Development of renal cell carcinoma (RCC) diagnostics and impact on prognosis

Survival in Kidney and Bladder Cancers in Four Nordic Countries through a Half Century

Kidney and bladder cancers share etiology and relatively good recent survival, but long-term studies are rare. We analyzed survival for these cancers in Denmark, Finland, Norway (NO), and Sweden (SE) over a 50-year period (1971-2020). Relative 1- and 5-year survival data were obtained from the NORDCAN database, and we additionally calculated conditional 5/1-year survival. In 2016-2020, 5-year survivals for male kidney (79.0%) and bladder (81.6%) cancers were best in SE. For female kidney cancer, NO survival reached 80.0%, and for bladder cancer, SE survival reached 76.1%. The magnitude of 5-year survival improvements during the 50-year period in kidney cancer was over 40% units; for bladder cancer, the improvement was over 20% units. Survival in bladder cancer was worse for women than for men, particularly in year 1. In both cancers, deaths in the first year were approximately as many as in the subsequent 4 years. We could document an impressive development for kidney cancer with tripled male and doubled female 5-year survival in 50 years. Additionally, for bladder cancer, a steady improvement was recorded. The current challenges are to curb early mortality and target treatment to reduce long-term mortality.

Survival Improvement in Patients with Renal Cell Carcinoma and Disparities between Different Sexes, Races, and Socioeconomic Status: 1977–2016

Objective

Rare research of renal cell carcinoma (RCC) has been made in a comprehensive and full description based on a long period of time as yet. This study was aimed at investigating the incidence and relative survival rates (RSRs) of RCC in the past forty years and to disclose the impact of sex, race, and socioeconomic status (SES) on RCC.

Methods

The data as variables, including age, gender, race, and SES, were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. SES was divided into three levels: low poverty, medium poverty, and high poverty. The medium- and high-poverty groups were integrated into one group in all analyses. The RSRs were calculated using period analysis methodology. Summary statistics including incidence and RSRs were analyzed by Kaplan–Meier and Cox proportional hazards models with GraphPad Prism 8.0.1 software and Stata 12.0 software.

Results

A total of 77,513 patients diagnosed with RCC were enrolled in this study, showing an increased incidence and 10-year RSRs from 1977 to 2016. Patients older than 60 years had the highest incidence and the lowest RSRs. This research also showed significant disparities between different groups: incidence in males, blacks, and medium-high poverty groups was higher than that in females, whites, and low poverty groups, while RSRs were lower. For sex groups, the disparity of RSRs was obvious among patients who were 30–59 years old, but not among those younger than 29 years or older than 60 years. Based on SES, the survival gaps between different SES groups were getting wider over the past forty years.

Conclusion

This study showed how age, sex, race, and SES affected the incidence and RSRs of RCC, which may be beneficial for both better designed clinical trials and efficient prevention methods.

Survival in bladder and upper urinary tract cancers in Finland and Sweden through 50 years

Survival has improved in bladder cancer but few studies have considered extended periods or covered populations for which medical care is essentially free of charge. We analyzed survival in urothelial cancer (UC, of which vast majority are bladder cancers) in Finland and Sweden over a 50-year period (1967–2016) using data from the NORDCAN database. Finland and Sweden are neighboring countries with largely similar health care systems but higher economic resources and health care expenditure in Sweden. We present results on 1- and 5-year relative survival rates, and additionally provide a novel measure, the difference between 1- and 5-year relative survival, indicating how well survival was maintained between these two periods. Over the 50-year period the median diagnostic age has increased by several years and the incidence in the very old patients has increased vastly. Relative 1- year survival rates increased until early 1990s in both countries, and with minor gains later reaching about 90% in men and 85% in women. Although 5-year survival also developed favorably until early 1990s, subsequent gains were small. Over time, age specific differences in male 1-year survival narrowed but remained wide in 5-year survival. For women, age differences were larger than for men. The limitations of the study were lack of information on treatment and stage. In conclusion, challenges are to improve 5-year survival, to reduce the gender gap and to target specific care to the most common patient group, those of 70 years at diagnosis. The most effective methods to achieve survival gains are to target control of tobacco use, emphasis on early diagnosis with prompt action at hematuria, upfront curative treatment and awareness of high relapse requiring regular cystoscopy follow up.

