast cancer and 19% show amplification of MTBP. Increased transcript or gene amplification of MTBP significantly correlated with reduced breast cancer patient survival. Further analysis revealed that while MTBP mRNA is overexpressed in both ER(+) and HER2(+) breast cancers, its expression is highest in TNBC. MTBP mRNA and protein levels were also significantly elevated in a panel of human TNBC cell lines. Knockdown of MTBP in TNBC cells induced apoptosis and significantly reduced TNBC cell growth and soft agar colony formation, which was rescued by expression of shRNA-resistant Mtbp. Notably, inducible knockdown of MTBP expression significantly impaired TNBC tumor growth, in vivo, including in established tumors. Thus, these data emphasize that MTBP is important for the growth and survival of TNBC and warrants further investigation as a potential novel therapeutic target.

IMPLICATIONS

MTBP significantly contributes to breast cancer survival and is a potential novel therapeutic target in TNBC.

Prognostic biomarkers in renal cell carcinoma

A hallmark of renal cell carcinoma is its variable prognosis. Surgical resection of primary renal cell carcinoma can be curative when the disease is localized. However, approximately 20% of patients with early stages of localized renal cell carcinomas subsequently develop metastasis after the primary tumor is removed. The median survival for patients with metastatic disease is approximately 13 months. Therefore, there is a great need for biomarkers to predict metastasis and prognosis. Many prognostic biomarkers were studied in the past decade. In recent years, several promising biomarkers, including CAIX, B7-H1 and IMP3, have also been identified by large retrospective studies. Further validation of these biomarkers is essential to transfer the research data into clinical practice. Eventually, an outcome prediction model with biomarkers, staging system and other risk factors will identify high-risk patients with likelihood of progression and formulate different follow-up protocols or systematic treatments for these patients.

Ki67 is an independent predictor of oncological outcomes in patients with localized clear-cell renal cell carcinoma

OBJECTIVE

To validate the impact of Ki67 expression on oncological outcomes of patients treated for clinically localized clear-cell renal cell carcinoma (ccRCC).

PATIENTS AND METHODS

Immunohistochemistry for Ki67 was performed on tissue microarray constructs of patients treated with radical or partial nephrectomy for clinically localized (M0) ccRCC and Ki67 expression >10% was considered abnormal. Clinical and pathological data elements were entered into an institutional review board-approved database. The Kaplan-Meier method and Cox regression models were used to analyse disease-free survival (DFS) and cancer-specific survival (CSS) probabilities.

RESULTS

Of 401 patients, 59.6% were males. The median (range) age was 58 (17-85) years, follow-up was 22 (0-150) months and time to death was 27 (0-150) months. A total of 20.2% of patients had advanced stage (pT3-T4) and 31% had advanced grade (3-4) disease. Abnormal expression of Ki67 was seen in 6.5% of our cohort and was associated with adverse pathological features (P < 0.05). Patients with high expression of Ki67 were found to have 5-year DFS and CSS rates of 67 and 84%, respectively, vs 87 and 95%, respectively, in those with normal expression (P < 0.001 and P < 0.05, respectively). In multivariable analyses, adjusting for stage and grade, abnormal Ki67 expression was an independent predictor of DFS (hazard ratio [HR] 3.77, P = 0.011, 95% confidence interval [CI] 1.35-10.52), but not of CSS (HR 3.51 P = 0.137, 95% CI 0.671-18.35).

CONCLUSIONS

Our findings support the role of Ki67 as a powerful independent predictor of inferior oncological outcomes in patients with ccRCC. Further prospective studies are needed to determine the clinical applicability of these findings.

Collecting system invasion and Fuhrman grade but not tumor size facilitate prognostic stratification of patients with pT2 renal cell carcinoma

PURPOSE

The 7th edition of TNM for renal cell carcinoma introduced a subdivision of pT2 tumors at a 10 cm cutoff. In the present multicenter study the influence of tumor size as well as further clinical and histopathological parameters on cancer specific survival in patients with pT2 tumors was evaluated.

MATERIALS AND METHODS

A total of 670 consecutive patients with pT2 tumors (10.4%) of 6,442 surgically treated patients with all tumor stages were pooled (mean followup 71.4 months). Tumors were reclassified according to the current TNM classification, and subdivided in stages pT2a and pT2b. Cancer specific survival was analyzed using the Kaplan-Meier method, and univariable and multivariable analyses were used to assess the influence of several parameters on survival.

RESULTS

Tumor size continuously applied and subdivided at 10 cm or alternative cutoffs did not significantly influence cancer specific survival. In addition to N/M stage, Fuhrman grade and collecting system invasion also had an independent influence on survival. Integration of a dichotomous variable subsuming Fuhrman grade and collecting system invasion (grade 3/4 and/or collecting system invasion present vs grade 1/2 and collecting system invasion absent) into multivariate models including established prognostic parameters resulted in improvement of predictive abilities by 11% (HR 2.3, p <0.001) for all pT2 cases and 151% (HR 3.1, p <0.001) for stage pT2N0M0 cases.

CONCLUSIONS

Tumor size did not have a significant influence on cancer specific survival in pT2 tumors, neither continuously applied nor based on various cutoff values. To enhance prognostic discrimination, multifactorial staging systems including pathological features should be implemented. The prognostic relevance of the variable subsuming Fuhrman grade and collecting system invasion should be considered for future evaluation.

