Lifestyle Factors, Exposures, Genetic Susceptibility, and Renal Cell Cancer Risk: A Review

Kidney Cancer Incidence among Non-Hispanic American Indian and Alaska Native Populations in the United States, 1999 to 2020

BACKGROUND

Non-Hispanic American Indian and Alaska Native (NH-AI/AN) people exhibit a disproportionate incidence of kidney cancer. Nationally aggregated data do not allow for a comprehensive description of regional disparities in kidney cancer incidence among NH-AI/AN communities. This study examined kidney cancer incidence rates and trends among NH-AI/AN compared with non-Hispanic White (NHW) populations by geographic region.

METHODS

Using the United States Cancer Statistics American Indian and Alaska Native (AI/AN) Incidence Analytic Database, age-adjusted incidence rates (per 100,000) of kidney cancers for NH-AI/AN and NHW people for the years 2011 to 2020 combined using surveillance, epidemiology, and end Results (SEER)∗stat software. Analyses were restricted to non-Hispanic individuals living in purchased/referred care delivery area (PRCDA) counties. Average annual percent changes (AAPCs) and trends (1999-2019) were estimated using Joinpoint regression analyses.

RESULTS

Rates of kidney cancer incidence were higher among NH-AI/AN compared with NHW persons in the United States overall and in five of six regions. Kidney cancer incidence rates also varied by region, sex, age, and stage of diagnosis. Between 1999 and 2019, trends in kidney cancer rates significantly increased among NH-AI/AN males (AAPC = 2.7%) and females (AAPC = 2.4%). The largest increases were observed for NH-AI/AN males and females aged less than 50 years and those diagnosed with localized-stage disease.

CONCLUSIONS

Study findings highlight growing disparities in kidney cancer incidence rates between NH-AI/AN and NHW populations.

IMPACT

Differences in geographic region, sex, and stage highlight the opportunities to decrease the prevalence of kidney cancer risk factors and improve access to preventive care.

Trends and projections of the global burden of thyroid cancer from 1990 to 2030

Background

We aimed to explore the burden of thyroid cancer worldwide from 1990 to 2019 and to project its future trends from 2020 to 2030.

Methods

Based on annual data on thyroid cancer cases from 1990 to 2019 available in the Global Burden of Disease (GBD) database, we calculated the age-standardised incidence, death, and disability-adjusted life year (DALY) rates for thyroid cancer. We used the estimated annual percentage change (EPAC) to quantify the temporal trends in these age-standardised rates from 1990 to 2019 and applied generalised additive models to project the disease burden from 2020 to 2030.

Results

The global age-standardised incidence rate (ASIR) of thyroid cancer increased from 1990 to 2019, with a higher overall disease burden in women than in men at both study time points. The male-to-female ratios for the ASIR increased from 0.41 in 1990 to 0.51 in 2019, while the ratio for the age-standardised death rate (ASDR) increased from 0.60 to 0.82. The models predicted the United Arab Emirates would have the fastest rising trend in both the ASIR (estimated annual percentage changes (EAPC) = 4.19) and age-standardised DALY rate (EAPC = 4.36) in 2020-30, while Saint Kitts and Nevis will have the fastest rising trend in the ASDR (EAPC = 2.29). Meanwhile, the growth trends for the ASDR and age-standardised DALY rate are projected to increase across countries in this period. A correlation analysis of the global burden of thyroid cancer between 1990-2019 and 2020-30 showed a significant positive correlation between the increase in the ASIR and socio-demographic index (SDI) in low-SDI and low-middle-SDI countries.

Conclusions

The global burden of thyroid cancer is increasing, especially in the female population and in low-middle-SDI regions, underscoring a need to target them for effective prevention, diagnosis, and treatment.

Citrus fruit intake and incidence of renal cell carcinoma: A meta-analysis of observational studies

Observational studies on the association between citrus fruit intake and risk of renal cell carcinoma (RCC) have reported inconsistent results. We quantitatively assessed this association by conducting a meta-analysis. PubMed and Embase databases search was conducted including relevant studies published up to January, 2020. We included epidemiological studies that reported relative risks (RRs) or odds ratios (ORs) with 95% confidence intervals (CIs) for the association between citrus fruit intake and RCC risk. A total of eight epidemiological studies consisting of five cohort and three case-control studies were included. The overall analysis showed a significantly reduced risk of RCC for high intake of citrus fruit (OR = 0.84, 95% CI 0.73-0.95). No heterogeneity was detected among the included studies (p = 0.497 for heterogeneity; I2 = 0). There was no significant publication bias by Begg's test (p = 0.266) or Egger's test (P = 0.578). A statistically significant association between citrus fruit intake and RCC was observed in case-control studies (OR = 0.84, 95% CI 0.71-0.98), while no association was observed in cohort studies (OR = 0.84, 95% CI 0.64-1.05). In addition, the dose-response analysis indicated that the RCC risk reduced by 13% (95%CI 1.0%-27%, p = 0.04 for heterogeneity) for each 100 grams per day increment of citrus fruit intake. In summary, our findings suggest an inverse association between citrus fruit intake and RCC incidence.

Green tea and coffee consumption and risk of kidney cancer in Japanese adults

The study aimed to evaluate the association between green tea and coffee consumption and the risk of kidney cancer using data from a large prospective cohort study in Japan (the Japan Public Health Center-based Prospective Study: JPHC Study). A total of 102,463 participants aged 40-69 were followed during 1,916,421 person-years (mean follow-up period, 19 years). A total of 286 cases of kidney cancer (199 in men, 87 in women) were identified. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs) while adjusting for potential confounders. No statistically significant association between green tea intake and kidney cancer risk was found in the total population. Among women who consumed more than five cups of green tea per day, a statistically significant decreased risk was shown with a HR of 0.45 (95% CI: 0.23-0.89), compared to women who rarely consumed green tea. For coffee consumption, the association of kidney cancer risk was not statistically significant. This large prospective cohort study indicated green tea intake may be inversely associated with kidney cancer risk in Japanese adults, particularly in Japanese women.

Cancer mortality in a population-based cohort of American Indians - The strong heart study

BACKGROUND

Cancer mortality among American Indian (AI) people varies widely, but factors associated with cancer mortality are infrequently assessed.

METHODS

Cancer deaths were identified from death certificate data for 3516 participants of the Strong Heart Study, a population-based cohort study of AI adults ages 45-74 years in Arizona, Oklahoma, and North and South Dakota. Cancer mortality was calculated by age, sex and region. Cox proportional hazards model was used to assess independent associations between baseline factors in 1989 and cancer death by 2010.