Progress in survival in renal cell carcinoma through 50 years evaluated in Finland and Sweden

Global survival studies have shown favorable development in renal cell carcinoma (RCC) treatment but few studies have considered extended periods or covered populations for which medical care is essentially free of charge. We analyzed RCC survival in Finland and Sweden over a 50-year period (1967-2016) using data from the NORDCAN database provided by the local cancer registries. While the health care systems are largely similar in the two countries, the economic resources have been stronger in Sweden. In addition to the standard 1- and 5-year relative survival rates, we calculated the difference between these as a measure of how well survival was maintained between years 1 and 5. Relative 1- year survival rates increased almost linearly in both countries and reached 90% in Sweden and 80% in Finland. Although 5-year survival also developed favorably the difference between 1- and 5-year survival rates did not improve in Sweden suggesting that the gains in 5-year survival were entirely due to gains in 1-year survival. In Finland there was a gain in survival between years 1 and 5, but the gain in 1-years survival was the main contributor to the favorable 5-year survival. Age group specific analysis showed large survival differences, particularly among women. Towards the end of the follow-up period the differences narrowed but the disadvantage of the old patients remained in 5-year survival. The limitations of the study were lack of information on performed treatment and clinical stage in the NORDCAN database. In conclusion, the available data suggest that earlier diagnosis and surgical treatment of RCC have been the main driver of the favorable change in survival during the past 50 years. The main challenges are to reduce the age-specific survival gaps, particularly among women, and push survival gains past year 1.

Exploration of immune-related genes in high and low tumor mutation burden groups of chromophobe renal cell carcinoma

Renal cell carcinoma (RCC) is one of most common cancers with gradually increasing incidence and high mortality. Chromogenic RCC (chRCC) is the third most common histological subtype of RCC, accounting for approximately 5–7% of RCC. In our study, the transcriptome expression profile data (n=89) of chRCC, corresponding clinical data (n=113) and the somatic mutation data (n=66) were obtained from the TCGA database. We first analyzed the mutation data of chRCC patients and divided chRCC patients into high and low tumor mutation burden (TMB) groups based on the median TMB. We found that high TMB was significantly associated with worse prognosis and could promote tumor metastasis and development. Moreover, four different immune-related genes (BIRC5, PDGFRL, INHBE, IL20RB) were also identified. We found that BIRC5 was significantly overexpressed in the high TMB group and correlated with worse prognosis. The results of univariate and multivariate COX analyses demonstrated that BIRC5 (hazard ratio (HR) = 2.094) may serve as a prognostic indicator for patients with chRCC with high TMB. In addition, we identified the possible functional pathways of BIRC5 through gene set enrichment analysis (GSEA) enrichment. A positive correlation was obtained between BIRC5 and the abundance of CD4⁺ T cells. The results of our study revealed their correlation between the immune-related genes and clinicopathologic features as well as potential functional pathways as well as immune infiltrating cells, which may provide more data about the development of chRCC immunotherapy.

Imaging Characterization of Renal Masses

The detection of a renal mass is a relatively frequent occurrence in the daily practice of any Radiology Department. The diagnostic approaches depend on whether the lesion is cystic or solid. Cystic lesions can be managed using the Bosniak classification, while management of solid lesions depends on whether the lesion is well-defined or infiltrative. The approach to well-defined lesions focuses mainly on the differentiation between renal cancer and benign tumors such as angiomyolipoma (AML) and oncocytoma. Differential diagnosis of infiltrative lesions is wider, including primary and secondary malignancies and inflammatory disease, and knowledge of the patient history is essential. Radiologists may establish a possible differential diagnosis based on the imaging features of the renal masses and the clinical history. The aim of this review is to present the contribution of the different imaging techniques and image guided biopsies in the diagnostic management of cystic and solid renal lesions.