Overexpression of DLC-1 induces cell apoptosis and proliferation inhibition in the renal cell carcinoma

The lack of effective anti-tumor therapy for renal cell carcinoma (RCC) has stimulated the search for novel target whose inhibition could block tumorigenesis. Recently, reduced DLC-1 has been shown to be associated with aggressive and highly metastatic renal cell carcinoma. In this study, the biological role of DLC-1 on cell growth, migration and cell cycle progression in RCC cells was investigated. Over-expression of DLC-1 was associated with a marked inhibition of cell growth (P<0.01). The inhibitory effect was partly due to the induction of apoptosis and cell cycle arrest in G(0)/G(1) accompanied by up-regulation of the intracellular signal proteins of p27 and down-regulation of cyclin D1 and cyclin E. Furthermore, DLC-1 induced FAK dephosphorylation of focal adhesion proteins inhibited cell migration (P<0.05). Decreased DLC-1 expression strongly correlated with proliferative activity, as indicated by the elevated levels of Ki67. Restoration of DLC-1 expression in RCC cells led to Bcl-2 and caspase-3 mediated apoptosis as well as attenuated the ability of the cells to form RCC tumors in athymic nude mice (P<0.05). Taken together, these results suggest that DLC-1 plays a crucial role in signal transduction pathway regulating the cell proliferation, migration, and carcinogenesis of human RCC.

Diagnostic and prognostic molecular markers in renal cell carcinoma

PURPOSE

We reviewed the contemporary literature on molecular biomarkers in renal cell carcinoma and their prognostic significance.

MATERIALS AND METHODS

Articles published during 1981 to 2007 in English on renal cell carcinoma were surveyed using the MEDLINE/PubMed database. The subject headings included were genetics, biomarkers, prognosis and risk models of renal cell carcinoma. We present a synthesis of currently known renal cell carcinoma biomarkers at various stages of development and their clinical significance, and prognostic nomograms incorporating biomarkers.

RESULTS

The beneficiary role of biomarkers in renal cell carcinoma is challenged by the relatively low prevalence of the disease. Even if a biomarker for renal cell carcinoma had 100% sensitivity and 99.4% specificity, the positive predictive value of the marker in men older than 65 years would be only 10%. Several biomarkers are being investigated in renal cell carcinoma, of which many relate to pathogenic molecular changes that are currently therapeutic targets. Carbonic anhydrase IX is a von Hippel-Lindau mediated enzyme that is expressed in most renal cell carcinoma cases. High (greater than 85%) expression of this marker indicates favorable prognosis and may predict the response to interleukin-2 therapy. B7-H1 expression in renal cell carcinoma cells/lymphocytes may indicate worse survival, possibly through impaired host antitumor immunity. Prognostic nomograms incorporating clinical variables and molecular markers to refine the prediction of treatment outcomes are in active development and await prospective clinical validation.

CONCLUSIONS

Several renal cell carcinoma molecular markers appear promising to refine the prognosis and prediction of localized, advanced or metastatic renal cell carcinoma. Currently carbonic anhydrase IX is the best studied and promising marker. Prospective, multicenter clinical validation aimed at the practical clinical usefulness of renal cell carcinoma biomarkers is warranted.

Impact of discordant radiologic and pathologic tumor size on renal cancer staging

OBJECTIVES

To determine whether the discrepancy in the radiologic and pathologic size of renal cell carcinoma influences the final cancer stage.

METHODS

Renal masses resected from December 1999 to September 2004 were identified using a pathologic database and compared by surgical accession number to an existing clinical renal tumor database to identify those T1 and T2 tumors for which radiologic and pathologic data were available. The tumor histologic features, maximal pathologic diameter, and maximal radiologic diameter were recorded. The percentage of tumor size reduction was then calculated using these data.

RESULTS

Of the 236 renal cancers evaluated, 52% had regressed in size when comparing the pathologic and radiologic sizes. When stratified by histologic subtype, clear cell tumors regressed more often and to a greater degree than those that were chromophobe or papillary. Also, 15 organ-confined tumors were downstaged when comparing the maximal radiologic diameter and the maximal pathologic diameter, and 13 of these were clear cell tumors.

CONCLUSIONS

A reduction in kidney tumor size is commonly observed at surgical resection because of a loss of blood flow to the tumor. This tumor size reduction has an impact on the final pathologic stage in organ-confined tumors for which size is the only criterion. The greatest tumor size reduction, and most frequent downstaging, was observed for conventional (clear cell) tumors. We believe this may explain, in part, the worse stage-stratified outcomes for clear cell tumors compared with other tumor types. We propose that renal cancer staging should be determined from accurate measurement of the radiologic size, rather than the pathologic size.

Evaluación del estudio pT3a de la actual clasificación TNM del cáncer renal

OBJECTIVE

We assessed the prognostic value of a stage pT3a diagnosis based on perirrenal fat infiltration.

MATERIAL AND METHODS

A series of 300 patients diagnosed of renal cell carcinoma (CCR) between 1992 and 2001 were retrospectively analyzed. Focusing on pT3a tumors as defined by perirrenal fat infiltration, a group of 92 patients (91,08%) regardless lymph node involvement (Nall) were included. Patients with distant metastases were excluded. In patients with pT3a Nall M0 tumors, tumour size was a significant parameter predicting survival. The most significant cut-off value for tumor size based on ROC curve was 5,5 cm. Therefore two groups were defined (up to 5,5 cm or greater than 5,5 cm) and actuarial survival were compared between both groups.

RESULTS

No significant differences were found comparing actuarial survival of selected pT3a and tumour size less than 5,5 cm with pT1 and pT2 tumors. After classifying selected pT3a less than 5,5 cm as pT1, multivariate analysis showed no differences regarding to prognostic variables before and after classification. Subsequently multivariate analysis showed that modified T stage was an independent significant predictor of cancer specific actuarial survival.

CONCLUSIONS

Perirrenal fat infiltration in renal cell carcinoma should not be used to assign T category. In our series grading tumors pT3a lesser than 5,5 cm as pT1/pT2 TNM stage does not affect their prognostic value.