RESULTS

After a median follow-up of 15.3 years, the cancer death rate per 1000 person-years was 6.33 (95 % CI 5.67-7.04). Cancer mortality was highest among men in North/South Dakota (8.18; 95 % CI 6.46-10.23) and lowest among women in Arizona (4.57; 95 % CI 2.87-6.92). Factors independently associated with increased cancer mortality included age, current or former smoking, waist circumference, albuminuria, urinary cadmium, and prior cancer history. Factors associated with decreased cancer mortality included Oklahoma compared to Dakota residence, higher body mass index and total cholesterol. Sex was not associated with cancer mortality. Lung cancer was the leading cause of cancer mortality overall (1.56/1000 person-years), but no lung cancer deaths occurred among Arizona participants. Mortality from unspecified cancer was relatively high (0.48/100 person-years; 95 % CI 0.32-0.71).

CONCLUSIONS

Regional variation in AI cancer mortality persisted despite adjustment for individual risk factors. Mortality from unspecified cancer was high. Better understanding of regional differences in cancer mortality, and better classification of cancer deaths, will help healthcare programs address cancer in AI communities.

Alcohol consumption, tobacco smoking, and subsequent risk of renal cell carcinoma: The JPHC study

The effects of alcohol consumption and tobacco smoking on renal cell carcinoma (RCC) incidence have not been well‐investigated in Asian populations. Here, we evaluated these effects in a large Japanese prospective cohort. We collected data on eligible participants in the Japan Public Health Center‐based Prospective Study, and undertook multivariable‐adjusted Cox proportional hazards regression to estimate hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) of RCC incidence. We identified 340 cases (230 men and 110 women) among the 105 663 eligible participants (50 262 men and 55 741 women), who were followed for an average of 19.1 years, with a cumulative total of 2 020 364 person‐years. A slightly inverse but nonsignificant association was observed between alcohol drinking and RCC incidence. In contrast, the risk of RCC was increased in those with heavy smoking (≥40 pack‐years) when men and women were combined (HR 1.50; 95% CI, 1.01‐2.25). We identified no significant association between alcohol consumption and RCC incidence. In contrast, heavy smoking (≥40 pack‐years) was associated with a significant increase in incidence.

Using a large prospective cohort in Japan, we evaluated the effects of alcohol consumption and tobacco smoking on renal cell carcinoma (RCC). Our analyses showed no significant association between alcohol consumption and RCC incidence. In contrast, heavy smoking (≥40 pack‐years) was associated with a significant increase in incidence.

Smoking-adjusted risk of kidney cancer by occupation: a population-based cohort study of Nordic men

Background: Evidence suggests that among some occupational groups, there is an elevated risk of kidney cancer. This might, however, derive from a difference in smoking habits across occupational groups. The objective of this study was to determine smoking-adjusted occupational variation in the incidence of kidney cancer in Nordic males.Material and Methods: The source population for this study consisted of 7.4 million men from Denmark, Iceland, Finland, Norway, and Sweden. Data on occupation were obtained from national censuses conducted in the years 1960-1990. Data on cancer cases came from national cancer registries. A proxy for the occupation-specific smoking prevalence among all Nordic men was calculated based on the occupation-specific smoking prevalence and lung cancer incidence data for Finnish men. Smoking-adjusted standardized incidence ratio (SIRadj) with 95% confidence intervals (95%CI) were calculated for each occupational group.Results: The highest SIRadj estimates were observed in dentists (1.32, 95%CI 1.06-1.62), journalists (1.20, 95%CI 1.00-1.42), physicians (1.19, 95%CI 1.03-1.36), public safety workers (1.18, 95%CI 1.10-1.26), administrators (1.17, 95%CI 1.13-1.22), military personnel (1.16, 95%CI 1.05-1.28), and religious workers (1.17, 95%CI 1.09-1.26). The lowest SIRadj was observed among forestry workers (0.82, 95%CI 0.76-0.88).Conclusions: Tobacco smoking plays an important role in the occupational variation in the risk of kidney cancer. The smoking-adjusted incidence of kidney cancer was increased in dentists, physicians, journalists, administrators, and public safety workers.

RGS5 plays a significant role in renal cell carcinoma

Recent advances in biotechnology led to generation of large complex biological and clinical datasets that can be used to infer the underlying mechanism of many diseases and arrive at personalized treatments. One of these datasets are the whole genome profiles, including a good collection of publicly available human gene expression datasets. In this project, we analysed gene expression profiles of patients with renal cell carcinoma (RCC). We found that the regulator of G-protein signalling 5 (RGS5) might play a crucial role in initiation and progression of RCC, and it might be prognostic. We observed that a high expression level of RGS5 is associated with better survival months. Importantly, when the grade of tumour increases, the RGS5 expression level significantly decreases. Although there is no difference between expression level of RGS5 in male and female patients with primary tumours in the right kidney, among patients with primary tumours in the left kidney, females have a significantly higher RGS5 expression than male patients. Interestingly, we also observed a significant association between the high expression level of RGS5 and low serum calcium level and elevated white blood cells level.

Hypertensive nephropathy is associated with an increased risk of myeloma, skin, and renal cancer

Previous studies suggest an increased cancer risk in hypertension. Patients with hypertensive nephropathy have not been studied. A national registry study was performed to assess the presence and size of this association. Clinical data and cancer diagnoses for all patients with biopsy-proven hypertensive nephropathy between 1985 and 2015 in Denmark were extracted from four national registries and compared with age- and sex-adjusted national cancer rates. The risk of cancer was twice the background population. It was raised for renal cancer (odds ratio 10.4), myeloma (13.2), skin cancer (7.9), and other/unspecified (1.8). No increase in incidence was seen until 1 year before renal biopsy and then rose rapidly. It was again normal 5 years after biopsy. Hypertensive nephropathy is associated with an increased risk of myeloma, skin, renal, and other cancers. Screening of patients with hypertensive nephropathy, in the presence of reduced renal function or significant proteinuria, may be indicated.

Obesity and Cancer: Existing and New Hypotheses for a Causal Connection

Existing explanations of obesity-associated cancer emphasise direct mutagenic effects of dietary components or hormonal imbalance. Some of these hypotheses are reviewed briefly, but recent evidence suggests a major role for chronic inflammation in cancer risk, possibly involving dietary content. These ideas include the inflammation-induced activation of the kynurenine pathway and its role in feeding and metabolism by activation of the aryl hydrocarbon receptor (AHR) and by modulating synaptic transmission in the brain. Evidence for a role of the kynurenine pathway in carcinogenesis then provides a potentially major link between obesity and cancer. A second new hypothesis is based on evidence that serine proteases can deplete cells of the tumour suppressors Deleted in Colorectal Cancer (DCC) and neogenin. These enzymes include mammalian chymotryptic proteases released by pro-inflammatory neutrophils and macrophages. Blood levels of chymotrypsin itself increase in parallel with food intake. The mechanistically similar bacterial enzyme subtilisin is widespread in the environment, animal probiotics, meat processing and cleaning products. Simple public health schemes in these areas, with selective serine protease inhibitors and AHR antagonists and could prevent a range of intestinal and other cancers.