Multi-omics analysis reveals epithelial-mesenchymal transition-related gene FOXM1 as a novel prognostic biomarker in clear cell renal carcinoma

Identification of novel clinical biomarker in clear cell renal carcinoma (ccRCC) is warranted. Integrating transcriptome (n=1669), DNA methylation (n=577) and copy number data (n=832), we developed a method to identify driver biomarkers by analyzing the omics-level dynamics of Epithelial-Mesenchymal Transition (EMT)-related genes in ccRCC. We first identified 504 expression dynamic changed genes involved in ccRCC-associated key pathways such as EMT, cell cycle, EGFR and PI3K/AKT signaling. Further analysis identified 229 (90 gene promoters) aberrant expression quantitative trait methylation (eQTM) and 256 genes with expression quantitative trait copy number (eQTCN) alterations. Among them, FOXM1 was affected by both eQTM and eQTCN. FOXM1 copy number amplification (115/500, 23% of patients), occurred in an amplified peak in chromosome 12q13.3, was enriched in late-stage ccRCC samples and was associated with worse survival. FOXM1-overexpressed pT3 patients with distant metastasis showed ~25% shorter overall survival in both training (log-rank P=0.006) and validation (log-rank P=0.018) cohorts. The eQTM-gene hybrid signature (cg00044170 and FOXM1), superior to either gene expression or DNA methylation alone, showed great potential in diagnosing localized ccRCC in training (area under curve = 0.958) and validation datasets. FOXM1 could be a novel prognostic biomarker and shed light for early diagnosis at molecular level in ccRCC.

Decreased capillary density in renal cell carcinoma: Evidence from a case report with micro-computerized tomography

RATIONALE

Conventional computerized tomography (CT) examination can differentiate renal cortical tumor from urothelial carcinoma on the basis of the highly contrast-enhanced vessels in renal cortical tumors. However, the capillary distribution of renal cell carcinoma (RCC) has been under-investigated. Here, we present a micro-CT image of tumor tissue in a patient with RCC.

PATIENT CONCERNS

The patient was a 72-year-old woman with a past history of diabetes mellitus and hypertension. She did not have tumor-related symptoms.

DIAGNOSIS AND INTERVENTIONS

The tumor was diagnosed using abdominal CT during her yearly routine health check. After radical nephrectomy, the tumor was subjected to pathological examination and micro-CT imaging. Pathological analysis confirmed a clear cell renal carcinoma. The capillary distribution of the tumor was significantly lesser than that of the normal cortex on micro-CT image.

LESSONS

Microvessels of RCC can be detected by micro-CT. We also found that the distribution of microvessels was uneven and lower than that in the normal cortex in this case. For a more general diagnosis, more micro-CT images of RCC tumors are needed.