Mcm2, Geminin, and KI67 define proliferative state and are prognostic markers in renal cell carcinoma

PURPOSE

The origin licensing factors minichromosome maintenance 2 (Mcm2) and Geminin have recently been identified as critical regulators of growth and differentiation. Here we have investigated the regulation of these licensing factors together with Ki67 to further elucidate the cell cycle kinetics of renal cell carcinoma (RCC). Furthermore, we have examined the role of Ki67, Mcm2, and Geminin in disease-free survival after nephrectomy in patients with localized RCC.

EXPERIMENTAL DESIGN

Tissue sections from 176 radical nephrectomy specimens were immunohistochemically stained with Mcm2, Geminin, and Ki67 antibodies. Labeling indices (LI) for these markers were compared with clinicopathologic parameters (median follow-up 44 months).

RESULTS

In RCC, Mcm2 is expressed at much higher levels than Ki-67 and Geminin, respectively [medians 41.6%, 7.3%, and 3.5% (P < 0.001)] and was most closely linked to tumor grade (P < 0.001). For each marker, Kaplan-Meier survival curves provided strong evidence that increased expression is associated with reduced disease-free survival time (P < 0.001). Additionally, an Mcm2-Ki67 LI identified a unique licensed but nonproliferating population of tumor cells that increased significantly with tumor grade (P = 0.004) and was also of prognostic value (P = 0.01). On multivariate analysis, grade, vascular invasion, capsular invasion, Ki67 LI >12%, and age were found to be independent prognostic markers.

CONCLUSIONS

Although Ki67 is identified as an independent prognostic marker, semiquantitative assessment is difficult due to the very low proliferative fraction identified by this marker. In contrast, Mcm2 identifies an increased growth fraction that is closely linked to grade, provides prognostic information, and is amenable to semiquantitative analysis in routine pathologic assessment.

Biochemical and molecular markers in renal cell carcinoma: an update and future prospects

Cancer is a big problem in the developed world as well as in developing countries. Renal cell carcinoma (RCC) accounts for approximately 3% of adult malignancies and 90-95% of neoplasms arising from the kidney. RCC is more common in men than in women (2:1), and it most often occurs in patients between the ages of 50-70 years. In all cancers the cancerous cells release particular kind of proteins (called tumour markers) and blood tests are used to detect the presence of these markers. These tumour markers nowadays are an area of interest for oncologists who search for a possible solution in the detection and treatment of RCC. Different kinds of biochemical and molecular markers such as ferritin, MN/CA9, apoptotic index, p53, IL-2, gamma-enolase, CD44, CD95, chromosome instability and loss of heterozygosity have been tested in RCC, but so far no marker fulfils one or the other criteria to be considered as an ideal marker for RCC. This review gives basic and updated information about the different kinds of biomarkers studied in RCC and about the role implementation of genomics and proteomics in RCC.

pT2 CLASSIFICATION FOR RENAL CELL CARCINOMA. CAN ITS ACCURACY BE IMPROVED?

PURPOSE

The 2002 tumor classification for renal cell carcinoma (RCC) classifies pT2 tumors as more than 7 cm in greatest dimension, limited to the kidney. In this study we determined whether a size cutoff point exists within pT2 tumors and whether such subclassification would further improve the accuracy of the current tumor classification.

MATERIALS AND METHODS

We studied 544 patients with unilateral, sporadic pT2 RCC treated with radical nephrectomy or nephron sparing surgery between 1970 and 2000. The association of tumor size with death from RCC was examined using martingale residuals from a Cox proportional hazards regression model to determine the optimal size cutoff point.

RESULTS

There were 204 deaths from RCC a median of 3.8 years following nephrectomy. Univariately tumor size was significantly associated with death from RCC (risk ratio 1.08, 95% CI 1.04 to 1.13, p <0.001). A scatterplot of tumor size vs expected risk of death per patient suggested that a cutoff point between 9 and 10 cm was appropriate. When adjusted for regional lymph node involvement and distant metastases, the 10 cm cutoff point performed better than the 9 cm point (risk ratio 1.42, 95% CI 1.07 to 1.90, p = 0.017 vs 1.22, 95% 0.86 to 1.72, p = 0.268). Therefore, we propose using a 10 cm cutoff point to subclassify patients into pT2a and pT2b.

CONCLUSIONS

Our data suggest that the prognostic accuracy of the 2002 pT2 tumor classification can be further improved by subclassifying patients with tumors greater than 7 and less than 10 cm into a pT2a category, and those with tumors 10 cm or greater into a pT2b category.

Costimulatory B7-H1 in renal cell carcinoma patients: Indicator of tumor aggressiveness and potential therapeutic target

Expression of B7-H1, a costimulating glycoprotein in the B7 family, is normally restricted to macrophage-lineage cells, providing a potential costimulatory signal source for regulation of T cell activation. In contrast, aberrant expression of B7-H1 by tumor cells has been implicated in impairment of T cell function and survival, resulting in defective host antitumoral immunity. The relationship between tumor-associated B7-H1 and clinical cancer progression is unknown. Herein, we report B7-H1 expression by both renal cell carcinoma (RCC) tumors of the kidney and RCC tumor-infiltrating lymphocytes. In addition, our analysis of 196 clinical specimens reveals that patients harboring high intratumoral expression levels of B7-H1, contributed by tumor cells alone, lymphocytes alone, or tumor and/or lymphocytes combined, exhibit aggressive tumors and are at markedly increased risk of death from RCC. In fact, patients with high tumor and/or lymphocyte B7-H1 levels are 4.5 times more likely to die from their cancer than patients exhibiting low levels of B7-H1 expression (risk ratio 4.53; 95% confidence interval 1.94-10.56; P < 0.001.) Thus, our study suggests a previously undescribed mechanism whereby RCC may impair host immunity to foster tumor progression. B7-H1 may prove useful as a prognostic variable for RCC patients both pre- and posttreatment. In addition, B7-H1 may represent a promising target to facilitate more favorable responses in patients who require immunotherapy for treatment of advanced RCC.