Blood pressure and kidney cancer risk: meta-analysis of prospective studies

BACKGROUND

Globally, kidney cancer is the twelfth most common cancer, accounting for 337 860 cases recorded in 2012. By 2020, this number has been estimated to reach 412 929 or increase by 22%. Over the past few decades, a number of prospective studies have investigated the association between blood pressure (BP) and risk of kidney cancer, using either recorded BP levels or reported hypertension as the principal exposure variable. However, the relation of BP to kidney cancer remains incompletely understood, and the data on sex-specific differences in risk estimates have been inconsistent.

METHOD

PubMed and Web of Science databases were searched for studies assessing the association between BP and kidney cancer through July 2016. The summary relative risk with 95% confidence intervals was calculated using a random-effects model.

RESULT

A total of 18 prospective studies with 8097 kidney cancer cases from 3 628 479 participants were included in our meta-analysis. History of hypertension was associated with 67% increased risk of kidney cancer. Significant heterogeneity and evidence of publication bias were observed. However, the results remain unchanged after introducing the trim and fill method to correct the publication bias. Accordingly, each 10-mmHg increase in SBP and DBP was associated with 10 and 22% increased risk of kidney cancer.

CONCLUSION

Collectively, the present meta-analysis of 18 prospective studies provides further support for a positive association between hypertension and kidney cancer risk.

Association of body mass index with mortality and postoperative survival in renal cell cancer patients, a meta-analysis

Obesity is one of the major risk factors of cancer. However, how body mass index (BMI) influences the prognosis of renal cell cancer (RCC) patient is unclear. In this work, we have performed a meta-analysis to elucidate the role of abnormal weight in RCC mortality and postoperative survival. Articles related to BMI and RCC mortality as well as postoperative survival has been identified by searching PUBMED and ENBASE. Totally, 19 articles have been selected for this meta-analysis, 5 articles for RCC mortality and 14 for postoperative survival. Compared to normal weight, the estimated relative risks of RCC mortality are 0.71 (95% CI: 0.34–1.49), 1.19 (95% CI: 1.05–1.35) and 1.71 (95% CI: 1.27–2.00) respectively for the underweight, overweight and obesity patients. The risk of RCC mortality increase 5% for each 1 kg/m² increment of BMI. However, the estimated hazard ratios of cancer specific postoperative survival are 2.62 (95% CI: 1.67–4.11), 0.72 (95% CI: 0.63–0.83) and 0.66 (95% CI: 0.49–0.89) respectively for underweight, overweight and obesity RCC patients. The risk of hazard ratio decrease 5% for each 1 kg/m² increment of BMI. In addition, the hazard ratios of postoperative overall survival show a similar tendency. These results indicate an opposite association of BMI with mortality and postoperative survival in renal cell cancer patients.

MicroRNA-186 Suppresses Cell Proliferation and Metastasis Through Targeting Sentrin-Specific Protease 1 in Renal Cell Carcinoma

Recent evidence suggests that dysregulation of microRNAs is associated with the development of multiple malignancies. miR-186 has been reported as a critical cancer regulator in several types of cancers. However, its functional significance and molecular mechanism underlying renal cell carcinoma (RCC) remain unknown. In this study, our results showed that miR-186 expression was dramatically downregulated in RCC tissues and cell lines compared to that in adjacent normal tissues and cell lines. Overexpression of miR-186 significantly inhibited cell growth, colony formation, and cell invasion; caused cell cycle arrest at the G₀/G₁ phase; and induced cell apoptosis as detected by MTT, colony formation, Transwell assay, and flow cytometry assays in RCC cells. In addition, inhibition of miR-186 expression promoted RCC cell proliferation, invasion, and cell cycle progression and reduced apoptosis. Bioinformatics analysis and luciferase reporter assay confirmed that the 3′-UTR of sentrin-specific protease 1 (SENP1) was a direct target of miR-186. A remarkably reverse correlation was observed between miR-186 and SENP1 mRNA in RCC tissues. Furthermore, immunohistochemical staining revealed that SENP1 was positively expressed in RCC specimens. Restoration of SENP1 expression could partially abrogate the inhibitory effect of miR-186 overexpression on RCC cell proliferation through activating NF-κB signaling and its downstream proteins. These data demonstrated that miR-186 acted as a novel tumor suppressor and potential therapeutic biomarker in the progression of RCC by directly targeting SENP1.

American Confederation of Urology (CAU) experience in minimally invasive partial nephrectomy

PURPOSE

To describe the perioperative and oncology outcomes in a series of laparoscopic or robotic partial nephrectomies (PN) for renal tumors treated in diverse institutions of Hispanic America from the beginning of their minimally invasive (MI) PN experience through December 2014.

METHODS

Seventeen institutions participated in the CAU generated a MI PN database. We estimated proportions, medians, 95 % confidence intervals, Kaplan-Meier curves, multivariate logistic and Cox regression analyses. Clavien-Dindo classification was used.

RESULTS

We evaluated 1501 laparoscopic (98 %) or robotic (2 %) PNs. Median age: 58 years. Median surgical time, warm ischemia and intraoperative bleeding were 150, 20 min and 200 cc. 81 % of the lesions were malignant, with clear cell histology being 65 % of the total. Median maximum tumor diameter is 2.7 cm, positive margin is 8.2 %, and median hospitalization is 3 days. One or more postoperative complication was recorded in 19.8 % of the patients: Clavien 1: 5.6 %; Clavien 2: 8.4 %; Clavien 3A: 1.5 %; Clavien 3B: 3.2 %; Clavien 4A: 1 %; Clavien 4B: 0.1 %; Clavien 5: 0 %. Bleeding was the main cause of a reoperation (5.5 %), conversion to radical nephrectomy (3 %) or open partial nephrectomy (6 %). Transfusion rate is 10 %. In multivariate analysis, RENAL nephrometry score was the only variable associated with complications (OR 1.1; 95 % CI 1.02-1.2; p = 0.02). Nineteen patients presented disease progression or died of disease in a median follow-up of 1.37 years. The 5-year progression or kidney cancer mortality-free rate was 94 % (95 % CI 90, 97). Positive margins (HR 4.98; 95 % CI 1.3-19; p = 0.02) and females (HR 5.6; 95 % CI 1.7-19; p = 0.005) were associated with disease progression or kidney cancer mortality after adjusting for maximum tumor diameter.

CONCLUSION

Laparoscopic PN in these centers of Hispanic America seem to have acceptable perioperative complications and short-term oncologic outcomes.

P53 and MDM2 Over-expression and Five-year Survival of Kidney Cancer Patients Undergoing Radical Nephrectomy--Iranian Experience

BACKGROUND

Relatively little is known with certainty about the status and role of p53 or MDM2 in predicting prognosis and survival of renal cell carcinoma. The present study aimed to determine the value of P53 and MDM2 over-expression, alone and simultaneously, to predict five-year survival of patients with kidney cancer in Iran.