HOXA6 inhibits cell proliferation and induces apoptosis by suppressing the PI3K/Akt signaling pathway in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is the most common type of renal cell carcinoma and the incidence of this disease is increasing. The present study aimed to investigate the role of homeobox A6 (HOXA6) in the proliferation and apoptosis of ccRCC cells. Analysis of the GSE6344 dataset and immunohistochemistry revealed that the mRNA and protein expression levels of HOXA6 were suppressed in ccRCC tissues. To evaluate the roles of HOXA6 in cell proliferation and apoptosis, ccRCC cell lines (786‑O and 769‑P) were transfected with plasmids expressing HOXA6, empty vector, short hairpin (sh)HOXA6 and non‑targeting shRNA (NC). Cell Counting Kit‑8, colony formation and 5‑ethynyl‑2'‑deoxyuridine staining assays were performed to analyze cell proliferation. In addition, Caspase‑Glo and terminal deoxynucleotidyl transferase dUTP nick end labeling assays were performed to detect apoptosis. Furthermore, the cell cycle and apoptotic rates of 786‑O and 769‑P cells were analyzed by flow cytometry. The results demonstrated that, compared with the empty vector group, the proliferation of 786‑O and 769‑P cells decreased following HOXA6 overexpression; however, compared with the NC group, cell proliferation increased in the shHOXA6 group. The rate of apoptosis of HOXA6‑overexpressing cells was increased compared with the empty vector group, while the rate of apoptosis in the shHOXA6 group was reduced compared with the NC group. In addition, flow cytometry demonstrated that upregulated HOXA6 expression levels could inhibit the cell cycle at the G0/G1 phase. Western blotting revealed that the expression levels of phosphoinositide 3‑kinase (PI3K), phosphorylated (p)‑protein kinase B (Akt), mitogen‑activated protein kinase kinase, p‑extracellular signal‑regulated kinase (ERK) and B‑cell lymphoma 2 (Bcl‑2) were suppressed in cells overexpressing HOXA6; however, the protein expression levels of phosphatase and tensin homolog, Bcl‑2‑associated X protein, cleaved caspase‑3 and cleaved‑poly (ADP‑ribose) polymerase were increased compared with the empty vector group. Opposing results were reported for the shHOXA6 group compared with the NC group. In summary, the results demonstrated that HOXA6 suppresses cell proliferation and promotes apoptosis, which may occur via inhibition of the PI3K/Akt/ERK cascade. These findings indicate the role of HOXA6 in ccRCC; however, the underlying mechanism requires further investigation.

Dynamic changes of different phenotypic and genetic circulating tumor cells as a biomarker for evaluating the prognosis of RCC

BACKGROUND

Circulating tumor cells (CTCs) and relevant autophagy Beclin-1 genes expression are critical biomarkers for tumorigenesis and tumor progress. Here we investigated the relationship of dynamic changes of CTCs and Beclin-1 expression of CTCs with renal cell carcinoma (RCC) prognosis.

MATERIALS AND METHODS

A total of 69 patients with RCC were enrolled and divided into two groups based on the postoperative status of distant metastasis, including metastasis-free group (n = 58) and metastatic group (n = 11). Demographic characteristics of each patient were recorded in detail. All 69 enrolled patients had received multiple CTC tests and peripheral blood samples were obtained at three different time points (1 day before operation, 6 months and 12 months after operation). Peripheral blood samples were drawn before each time point and CTCs were separated by using Can Patrol CTC enrichment technique. CTCs were divided into epithelial, mesenchymal and mixed phenotype based on different surface biomarkers. RNA in situ hybridization assay was used to detect the expression of Beclin1 gene.

RESULTS

The percentages of epithelial, mesenchymal and mixed CTCs were 11.64%, 28.04% and 60.32%, respectively. There were no significant differences of initial CTCs counts between metastasis-free group (8.43 ± 5.15) and metastatic group (7.71 ± 3.82) (P > 0.05). As for metastatic group, the number of mixed CTCs at 12 months postoperatively was significantly higher than that of mixed CTCs preoperatively and 6 months postoperatively (P < 0.05). In the metastatic group, the number of Beclin1 positive CTCs was significantly higher than that of Beclin1 negative CTCs preoperatively (P < 0.05), moreover, there were several significantly changes of Beclin1 positive CTCs with different types and at different time points.

CONCLUSION

The recurrence or metastasis of RCC was uncorrelated with initial CTCs counts, but probably related with the variation trend of CTCs, especially mesenchymal CTCs and Beclin1 positive CTCs.

National recommendations document on the follow-up of patients with renal cell carcinoma

OBJECTIVES

This document was developed to establish directives for the follow-up of patients with renal cell carcinoma (RCC) based on the best available scientific evidence and on expert opinions, which can help urologists in the decision-making process and standardise the criteria at the national level.

MATERIAL AND METHODS

The methodology is based on the RAND/UCLA method. A panel of 9 experts on RCC participated in designing a thematic index, identifying and reading the available evidence, formulating recommendations and drafting the content. A validating group of 25 experts, who did not participate in the previous phases, assessed the recommendations through anonymous voting in a face-to-face consensus meeting. The recommendations that were agreed upon by 75% or more of the participants in this vote were accepted as consensus. The recommendations that did not achieve this consensus were rejected.