Neoplasm Staging and Organ-Confined Renal Cell Carcinoma: A Systematic Review

OBJECTIVES

Several TNM staging system editions were published over the years for renal cell carcinoma (RCC). Using a search strategy similar to the one used by the TNM process Subcommittee for "literature watch", we searched MEDLINE with the intent to critically analyze literature concerning the different TNM editions and the data regarding the optimal breakpoints to substratify localized RCC.

MATERIAL AND METHODS

The electronic search was conducted as follows: "Neoplasm staging" [MeSH] AND "Carcinoma, Renal Cell" [MeSH]. At the end of a process of abstract analysis performed separately by three of the authors, 34 papers were included in the systematic review.

RESULTS

All the 34 selected papers were retrospective studies. According to the 1987 version of TNM classification, no paper showed statistically significant cancer-specific survival probability differences between stage I and stage II RCC. According to the 1997 TNM version, the results were controversial. While a few papers found significantly different cancer-specific survival rates between stage I and stage II RCC, several others failed to do so. With the aim to stratify patients with localized RCC, most of the papers proposed an ideal breakpoint ranging from 4.5 to 5.5 cm.

CONCLUSION

This literature review highlighted that a correct definition of the staging of organ-confined RCC was far from being achieved and provided an appropriate synopsis of the available data for further update of the TNM staging system.

The superior prognostic value of humoral factors compared with molecular proliferation markers in renal cell carcinoma

BACKGROUND

The American Joint Committee on Cancer and the Union Internationale Contre le Cancer have acknowledged routine laboratory parameters, such as serum calcium, alkaline phosphatase, hemoglobin, and the erythrocyte sedimentation rate (ESR), as predictors of survival in patients with renal cell carcinoma. The predictive value of these parameters compared with proliferation markers, such as Ki-67, proliferating cell nuclear antigen (PCNA), topoisomerase II-alpha, and p100, has not been determined.

METHODS

Forty-eight consecutive patients who underwent nephrectomy for nonmetastatic renal cell carcinoma between 1990 and 1994 were observed up to 120 months postoperatively. Ten of 48 patients developed tumor progression 6-69 months after surgery. Routine preoperative laboratory parameters as well as tumor-specific data were assessed. Findings were compared with tumor proliferation indices, which were obtained by immunohistochemical staining for nuclear antigens Ki-67, PCNA, topoisomerase II-alpha, and p100 in paraffin embedded tumor tissue.

RESULTS

Univariate and multivariate statistical analyses demonstrated superiority of routine laboratory values compared with tumor proliferation indices in predicting progression-free survival and disease-specific death. The best predictor after tumor size and symptomatic presentation was ESR (P < 0.0001), with ESR values > 70 mm at 2 hours indicating a significantly poorer prognosis. Only the proliferation marker Ki-67 reached univariate significance at a threshold of 7%.

CONCLUSIONS

Routine laboratory parameters, such as alkaline phosphatase, lactate dehydrogenase, thrombocyte count, and especially ESR, provided superior long-term prognostic information for patients with nonmetastatic renal cell carcinoma compared with the molecular tumor proliferation markers Ki-67, PCNA, topoisomerase II-alpha, and p100.

Prognostic value of carbonic anhydrase IX and KI67 as predictors of survival for renal clear cell carcinoma

PURPOSE

The natural history of renal cell carcinoma (RCC) is complex and not entirely explained by conventional prognostic factors. In this study we evaluated the prognostic value of carbonic anhydrase IX (CAIX) and Ki67 to predict survival in RCC.

MATERIALS AND METHODS

Immunohistochemical analysis using a CAIX and a Ki67 monoclonal antibody was performed on tissue microarrays constructed from paraffin embedded specimens from 224 patients treated with nephrectomy for clear cell renal carcinoma. CAIX and Ki67 staining were correlated with clinical factors, pathological features and survival. Median followup was 34 months (range 0.3 to 117) and disease specific survival was the primary end point assessed.

RESULTS

Univariate statistical analysis showed that high Ki67 staining and low CAIX staining correlated significantly with poor median survival (21 months, p < 0.001 and 22 months, p = 0.011, respectively). Each marker was highly significant for stratifying patient groups defined by T stage, Fuhrman grade, nodal status, metastatic status and performance status. On multivariate analysis CAIX and Ki67 were significant predictors of survival with an HR of 1.78 (p = 0.014) and 1.75 (p = 0.009), respectively. Although CAIX and Ki67 staining were inversely correlated (p = 0.009), Ki67 significantly substratified patient subgroups defined by high or low CAIX staining (p = 0.001 and 0.003, respectively). When Ki67 and CAIX were combined into a single parameter, RCC tumors could be stratified into low, intermediate and high risk groups with a median survival of greater than 101, 31 and 9 months, respectively (p <0.001). On multivariate analysis the combined parameter consisting of Ki67 and CAIX was a significant predictor of survival (p <0.001) and it was able to displace histological grade.

CONCLUSIONS

Ki67and CAIX are useful prognostic biomarkers for RCC that improve the survival prediction and classification of kidney cancer.

Current staging of renal cell carcinoma

Most (>80%) cancers involving the kidney are renal cell carcinoma (RCC). One third of patients diagnosed with kidney cancer have evidence of metastatic disease at the time of diagnosis, and as many as half of patients treated for localized disease eventually relapse. As is true for any other malignancy, one must determine which tumor features, patient factors, and laboratory techniques will provide diagnostic and prognostic information for patients with RCC. This article focuses on the history and rationale of the current staging systems for RCC as well as the potential for improvements by the addition of other clinical, pathologic, and molecular prognostic markers.