MATERIALS AND METHODS

Patients with kidney cancer referred to Hasheminejad Kidney Center between 2007 and 2009, underwent radical nephrectomy and had pathology reports of clear cell, papillary or chromophobe renal cell carcinoma were included in our cohort study. Other histological types of renal cell carcinoma were not included. The patients with missed, incomplete or poor quality paraffin blocks were also excluded. Overall ninety one patients met the inclusion and exclusion criteria. To assess the histopathological features of the tumor, immunohistochemical (IHC) staining of formalin fixed, paraffin-embedded tumor samples were performed. The five-year survival was determined by the patients' medical files and telephone following-up.

RESULTS

In total, 1.1% of all samples were revealed to be positive for P53. Also, 20.8% of all samples were revealed to be positive for MDM2.The patients were all followed for 5 years. In this regard, 5-year mortality was 30.5% and thus 5-year survival was 85.3%. According to the Cox proportional hazard analysis, positive P53 marker was only predictor for patients' 5-year survival that the presence of positive p53 increased the risk for long-term mortality up to 2.8 times (HR=2.798, 95%CI: 1.176-6.660, P=0.020). However, the presence of MDM2 could not predict long-term mortality. In this regard, analysis by the ROC curve showed a limited role for predicting long-term survival by confirming P53 positivity (AUC=0.610, 95%CI: 0.471-.750, P=0.106). The best cutoff point for P53 to predict mortality was 0.5 yielding a low sensitivity (32.0%) but a high specificity (97.9%). In similar analysis, measurement of MDM2 positivity could not predict mortality (AUC=0.449, 95%CI: 0.316-.583, P=0.455).

CONCLUSIONS

The simultaneous presence of both P53 and MDM2 markers in our population is a rare phenomenon and the presence of these markers may not predict long-term survival in patients who undergoing radical nephrectomy.

GSTT1 Null Genotype Significantly Increases the Susceptibility to Urinary System Cancer: Evidences from 63,876 Subjects

GSTT1 gene plays an important role in detoxification and clearance of reactive oxygen species(ROS). A null variant in this gene has been demonstrated to confer cancer susceptibility. Although many studies have demonstrated the association between GSTT1 null polymorphism and urinary system cancer susceptibility, several publications reported opposite conclusions. For better understanding the effects of this polymorphism on the risk of urinary system cancer, a updated meta-analysis was performed with a total of 26,666 cases and 37,210 controls extracted from 117 studies, by following the latest meta-analysis guidelines (PRISMA). The results suggested that the GSTT1 null genotype was significantly associated with an increased risk of urinary system cancer (OR=1.13, 95%CI=1.05-1.22). Furthermore, stratified analyses by the type of cancer, ethnicity, source of control and quality score presented a significantly increased risk associated with GSTT1 null genotype in bladder and prostate cancer subgroup, Caucasians and Indians subgroup, population-based(PB) subgroup, medium quality and low quality subgroup. Overall, our meta-analysis suggested that GSTT1 null genotype is a potential cancer susceptibility variant. Well-designed and large-cohort studies are needed to confirm the association between GSTT1 null genotype and urinary system cancer risk.

GSTM1 and GSTT1 polymorphisms contribute to renal cell carcinoma risk: evidence from an updated meta-analysis

Emerging evidences suggest that GSTM1 and GSTT1 are involved in the detoxification of carcinogens, and polymorphisms in this gene that result in a loss of enzyme activity may increase the risk of renal cell carcinoma (RCC). Thus, to evaluate the association of GSTM1 and GSTT1 polymorphisms and RCC, we performed an updated meta-analysis of 10 case-control studies by RevMan 5.2, and the publication bias was tested using STATA 11.0. The meta-analysis showed that the single locus GSTM1 and GSTT1 polymorphisms were not significantly associated with a risk of RCC in a recessive model. However, that wild-type genotype versus the dual null genotype of GSTM1-GSTT1 showed a positive association with RCC risk (OR = 0.70; 95% CI = 0.51-0.98; P = 0.04). In another analysis of subjects exposed to pesticides, we found that the GSTM1 wild-type genotype was associated with increased RCC risk in Europeans (OR = 2.72; 95% CI = 1.54-4.82; P = 0.0006). We also identified an association between the GSTT1 wild-type and lower RCC TNM staging (I + II versus III + IV: OR = 1.88; 95% CI = 1.09-3.26; P = 0.02). This meta-analysis suggests that there may be a relationship between the GSTM1 and GSTT1 wild-type genotype and RCC.

Vitamin C intake and risk of renal cell carcinoma: a meta-analysis

Studies have showed that vitamin C intake is linked to renal cell carcinoma risk, however, the results were inconsistent. Hence, the present meta-analysis was to examine the association between vitamin C intake and RCC risk. We searched the published studies that reported the relationship between vitamin C intake and RCC risk using PubMed and Embase up to January 2015. Based on a fixed effects model, RR and the corresponding 95% CI were used to assess the pooled risk. 3 prospective cohort studies and 7 case-control studies were included. The overall RR (95% CI) of RCC for the highest vs. the lowest levels of vitamin C intake was 0.78(0.69,0.87). Little evidence of heterogeneity was found. In the subgroup analyses, we found an inverse association between vitamin C intake and RCC risk in the case-control studies but not in the prospective cohort studies. Additionally, this association between vitamin C intake and RCC risk was not differed by population distribution. Our study provides evidence that vitamin C intake is associated with a reduced RCC risk. However, our conclusion was just based on ten including studies, so more high-quality of case-control studies or cohort studies which report this topic are needed.

Geographic Variation of Chronic Kidney Disease Prevalence: Correlation with the Incidence of Renal Cell Carcinoma or Urothelial Carcinoma?

Background. The aim of this study is to evaluate whether geographic variations in the prevalence of late-stage chronic kidney disease (CKD) exist and are associated with incidence rates of renal cell carcinoma (RCC), upper tract urothelial carcinoma (UTUC), or lower tract urothelial carcinoma (LTUC). Methods. Prevalence rates of late-stage CKD for 366 townships (n > 30) in Taiwan were calculated for 1,518,241 and 1,645,151 subjects aged 40 years or older in years 2010 and 2009, respectively. Late-stage CKD prevalence in year 2010 was used as a training set and its age-adjusted standardized morbidity rates (ASMR) were divided into three groups as defined <1.76%, 1.76% ≤ ASMR < 2.64%, and ≥2.64%, respectively. Year 2009, defined as the validation set, was used to validate the results. Results. The ASMR of late-stage CKD in years 2010 and 2009 were 1.76%, and 2.09%, respectively. Geographic variations were observed, with notably higher rates of disease in areas of the central, southwestern mountainside, and southeastern seaboard. There were no significant differences among different combined risk groups of RCC, UTUC, and LTUC incidence. Conclusion. The substantial geographic variations in the prevalence of late-stage CKD exist, but are not correlated with RCC, UTUC, or LTUC incidence.

Association of Vitamin E Intake with Reduced Risk of Kidney Cancer: A Meta-Analysis of Observational Studies

Background

Several observational studies suggested that vitamin E intake is related to the risk of kidney cancer; however, the results of published studies are inconsistent.