RESULTS

A total of 25 recommendations were accepted as consensus. These recommendations cover the laboratory tests, clinical assessment tests and imaging tests that should be performed for patients with RCC. The presented recommendations have been adapted according to relapse risk. The current document also outlines the frequency and duration of follow-up for each patient profile.

CONCLUSIONS

The current document enables standardisation of the follow-up criteria for patients with RCC treated in the Spanish healthcare setting, according to the patients' relapse risk.

Novel Angiogenesis Markers as Long-Term Prognostic Factors in Patients With Renal Cell Cancer

OBJECTIVE

To evaluate Ang-2 expression alone and in combination with expression of cell proliferation and cell survival markers (MIB-1 and Bcl-2) and angiogenesis markers (VEGFR3 and CD31), and the associations of these markers with renal cell cancer (RCC) in long-term survival.

PATIENTS AND METHODS

Our study included 224 patients with RCC who were treated before the availability of antiangiogenic agents between 1985 and 1995, at the Pirkanmaa Hospital District in Finland. All tumor samples were reclassified and reevaluated by an experienced uropathologist, and parallel tissue microarrays (TMA) were performed for immunohistochemical analysis. Kaplan-Meier's survival estimation method and Cox proportional hazards models were used for survival analysis.

RESULTS

The percentage of Ang-2 expression in the tumor area varied from 0.07 to 25.65. Ang-2 expression was significantly associated with the tumor grade and stage, as well as the MIB-1, Bcl-2, and VEGFR3 expression (P = .042, P = .019, P = .039, P = .013, and P = .005, respectively). The highest Ang-2 expression predicted better survival, P < .05. High Bcl-2 and low MIB-1 expression combined with Ang-2 expression was associated with better survival. Multivariate analysis showed poorer survival in patients with low Ang-2 or high MIB-1 expressions: HR 1.89, 95% CI 1.16 to 3.08, P = .010 and HR 2.20, 95% CI 1.36 to 3.54, P = .001, respectively.

CONCLUSIONS

Very high Ang-2 expression was associated with better survival in patients with RCC. Ang-2 expression correlated with tumor stage and grade, but it was still an independent prognostic factor in a multivariate analysis.

MicroRNA-194 is a Marker for Good Prognosis in Clear Cell Renal Cell Carcinoma

Clear cell renal cell carcinoma (ccRCC) is the most prevalent adult kidney cancer. Prognostic markers are needed to guide patient management toward aggressive versus more conservative approaches, especially for small tumors ≤4 cm. miR‐194 was reported to be downregulated in several cancers and is involved in epithelial to mesenchymal transition. We evaluated miR‐194 as a prognostic marker in ccRCC. In a cohort of 234 patients with primary ccRCC, we correlated miR‐194 expression level with multiple clinicopathological features including disease‐free and overall survival, tumor size, clinical stage, and histological grade. Our results shows a stepwise decrease in miR‐194 expression from normal kidney to primary ccRCC (P = 0.0032) and a subsequent decrease from primary to metastatic lesions. Additionally, patients with higher miR‐194 expression has significantly longer disease‐free survival (P = 0.041) and overall survival (P = 0.031) compared to those with lower expression. In multivariate analysis, miR‐194‐positive tumors retain significance in disease‐free survival and overall survival, suggesting miR‐194 is an independent marker for good prognosis in ccRCC. Moreover, miR‐194 is a marker for good prognosis for patients with small renal masses (P = 0.014). These findings were validated on an independent data set from The Cancer Genome Atlas. We also compared miR‐194 expression between RCC subtypes. ccRCC had the highest levels, whereas chromophobe RCC and oncocytoma had comparable lower levels. Target prediction coupled with pathway analysis show that miR‐194 is predicted to target key molecules and pathways involved in RCC progression. miR‐194 represents a prognostic biomarker in ccRCC.