Correlation of Ki-67 and gelsolin expression to clinical outcome in renal clear cell carcinoma

OBJECTIVES

To analyze the expression levels of Ki-67 and gelsolin in renal cell carcinoma (RCC) and determine their prognostic value in association with other clinicopathologic factors using tissue microarray technology. Histologic nuclear grade, performance status, and clinical stage are important prognostic factors in RCC. Because patients with tumors of similar grade, performance status, and stage may show a wide variation in biologic behavior and clinical outcome, additional biomarkers for RCC are needed to provide further prognostic information and possibly offer insight into the mechanisms of the disease.

METHODS

Using a renal cancer tissue microarray, we correlated the expression of Ki-67, a marker of cell proliferation, and gelsolin, an actin-binding protein, with grade, stage, and survival in patients with clear cell RCC.

RESULTS

In Cox multivariate regression analysis, stage (pT) was the most significant predictor of cancer-specific survival (P <0.0001), followed by Ki-67 (P = 0.0216). In univariate analysis, increased Ki-67 expression predicted poor cancer-specific survival (P = 0.0006) when a cutoff value for Ki-67 staining was applied. In patients with grade 2 tumors, increased Ki-67 expression and decreased gelsolin expression in the same tumor was suggestive of poor cancer-specific survival (P = 0.0507).

CONCLUSIONS

Our findings support the utility of Ki-67 as a prognostic biomarker for RCC and suggest a role for gelsolin in renal carcinogenesis.

[Review of cut-off points between stages T1 and T2 in the 1997 TNM classification of renal carcinoma]

OBJECTIVE

We retrospectively review the patients treated at our institution for renal cell carcinoma (RCC). We compare the patients classified in TNM state T1N0M0 in the 1997 revision with the 1992 one in order to determine survival differences. We divide patients in three size related groups and compare its survival rates.

MATERIAL AND METHODS

We review 168 surgically treated patients. 72 of them were classified into T1N0M0 stage. We compare cancer-free survival in patients included in 1997 and 1992 T1 stage. We divide patients in three groups: 1-3 cm, 3-5 cm, 5-7 cm and compare respective cancer-free survival.

RESULTS

There is a survival difference between T1(1997)-T2(1992) (p = 0.478). There is an inferior survival in size group 5-7 cm compared with 1-3 cm and 3-5 cm ones (p = 0.02/0.0465).

CONCLUSIONS

In our patients, 1997 revision of T1 size supposes a descent of cancer-free survival compared with 1992 one. We consider a better stage limit under 5 cm, instead of actual 7 cm.

Prognostic factors of renal cell carcinoma

PURPOSE

Determination of prognostic factors is essential for the management of renal cell carcinoma. Stage, histological grade and type, and performance status are now well known and commonly used. During the last decade numerous predictors of patient outcome were tested. This review summarizes the most important studies, explores and compares the results, and tries to respond to the question, "Today, what do we expect of clinical, molecular and genetic factors concerning survival of patients with renal cell carcinoma?"

MATERIALS AND METHODS

Based on MEDLINE literature searches we comprehensively reviewed the literature on the prognostic factors associated with the tumor, the patient and the treatment.

RESULTS

During the last decades numerous factors have been studied but few of them maintained independent significance in terms of overall survival as assessed by multivariate analysis. Results are more often controversial from one series to another. No known molecular or cytogenetic tumor marker has been identified to help diagnose, manage or confirm renal cell carcinoma remission, progression or relapse.

CONCLUSIONS

The classical prognostic factors remain histological grade, histological type, performance status, patient age, number and location(s) of metastatic sites, time to appearance of metastases and prior nephrectomy. The only striking advancement during the last few years has been the proven contribution of radical nephrectomy for metastatic disease in patients with good performance status.

[Assessment of the basal membrane status as prognostic factor in renal carcinoma]

OBJECTIVES

To know the basal membrane (BM) integrity in renal cell carcinoma (RC) and its importance as prognostic factor.

MATERIAL AND METHODS

73 patients with RC were selected. Immunohistochemistry with monoclonal antibodies against basal proteins laminin and collagen IV was performed. Percentage for BM fragmentation in the whole tumour was considered taking 75% as cut off.

RESULTS

Follow-up was 6.3 +/- 4.3 years and 27 patients progressed. Correlation between laminin and collagen IV was significative (p = 0.000). A BM fragmentation expressed with laminin bigger than 75% was related to tumoural symptoms (p = 0.019), worse grade (p = 0.004) and necrosis in more than 10% of the tumour (p = 0.000). Fragmentation observed with collagen IV was associated to tumours greater than 7 cm (p = 0.014). Those patients whose tumours displayed more than 75% of BM fragmentation, measured with collagen IV, presented worse survival (p = 0.042). A similar trend was observed in the case of laminin, but it did not reach statistic significance (p = 0.119). In the unvariated analysis grade III-IV, more than 10% of necrosis within the tumour, tumoural symptoms and BM fragmentation bigger than 75% measured with collagen IV were prognostic, while only grade and necrosis did so in the multivariate analysis.

CONCLUSIONS

Collagen IV and laminin represent nicely, with a similar expression pattern, the BM fragmentation in RC. Within a battery of immunohistochemical markers to study RC at least one of them should be included because their prognostic implication.

Mathematical model to predict individual survival for patients with renal cell carcinoma

PURPOSE

To develop a multivariate model and mathematical formula capable of calculating personalized survival for renal cell carcinoma (RCC) patients with clinically available variables.