Material/Methods

A meta-analysis was performed to assess the relationship between vitamin E intake and the risk of kidney cancer by searching PubMed and Medline through August 2015. We computed pooled relative risks (RR) and 95%CI of kidney cancer for the highest versus lowest level of vitamin E intake.

Results

A total of 13 observational studies (7 case-control and 6 cohort) were included. The pooled RR (95%CI) of kidney cancer for the highest vs. the lowest level of vitamin E intake was 0.81 (0.69–0.94). In subgroup-analysis, this study found an inverse relationship between vitamin E intake and kidney cancer risk, which was not significantly modified by study design, study population, or sex distribution except in the cohort studies.

Conclusions

Results of the present study suggest an inverse relationship between vitamin E intake and kidney cancer risk. However, additional well designed cohort studies and randomized controlled trials that focus on the relationship between vitamin E intake and kidney cancer risk are needed.

Epidemiology and Trends in Incidence of Kidney Cancer in Iran

BACKGROUND

Kidney cancer has shown an increasing trend in recent decades. This study aimed to determine change in the incidence rate between 2003 and 2009 in Iran.

MATERIALS AND METHODS

In this study, national cancer registry data were used. Crude incidence rates were calculated per 100,000 and age-standardized incidence rates (ASRs) were computed using the direct standardization method and the world standard population. Significant trend of incidence rates was examined by the Cochran-Armitage test for linear trend.

RESULTS

A total of 6,944 cases of kidney cancer were reported. The incidence cases increased from 595 patients in 2003 to 1,387 patients in 2009. Sex ratio (male to female) was 1.67. ASR also increased from 1.18 in 2003 to 2.52 in 2009 per 100,000, but the increasing trend was not significant.

CONCLUSIONS

A slow increasing trend of incidence rate was observed in the study population. This may be due to an increase of risk factors. It is suggested to perform a study on risk factors for the cancer.

Vitamin E Intake and Risk of Renal Cell Carcinoma: A Meta-Analysis of 7 Case-Control Studies

OBJECTIVE

Vitamin E intake may reduce the risk of renal cell carcinoma, but the results were inconsistent. Hence, we conducted a meta-analysis to assess the association between dietary vitamin E intake and the risk of renal cell carcinoma.

METHODS

We searched PubMed to identify the relevant case-control studies up to June 2014. Reference lists of retrieved articles were also reviewed. Odds ratios and corresponding 95% confidence intervals were used to estimate the association between dietary vitamin E intake and the risk of renal cell carcinoma.

RESULTS

We identified 7 case-control studies regarding dietary vitamin E intake and risk of renal cell carcinoma, involving 5789 cases and 14866 controls. The odds ratio of renal cell carcinoma for the highest compared with the lowest dietary vitamin E intake was 0.75 (95% confidence interval: 0.59-0.91), and heterogeneity was observed across studies. The association between dietary vitamin E intake and the risk of renal cell carcinoma was not significantly differed by gender, but this association were inconsistent in the North American and European populations.

CONCLUSION

Our study provided a evidence that there was a significant inverse association of dietary vitamin E intake with risk of renal cell carcinoma. However, this finding was based on the case-control studies, more well-designed cohort studies are needed.

Hypertension and obesity and the risk of kidney cancer in 2 large cohorts of US men and women

Kidney cancer incidence is increasing globally. Reasons for this rise are unclear but could relate to obesity and hypertension. We analyzed longitudinal relationships between hypertension and obesity and kidney cancer incidence in 156 774 participants of the Women's Health Initiative clinical trials and observational studies over 10.8 years. In addition, we examined the effect of blood pressure (BP) on kidney cancer deaths for over 25 years among the 353 340 men screened for the Multiple Risk Factor Intervention Trial (MRFIT). In the Women's Health Initiative, systolic BP (SBP) was categorized in 6 groups from <120 to >160 mm Hg, and body mass index was categorized using standard criteria. In age-adjusted analyses, kidney cancer risk increased across SBP categories (P value for trend <0.0001) and body mass index categories (P value for trend <0.0001). In adjusted Cox proportional hazards models, both SBP levels and body mass index were predictors of kidney cancer. In the MRFIT sample, there were 906 deaths after an average of 25 years of follow-up attributed to kidney cancer among the 353 340 participants aged 35 to 57 years at screening. The risk of death from kidney cancer increased in a dose-response fashion with increasing SBP (hazard ratio, 1.87 for SBP>160 versus <120 mm Hg; 95% confidence interval, 1.38-2.53). Risk was increased among cigarette smokers. Further research is needed to determine the pathophysiologic basis of relationships between both higher BP and the risk of kidney cancer, and whether specific drug therapies for hypertension can reduce kidney cancer risk.

Kidney cancer incidence and mortality among American Indians and Alaska Natives in the United States, 1990-2009

OBJECTIVES

We describe rates and trends in kidney cancer incidence and mortality and identify disparities between American Indian/Alaska Native (AI/AN) and White populations.

METHODS

To improve identification of AI/AN race, incidence and mortality data were linked with Indian Health Service (IHS) patient records. Analysis focused on residents of IHS Contract Health Service Delivery Area counties; Hispanics were excluded. We calculated age-adjusted kidney cancer incidence (2001-2009) and death rates (1990-2009) by sex, age, and IHS region.

RESULTS

AI/AN persons have a 1.6 times higher kidney cancer incidence and a 1.9 times higher kidney cancer death rate than Whites. Despite a significant decline in kidney cancer death rates for Whites (annual percentage change [APC] = -0.3; 95% confidence interval [CI] = -0.5, 0.0), death rates for AI/AN persons remained stable (APC = 0.4; 95% CI = -0.7, 1.5). Kidney cancer incidence rates rose more rapidly for AI/AN persons (APC = 3.5; 95% CI = 1.2, 5.8) than for Whites (APC = 2.1; 95% CI = 1.4, 2.8).

CONCLUSIONS

AI/AN individuals have greater risk of developing and dying of kidney cancers. Incidence rates have increased faster in AI/AN populations than in Whites. Death rates have decreased slightly in Whites but remained stable in AI/AN populations. Racial disparities in kidney cancer are widening.

MALDI imaging mass spectrometry profiling of proteins and lipids in clear cell renal cell carcinoma

Reducing the incidence and mortality rates for clear cell renal cell carcinoma (ccRCC) remains a significant clinical challenge with poor 5-year survival rates. A unique tissue cohort was assembled of matched ccRCC and distal nontumor tissues (n = 20) associated with moderate risk of disease progression, half of these from individuals who progressed to metastatic disease and the other half who remained disease free. These tissues were used for MALDI imaging MS profiling of proteins in the 2-20 kDa range, resulting in a panel of 108 proteins that had potential disease-specific expression patterns. Protein lysates from the same tissues were analyzed by MS/MS, resulting in identification of 56 proteins of less than 20 kDa molecular weight. The same tissues were also used for global lipid profiling analysis by MALDI-FT-ICR MS. From the cumulative protein and lipid expression profile data, a refined panel of 26 proteins and 39 lipid species was identified that could either distinguish tumor from nontumor tissues, or tissues from recurrent disease progressors from nonrecurrent disease individuals. This approach has the potential to not only improve prognostic assessment and enhance postoperative surveillance, but also to inform on the underlying biology of ccRCC progression.

Obesity and hypertension interact to increase risk of renal cell carcinoma in Iowa, USA

SUMMARY

Renal cell carcinoma (RCC) rates in the US have risen, along with those of obesity and hypertension. We investigated the interactive relationship with obesity and hypertension (HT) through a population-based case-control study of RCC in Iowa consisting of 406 cases and 2434 controls. Data on height and weight at various ages and history of HT were collected and interaction tested by log-likelihood ratio tests. After adjustment, both obesity and HT were independently and interactively associated with increased RCC risk. Hypertensive subjects, obese (BMI ≥ 30) at age 40 were 4.2 (CI: 2.38-6.53) times more likely to develop RCC as normotensive individuals of normal weight (BMI < 25). A similar interactive pattern was observed for obesity at age 60 (p = 0.02). Interaction with obesity was more evident in women (pinteraction = 0.04 age 40, pinteraction = 0.01 age 60). Our findings suggest that maintaining body weight and/or controlling HT are strategies for preventing RCC.:

Dietary intake of nitrate and nitrite and risk of renal cell carcinoma in the NIH-AARP Diet and Health Study

BACKGROUND

Nitrate and nitrite are present in many foods and are precursors of N-nitroso compounds, known animal carcinogens and potential human carcinogens. We prospectively investigated the association between nitrate and nitrite intake from dietary sources and risk of renal cell carcinoma (RCC) overall and clear cell and papillary histological subtypes in the NIH-AARP Diet and Health Study.

METHODS

Nitrate and nitrite intakes were estimated from a 124-item food frequency questionnaire. Over a mean follow-up of 9 years, we identified 1816 RCC cases (n=498, clear cell; n=115, papillary cell) among 491 841 participants. Cox proportional hazard regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

Individuals in the highest quintile of nitrite intake from animal sources compared with those in the lowest quintile, had an increased risk of total RCC and clear cell subtype (HR=1.28, 95% CI, 1.10-1.49 and HR=1.68, 95% CI, 1.25-2.27, respectively). Nitrite from processed meats and other animal sources were associated with increased clear cell adenocarcinoma risk (HR=1.33, 95% CI, 1.01-1.76 and HR=1.78, 95% CI, 1.34-2.36, respectively). We found no association for nitrite intake from plant sources or nitrate intake overall.

CONCLUSION

Our findings suggest that nitrite from animal sources may increase the risk of RCC, particularly clear cell adenocarcinomas.

Blood pressure has only minor influence on aldosterone-induced oxidative stress and DNA damage in vivo

Epidemiological studies found an increased kidney cancer risk in hypertensive patients. These patients frequently present an increase in the mineralocorticoid aldosterone (Ald) due to a stimulated renin angiotensin aldosterone system (RAAS). Recently, we showed pro-oxidative and genotoxic effects of Ald in vitro. Here, we investigated the influence of blood pressure on aldosterone-induced oxidative damage. To distinguish whether effects in Sprague-Dawley rats treated with Ald were caused by Ald or by increased blood pressure, the mineralocorticoid receptor (MR) antagonist spironolactone was administered in a subtherapeutical dose, not lowering the blood pressure, and hydralazine, a RAAS-independent vasodilator, was given to normalize the pressure. With the antioxidant tempol, oxidative stress-dependent effects were demonstrated. Ald treatment caused kidney damage and oxidative and nitrative stress. Structural DNA damage and the mutagenic oxidative base modification 7,8-dihydro-8-oxoguanine were increased, as well as DNA repair activity and nuclear NF-κB translocation. Spironolactone and tempol decreased all markers significantly, whereas hydralazine had just slight effects. These data comprise the first report of essentially blood pressure-independent tissue- and DNA-damaging effects of Ald. A fully activated MR and the production of reactive oxygen and nitrogen species were crucial for these effects.

Alcohol drinking and risk of renal cell carcinoma: results of a meta-analysis

BACKGROUND

The role of alcohol consumption in relation with renal cell carcinoma is still unclear; a few studies have reported a beneficial effect of moderate levels of alcohol consumption, whereas it remains still under debate whether there is a dose-response association.

MATERIALS AND METHODS

Twenty observational studies (4 cohort, 1 pooled and 15 case-control) reporting results on at least three levels of alcohol consumption were selected through a combined search with PubMed and EMBASE of articles published before November 2010. Overall relative risks (RRs) and 95% confidence intervals (CIs) were estimated using random-effects models, and both second-order fractional polynomials and random effect meta-regression models were implemented for the study of dose-risk relation.

RESULTS

The estimated RRs were 0.85 (95% CI: 0.80-0.92) for any alcohol drinking, 0.90 (95% CI: 0.83-0.97) for light drinking (0.01-12.49 g/day), 0.79 (95% CI: 0.71-0.88) for moderate drinking (12.5-49.9 g/day) and 0.89 (95% CI: 0.58-1.39) for heavy drinking (≥50 g/day), respectively.

CONCLUSION

Our meta-analysis supports the hypothesis of a negative effect of moderate alcohol consumption on the risk of renal cell cancer.

HIV-induced kidney cell injury: role of ROS-induced downregulated vitamin D receptor

Reactive oxygen species (ROS) have been demonstrated to contribute to HIV-induced tubular cell injury. We hypothesized that HIV-induced ROS generation may be causing tubular cell injury through downregulation of vitamin D receptor (VDR) and associated downstream effects. In the present study, HIV not only downregulated tubular cell VDR expression but also inflicted DNA injury. On the other hand, EB-1089, a VDR agonist (VD), inhibited both downregulation of VDR and tubular cell DNA injury in the HIV milieu. H(2)O(2) (an O(-) donor) directly downregulated tubular cell VDR, whereas catalase, a free radical scavenger, inhibited HIV-induced downregulation of tubular cell VDR expression. HIV also stimulated the tubular cell renin-angiotensin system (RAS) through downregulation of VDR. Because losartan (an ANG II blolcker) partially inhibited HIV-induced tubular cell ROS generation while ANG II directly stimulated tubular cell ROS generation, it appears that HIV-induced ROS production was partly contributed by the RAS activation. VD not only inhibited HIV-induced RAS activation but also attenuated tubular cell ROS generation. Tubular cells displayed double jeopardy in the HIV milieu induction of double-strand breaks and attenuated DNA repair; additionally, in the HIV milieu, tubular cells exhibited enhanced expression of phospho-p53 and associated downstream signaling. A VDR agonist and an ANG II blocker not only preserved expression of tubular cell DNA repair proteins but also inhibited induction of double-strand breaks. In in vivo studies, renal cortical sections of Tg26 mice displayed attenuated expression of VDR both in podocytes and tubular cells. In addition, renal cortical sections of Tg26 mice displayed enhanced oxidative stress-induced kidney cell DNA damage. These findings indicated that HIV-induced tubular cell downregulation of VDR contributed to the RAS activation and associated tubular cell DNA damage. However, both VD and RAS blockade provided protection against these effects of HIV.