PATIENTS AND METHODS

A total of 477 patients out of 661 undergoing nephrectomy at the University of California Los Angeles between 1989 and 1999 were eligible for evaluation and formed the analyzed cohort for this retrospective study. Time to death was the primary end point assessed. Univariate analysis for 14 to 20 variables was conducted, followed by a multivariate Cox analysis. The variables that provided independent information as to the time of death for metastatic and nonmetastatic patients were coded and incorporated into a function based on the Nadas equation principle.

RESULTS

For nonmetastatic patients, the significant variables in the multivariate analysis were Fuhrman's grade and Eastern Cooperative Oncology Group performance status. For the metastatic patients, Fuhrman's grade, 1997 classification T stage, number of symptoms, nodal involvement, and immunotherapy were independent predictors for survival. These variables, based on the Cox multivariate regression model, were implanted into an exponential Nadas equation. The expected survival predicted by use of the Nadas equations faithfully describes the actual survival based on Kaplan-Meier curves.

CONCLUSION

We have developed mathematical equations for estimating survival after radical nephrectomy for RCC. The resulting formulas are capable of better tailoring survival estimates for a specific patient and are based on widely accepted clinical prognostic variables. On validation with external data, this type of representation can be used as a tool for the determination of personalized prognosis and may be useful for patient education and counseling.

Proliferative activity, angiogenesis and nuclear morphometry in renal cell carcinoma

BACKGROUND

Prognostic parameters other than tumor stage and grade are essential for renal cell carcinoma (RCC) patients. This study was undertaken to determine the usefulness of cellular proliferation, angiogenesis and nuclear morphometry in predicting the biological aggressiveness of RCC.

METHODS

Surgical specimens of 70 patients with RCC were investigated by conventional histology, Ki-67 immunostaining and stereological assessment of angiogenesis and mean nuclear volume.

RESULTS

There was no difference in disease-specific survival with respect to sex, age and histopathological type (except sarcomatoid and other types). The survival was significantly lower and the chance of metastases was higher in the group with higher proliferative activity (P=0.007). There was no relation between angiogenesis, mean nuclear volume, stage and survival. There was a significant relation between both Fuhrman and WHO grades, tumor stage and survival. Histopathological type, grade, angiogenesis and mean nuclear volume failed to predict recurrences and/or metastases. In multivariate analysis, only TNM stage and proliferative activity were found to be independent prognostic factors.

CONCLUSIONS

In addition to tumor grade and stage, proliferative activity of a given RCC may have the potential to identify patients with an impaired prognosis.

The changing natural history of renal cell carcinoma

PURPOSE

Our understanding of the natural history of renal cell carcinoma, the role of nephrectomy, the benefits of immunotherapy and the possibilities of new technologies are evolving and being integrated with advances in classification and staging. We reviewed the relevant literature to clarify these pertinent questions and provide a current review of the changes in the epidemiology, treatment and prognosis of patients with renal cell carcinoma.

MATERIALS AND METHODS

We comprehensively reviewed the peer reviewed literature on the current management of and results of treatment for renal cell carcinoma.

RESULTS

The incidence of and mortality from renal cell carcinoma have continuously increased during the last 50 years. Despite this increase in the number of new patients and consequently the number of deaths yearly the percent of those surviving for 5 years has notably improved. Factors related to improved survival include advances in renal imaging, earlier diagnosis, improved staging, better understanding of prognostic indicators, refinement in surgical technique and the introduction of immunotherapy approaches for advanced disease.

CONCLUSIONS

Currently patients with localized and metastatic renal cell carcinoma have had improvements in outlook and the therapeutic options available have expanded.

The changing natural history of renal cell carcinoma

PURPOSE

Our understanding of the natural history of renal cell carcinoma, the role of nephrectomy, the benefits of immunotherapy and the possibilities of new technologies are evolving and being integrated with advances in classification and staging. We reviewed the relevant literature to clarify these pertinent questions and provide a current review of the changes in the epidemiology, treatment and prognosis of patients with renal cell carcinoma.

MATERIALS AND METHODS

We comprehensively reviewed the peer reviewed literature on the current management of and results of treatment for renal cell carcinoma.

RESULTS

The incidence of and mortality from renal cell carcinoma have continuously increased during the last 50 years. Despite this increase in the number of new patients and consequently the number of deaths yearly the percent of those surviving for 5 years has notably improved. Factors related to improved survival include advances in renal imaging, earlier diagnosis, improved staging, better understanding of prognostic indicators, refinement in surgical technique and the introduction of immunotherapy approaches for advanced disease.

CONCLUSIONS

Currently patients with localized and metastatic renal cell carcinoma have had improvements in outlook and the therapeutic options available have expanded.

Morphologic typing of papillary renal cell carcinoma: comparison of growth kinetics and patient survival in 66 cases

Whereas papillary renal cell carcinoma is now established as a subtype of renal cell neoplasia, division of these tumors into 2 distinctive morphotypes has been proposed. Type 1 tumors have cells with scanty pale cytoplasm arranged in a single layer on the basement membrane of papillary cores. In these tumors, psammoma bodies and foamy macrophages are frequently seen, and the tumors frequently express cytokeratin 7. Type 2 tumor cells have pseudostratified nuclei and usually have voluminous eosinophilic cytoplasm. Recent studies have supported this subclassification of papillary renal cell carcinoma by demonstrating differing genotypes for type 1 and 2 tumors. To further study the subclassification of papillary renal carcinoma, we compared clinical features, nuclear grade, stage, tumor growth kinetics, and survival in a series of 50 type 1 and 16 type 2 papillary renal cell carcinomas. Comparison of patient age at presentation, sex, and primary tumor size shows no significant difference between the 2 tumor types. Type 1 tumors were of significantly lower Fuhrman grade (P =.0001) and higher Robson stage (P =.009) than type 2 tumors. There was no significant difference when tumors were staged according to the TNM classification. Assessment of tumor growth kinetics showed significantly different mean silver-staining nucleolar organizer region (AgNOR) scores and Ki-67 indices (AgNOR type 1, 3.83, type 2, 7.24, P =.0001; Ki-67 type 1, 3.17%, type 2, 6.01%, P =.0002). Multivariate analysis showed tumor type (P =.03), presence of metastases (P =.04), AgNOR score (P =.001), and Ki-67 index (P =.03) to be independently associated with survival. These results provide evidence of the clinical utility of dividing papillary renal cell carcinomas into 2 types according to histologic characteristics.