Environmental and modifiable risk factors in renal cell carcinoma

OBJECTIVES

Prevention of disease requires a firm understanding of the relevant environmental and modifiable risk factors. We present a comprehensive review of these factors in renal cell carcinoma.

MATERIALS AND METHODS

A literature search of the PubMed database was performed to identify clinical studies examining the relationship between environmental and modifiable factors in the development of renal cell carcinoma (terms utilized: kidney cancer; renal cell carcinoma; risk factors; environment; obesity; hypertension; trichloroethylene). An emphasis was placed on more recent studies.

RESULTS

Case control and large cohort studies have examined the relationship of numerous environmental and modifiable factors and the risk of renal cell carcinoma. Of particular note are dose-dependent increases in smokers, the obese, and hypertensive patients.

CONCLUSIONS

Environmental and modifiable risk factors contribute significantly to the risk of sporadic renal cell carcinoma. Emphasis should be placed on smoking cessation and hypertension control. Emerging evidence would suggest that dietary intake and quality impact renal cell carcinoma risk.

Lead, calcium uptake, and related genetic variants in association with renal cell carcinoma risk in a cohort of male Finnish smokers

BACKGROUND

Lead is classified as a probable human carcinogen. However, its role in renal cell cancer (RCC) has not been established. Calcium and vitamin D may off-set toxicity in vivo.

METHODS

In this nested case-control study, whole blood lead, total serum calcium, and serum 25-hydroxyvitamin D levels were measured in blood drawn prior to diagnosis among male smokers participating in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study. Single-nucleotide polymorphisms (SNP) in five genes (CALB1, TRPV5, TRPV6, VDR, and ALAD) related to lead toxicity or calcium transport were genotyped. Logistic and linear regressions were used to determine RCC risk and time to diagnosis (respectively), adjusting for other risk factors.

RESULTS

Among 154 newly diagnosed cases and 308 matched controls, RCC was associated with higher whole blood lead [OR = 2.0; 95% confidence interval (CI), 1.0-3.9; quartile 4 (Q4) vs. Q1, P(trend) = 0.022] and CALB1 rs1800645 (P(trend) = 0.025, minor 'T' allele frequency = 0.34). Higher total serum calcium (P(trend) ≤ 0.001) was associated with reduced RCC risk. Total serum calcium and 25-hydroxyvitamin D levels did not alter the association observed with lead. Time from enrollment to RCC diagnosis was positively associated with serum calcium (P(trend) = 0.002) and 25-hydroxyvitamin D (P(trend) = 0.054) among cases.

CONCLUSIONS

Higher blood lead concentrations, below the 10 μg/dL level of concern, were associated with RCC, independent from serum calcium and CALB1 promoter polymorphism.

IMPACT

Increased risk of RCC is associated with lower serum calcium and higher whole blood lead in smokers. The clinical prognostic value of serum calcium and vitamin D in RCC should be further investigated.

Fruit, vegetables, fibre and micronutrients and risk of US renal cell carcinoma

The association between renal cell cancer (RCC) and intake of fruit, vegetables and nutrients was examined in a population-based case-control study of 323 cases and 1827 controls; dietary intake was obtained using a mailed questionnaire. Cancer risks were estimated by OR and 95 % CI, adjusting for age, sex, smoking, obesity, hypertension, proxy status, alcohol consumption and dietary fat intake and energy. Intake of vegetables was associated with a decreased risk of RCC (OR 0·5; 95 % CI 0·3, 0·7; P trend = 0·002), (top compared to the bottom quartile of intake). When intake of individual nutrients was investigated, vegetable fibre intake was associated with decreased risks (OR 0·4; 95 % CI 0·2, 0·6; P < 0·001), but this was not the case with fruit fibre (OR 0·7; 95 % CI 0·4, 1·1) or grain fibre (OR 1·0; 95 % CI 0·6, 1·5). β-Cryptoxanthin and lycopene were also associated with decreased risks, but when both were included in a mutually adjusted backwards stepwise regression model, only β-cryptoxanthin remained significant (OR 0·5; 95 % CI 0·3, 0·8). When other micronutrients and types of fibre were investigated together, only vegetable fibre and β-cryptoxanthin had significant trends (P < 0·01) (OR 0·6; 95 % CI 0·3, 0·9) (OR 0·5; 95 % CI 0·3, 0·9), respectively. These findings were stronger in those aged over 65 years (P interaction = 0·001). Among non-smokers, low intake of cruciferous vegetables and fruit fibre was also associated with increased risk of RCC (P interaction = 0·03); similar inverse associations were found for β-cryptoxanthin, lycopene and vitamin C. When nutrients were mutually adjusted by backwards regression in these subgroups, only β-cryptoxanthin remained associated with lower RCC risk. These findings deserve further investigation in ongoing prospective studies when sample size becomes sufficient.

Aldosterone increases kidney tubule cell oxidants through calcium-mediated activation of NADPH oxidase and nitric oxide synthase

Chronic hyperaldosteronism has been associated with an increased cancer risk. We recently showed that aldosterone causes an increase in cell oxidants, DNA damage, and NF-κB activation. This study investigated the mechanisms underlying aldosterone-induced increase in cell oxidants in kidney tubule cells. Aldosterone caused an increase in both reactive oxygen and reactive nitrogen (RNS) species. The involvement of the activation of NADPH oxidase in the increase in cellular oxidants was demonstrated by the inhibitory action of the NADPH oxidase inhibitors DPI, apocynin, and VAS2870 and by the migration of the p47 subunit to the membrane. NADPH oxidase activation occurred as a consequence of an increase in cellular calcium levels and was mediated by protein kinase C. The prevention of RNS increase by BAPTA-AM, W-7, and L-NAME indicates a calcium-calmodulin activation of NOS. A similar pattern of effects of the NADPH oxidase and NOS inhibitors was observed for aldosterone-induced DNA damage and NF-κB activation, both central to the pathogenesis of chronic aldosteronism. In summary, this paper demonstrates that aldosterone, via the mineralocorticoid receptor, causes an increase in kidney cell oxidants, DNA damage, and NF-κB activation through a calcium-mediated activation of NADPH oxidase and NOS. Therapies targeting calcium, NOS, and NADPH oxidase could prevent the adverse effects of hyperaldosteronism on kidney function as well as its potential oncogenic action.

The association between renal cell carcinoma and multiple myeloma: insights from population-based data

OBJECTIVE

• To evaluate the hypothesis of an association between renal cell carcinoma and multiple myeloma.