Biomarkers of renal cell carcinoma. Past and future considerations

Renal cancer includes several distinct entities with a range of biologic and clinical behaviors from relatively indolent to extremely aggressive tumors. Although conventional prognostic factors such as stage and grade are quite useful, other clinical, laboratory, and pathologic findings are now believed to have additional predictive values. This article reviews the literature on the potential utility of biomarkers in renal cell carcinoma. To date, only a few biomarkers, such as Ki-67, appeared to be potentially useful for monitoring renal cancer patients. New biomarkers including MN/CA9 and circulating cell detection require further and extensive studies to assess their potential clinical utility.

Value of immunohistochemical Ki-67 and p53 determinations as predictive factors of outcome in renal cell carcinoma

OBJECTIVES

Nuclear grade and tumor stage are important prognostic factors in renal cell carcinoma, but tumors of similar stage and grade can exhibit a wide variation in biologic behavior and clinical outcome. In this retrospective study, we evaluated the immunologic markers, Ki-67 (MIB1) and p53, in 73 cases of conventional (clear cell) renal cell carcinoma and compared these markers with the accepted prognostic features of grade, stage, and tumor size in predicting outcome.

METHODS

Specimens of 73 renal cell carcinomas of different nuclear grade (20 Furhman I/II, 32 Fuhrman III, and 21 Fuhrman IV) and different stage (10 pT1, 23 pT2, 36 pT3, and 4 pT4) were immunostained with monoclonal antibodies against Ki-67 and p53.

RESULTS

Univariate statistical analysis showed that tumor size (P <0. 001), nuclear grade (P <0.01), tumor stage (P <0.01), Ki-67 index (P <0.001), and p53 immunostaining (P <0.03) correlated significantly with a poor prognosis. A Ki-67 index of 20% was a powerful predictor of survival in all patients (P <0.00001), with strong predictive values. On multivariate analysis, the Ki-67 index and metastases were significant independent prognostic factors (P <0.02 and <0.01, respectively).

CONCLUSIONS

Ki-67 immunostaining appeared to be an additional prognostic indicator of biologic aggressiveness in renal cell carcinoma. Immunohistochemical assessment of tumor antigens could be used to identify patients at high risk of tumor progression in addition to conventional prognostic factors.

Prognostic indicators for renal cell carcinoma: a multivariate analysis of 643 patients using the revised 1997 TNM staging criteria

PURPOSE

We determine independent prognostic indicators for renal cell carcinoma using the revised 1997 TNM staging criteria.

MATERIALS AND METHODS

The records of 643 consecutive patients undergoing partial or radical nephrectomy at our institution between 1987 and 1998 were reviewed. Preoperative evaluation of functional status using the Eastern Cooperative Oncology Group (ECOG) criteria was performed in all cases. Renal cell carcinoma grade and stage were evaluated using the 1997 American Joint Committee on Cancer grading and TNM staging criteria, respectively. Patients were followed for a mean plus or minus standard deviation of 47+/-40 months (median 87). Kaplan-Meier survival curves were used to determine 5-year cancer specific survival for all patient groups. Univariate analysis using log rank sum tests was performed to evaluate the prognostic significance of overall TNM stage, tumor stage, disease grade and ECOG status. Multivariate analysis was performed to determine which factors had an independent impact on survival of patients with renal cell carcinoma.

RESULTS

The 5-year cancer specific survival rate was 91%, 74%, 67% and 32% for TNM stages I, II, III and IV lesions, respectively (p<0.001). Analysis demonstrated a survival rate of 83% for stage T1, 57% for stage T2, 42% for stage T3 and 28% for stage T4 disease (p<0.001), and 89% for grade 1, 65% for grade 2, and 46% for grades 3 and 4 (p<0.001). Multivariate analysis revealed that overall TNM stage and grade of disease were the most important prognostic indicators for renal cell carcinoma (p<0.001). ECOG classification was a less significant predictor (p = 0.031) and tumor stage was not shown to have any independent impact on patient survival (p = 0.138).

CONCLUSIONS

Better survival rates of patients with localized and advanced renal cell carcinoma can be demonstrated with recent advances in diagnosis and treatment. The revised 1997 TNM criteria manifest an appropriate adjustment in staging renal cell carcinoma based on these improvements, with overall stage correlating with cancer specific survival. In contrast, while effectively predicting survival, tumor stage did not demonstrate an independent impact on renal cell carcinoma prognosis under multivariate analysis. Instead, other factors, such as ECOG status and more importantly grade of disease, appeared to affect survival significantly as independent elements. Based on our recent experience with patients treated for renal cell carcinoma in the era of enhanced technology and improved survival, tumor grade and molecular markers may serve as useful adjuncts to TNM staging in guiding treatment and predicting survival outcomes.

Risk and prognosis in renal neoplasms. A pathologist's prospective

The incidence of renal carcinoma has increased in the United States over the last two decades. An increased rate of detection of incidental tumors and a variety of exogenous risk factors may be responsible for this increase. Pathologic stage and nuclear grade remain the most important and practical prognostic features, however, the specific tumor type has emerged as important as the cytogenetic validation of recent renal carcinoma classification. Proliferation markers, DNA ploidy, and morphometry have powerful predictive value but are handicapped by cost and complexity. The search continues for molecules of diagnostic and prognostic utility that may also impact invasive and metastatic capability for this group of neoplasms whose course is principally determined by the completeness of the original resection.

Prognostic factors of renal cell carcinoma: a multivariate analysis

BACKGROUND AND OBJECTIVES

To establish appropriate therapeutic modalities for renal cell carcinoma (RCC), informations on the factors affecting prognosis of patients are essential. For this purpose, multivariate analysis including a large set of variables is necessary.

METHODS

Prognostic significance of 14 clinical factors and 19 histologic factors including counting of silver-stained nucleolar organizer regions (AgNORs) were evaluated in 96 patients. Age of patients ranged from 41 to 85 (median 59) yr with a male to female ratio of 4:1. The tumors were staged based on the TNM classification as follows: 7 in stage I, 58 in stage II, 15 in stage III, and 11 in stage IV.

RESULTS

The overall and metastasis-free survival rates in all patients were 80.1% and 72.7%, respectively. Multivariate analysis using Cox's proportional hazards model performed on the factors proved to be significant at the univariate analysis. Univariate analysis revealed four clinical factors including presence of macroscopic hematuria, symptoms such as pain and palpable abdominal mass, anemia, and adjuvant therapy, and nine histologic factors, including AgNOR count, to be significant for survival. Multivariate analysis showed that anemia, pathological stage, and AgNOR count were independent factors for overall survival of patients. The AgNOR count, in particular, is the only predictive factor for metastasis-free survival.

CONCLUSIONS

Among various clinicopathological factors, anemia, pathological stage, and AgNOR count are significant prognosticators of RCC. The AgNOR count is also predictive factor for metastasis-free survival.

Appraisal of intratumoral microvessel density, MIB-1 score, DNA content, and p53 protein expression as prognostic indicators in patients with locally confined renal cell carcinoma

BACKGROUND

The prognostic values of intratumoral microvessel density (iMVD), tumor cell proliferation rate, DNA content (ploidy), and p53 protein expression are controversial or have not been well studied in patients with renal cell carcinoma (RCC) confined to the kidney.

METHODS

A uniform group of 52 clear cell (conventional) RCCs confined to the kidney (classified as T1N0M0 or T2N0M0) were analyzed for iMVD, MIB-1 score, DNA content, S-phase fraction, and p53 protein expression by immunohistochemical methods or flow cytometry. iMVD was evaluated in a single area (X200, 1.15 mm2) representative of the highest MVD (neovascular "hot spot") after independently highlighting endothelial cells with antibodies specific for factor VIII-related antigen (F8/86) and CD31 (JC/70A). The MIB-1 antibody (Ki-67 antigen) score was used as a marker for the tumor cell proliferation rate. DNA content and S-phase fraction were determined by flow cytometry using paraffin embedded tissue. p53 expression was assessed using the D07 antibody.

RESULTS

The median time of clinical follow-up was > 9 years. Eleven patients died of disease; the median time to death was 26 months. iMVD counts using antifactor VIII and anti-CD31 were tightly correlated (correlation coefficient = 0.89). S-phase fraction was higher in aneuploid tumors than in diploid tumors (mean, 12.4% vs. 4.3%; P = 0.01). Using univariate survival analyses, tumor size (stage classification pT1 vs. PT2; P = 0.01) and nuclear grade (P = 0.04) were associated with shortened survival. No statistically significant differences in survival were found for iMVD, MIB-1 score, DNA content, S-phase fraction, or p53 expression. Only two cases strongly expressed p53 protein; both tumors were of high nuclear grade. Using multivariate survival analyses, nuclear grade and tumor size were the only independent prognostic factors (best model P = 0.002).

CONCLUSIONS

In this study, nuclear grade and tumor size were found to be independent predictors of survival in locally confined clear cell (conventional) RCC, as has been shown previously for locally confined RCC in general. MIB-1 score, iMVD counts, DNA content, S-phase fraction, and p53 expression did not contribute additional prognostic information.

Microscopic vascular invasion is the most relevant prognosticator after radical nephrectomy for clinically nonmetastatic renal cell carcinoma

PURPOSE

Although many factors have been considered to predict the outcome after radical nephrectomy, renal cell carcinoma continues to behave unpredictably. In a retrospective study the correlation between microvascular tumor invasion and disease-free survival after surgery for renal cell carcinoma was analyzed.

MATERIALS AND METHODS

Between 1980 and 1993, 180 patients (mean age 60 years) were followed for a mean of 52 months after radical or partial nephrectomy for clinically localized renal cell carcinoma. The relevance of microscopic vascular invasion was compared to classical tumor staging, grade and tumor diameter.

RESULTS

Microscopic vascular invasion was found in 51 patients (28.3%), including 20 (39.2%) with progression (mean interval to progression 72 months). Of 129 patients with no pathological evidence of microscopic vascular invasion only 8 (6.2%) showed progression at a mean interval of more than 160 months. The difference in disease-free survival as a function of microvascular invasion was statistically highly significant (log rank p < 0.00001) and on multivariate analysis this parameter was by far the most relevant predictor of progression.

CONCLUSIONS

In patients who underwent radical nephrectomy for clinically nonmetastatic renal cell carcinoma with microvascular invasion but without lymph node involvement or macroscopic vascular invasion the chance of disease progression is estimated at 45% within 1 year. Microvascular invasion is the single most relevant prognosticator after presumed curative radical nephrectomy for renal cell carcinoma.