PATIENTS AND METHODS

• Data from nine population-based registries in the Surveillance, Epidemiology and End Results programme were used to evaluate two separate cohorts of patients diagnosed between 1973 and 2006: patients diagnosed with renal cell carcinoma as a primary malignancy (n= 57,190) and patients diagnosed with multiple myeloma as a primary malignancy (n= 34,156). • We estimated standardized incidence ratios (SIRs) with corresponding 95% confidence intervals (CIs) by dividing the number of observed cases of multiple myeloma within the renal cell carcinoma cohort and the number of renal cell carcinoma cases within the multiple myeloma cohort by the number of expected cases for each malignancy in the US general population.

RESULTS

• The renal cell carcinoma cohort yielded 88 multiple myeloma cases during 293,511 person-years of follow up. Patients with renal cell carcinoma had a higher relative risk of multiple myeloma than the general population (SIR = 1.51, 95% CI 1.21-1.85). • The multiple myeloma cohort yielded 69 renal cell carcinoma cases during 100,804 person-years of follow up. Patients with multiple myeloma had a higher relative risk of renal cell carcinoma than the general population (SIR = 1.89, 95% CI 1.47-2.40).

CONCLUSION

• Our analyses revealed a bidirectional association between renal cell carcinoma and multiple myeloma, which typically indicates shared risk factors.

The non-neoplastic kidney in tumor nephrectomy specimens: what can it show and what is important?

Surgical nephrectomy is a procedure that has been performed for nearly 100 years. In the presence of a normal contralateral kidney, such as in a renal transplant donor or child with Wilms tumor, it is a benign procedure without deleterious consequences on the remaining kidney. However, many adults and some children postnephrectomy will develop chronic kidney disease. The non-neoplastic kidney in tumor resections may harbor a large number of developmental and acquired diseases predictive of this outcome or that convey other medically significant information. Examination of the non-neoplastic kidney is a fertile opportunity to identify these unsuspected conditions that may ultimately dictate the subsequent clinical course and influence the medical care provided. This review discusses the consequences of unilateral and partial nephrectomy, and illustrates many conditions that may be encountered in the non-neoplastic cortex with a discussion of their clinical implications.

Everolimus: the first approved product for patients with advanced renal cell cancer after sunitinib and/or sorafenib

Everolimus (RAD001, Afinitor^® Novartis) is the first oral inhibitor of mTOR (mammalian target of rapamycin) to reach the oncology clinic. Everolimus 10 mg daily achieves complete inhibition of its target at below the maximum tolerable dose for most patients. A phase III randomized placebo-controlled trial has examined the impact of everolimus in patients with clear cell renal cancers and progressive disease on or within 6 months of the VEGFR tyrosine kinase inhibitors sunitinib and/or sorafenib. The primary endpoint of progression-free survival was increased from median 1.9 to 4.9 months (hazard ratio 0.33, P < 0.001) and 25% were still progression-free after 10 months of everolimus therapy. There was a delay in time to decline of performance status and trends to improvement in quality of life, disease-related symptoms, and overall survival despite crossover of the majority of patients assigned to placebo. In 2009, everolimus was approved in the US and Europe as the only validated option for this indication. Toxicities are usually mild to moderate and can be managed with dose reduction or interruption if necessary. Opportunistic infections and non-infectious pneumonitis are seen as a class effect. Management of common practical management issues are discussed. Clinical trials are in progress to examine additional roles for everolimus in renal cancer, alone and in combination with other agents.

A prospective study of one-carbon metabolism biomarkers and risk of renal cell carcinoma

OBJECTIVE

Previous studies have found associations between one-carbon metabolism factors and risk of several cancers, but little is known regarding renal cell carcinoma (RCC). We conducted a nested case-control study within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study, a prospective study of Finnish male smokers aged 50-69 at baseline.

METHODS

Prediagnostic folate, vitamin B(6), vitamin B(12), cysteine, riboflavin, and homocysteine concentrations were measured in fasting serum from 224 incident RCC cases and 224 controls (matched on age and date of serum collection). Conditional logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for potential confounders.

RESULTS

Serum folate tended to be inversely associated with RCC, compared to the first quartile, the odds ratios (95% CI) for subsequent quartiles were 0.62 (0.35-1.08), 0.52 (0.29-0.93), and 0.67 (0.37-1.20) (P-trend = 0.19). When modeled as a threshold effect, subjects in the lowest serum folate quartile (<or=6.64 nmol/l), which corresponds to deficient folate status, had a significant increased RCC risk (OR = 1.68, 95% CI 1.06-2.65) compared to those with higher serum folate. The other one-carbon metabolism biomarkers were not associated with RCC.

CONCLUSIONS

This study in male smokers suggests that deficient folate status may increase risk of RCC, but confirmation is needed in other epidemiologic studies that include women and non-smokers.

Kidney cancer mortality: fifty-year latency patterns related to arsenic exposure

BACKGROUND

Arsenic in drinking water is associated with kidney cancer. Beginning in 1958, a region of Chile experienced a rapid onset of high arsenic exposure in drinking water, followed by sharp declines when water treatment plants were installed in 1971.

METHODS

For the years 1950-1970, we obtained mortality data from death certificates for an exposed region and an unexposed region in Chile. We obtained computerized mortality data for all of Chile for 1971-2000.

RESULTS

Kidney cancer risks for the exposed region compared with the unexposed started to increase about 10 years after high arsenic exposures began in 1958. The peak kidney cancer mortality rate ratio (RR) was 3.4 (95% confidence interval = 2.2-5.1) for men in 1981-1985, with subsequent declines to 1.6 (1.2-2.1) by 1996-2000. Mortality RRs among women were 2.9 (1.8-4.7) in 1981-1985 but remained high longer than for men, increasing further to a RR of 4.4 (3.0-6.4) in 1991-1995. Early-life exposure resulted in an increased RR of 7.1 (3.1-14) for young adults aged 30-39 years, born just before or during the high exposure period.

CONCLUSIONS

This study shows a latency pattern of increased mortality from kidney cancer, continuing for at least 25 years after the high exposures began to decline. Early life exposure resulted in markedly higher kidney cancer mortality in young adults.

No association between fruit, vegetables, antioxidant nutrients and risk of renal cell carcinoma

Previous epidemiologic studies that have examined the relationship between renal cell carcinoma (RCC) risk and intakes of plant foods and antioxidant nutrients have yielded inconsistent results. We therefore examined the associations between intakes of fruit, vegetables, carotenoids, flavonoids, vitamin E and vitamin C and RCC risk in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study cohort. At baseline, 27,062 male Finnish smokers aged 50-69 years completed a 276-item dietary questionnaire that included questions on frequency of consumption and portion size. During up to 19 years of follow-up, 255 men developed RCC. Cox proportional hazards models were utilized to estimate relative risks (RR) and 95% confidence intervals (CI). Despite a large range in intake, no association was observed between fruit, vegetables or antioxidant nutrients and RCC risk. For example, multivariate RRs and 95% CIs for the highest versus the lowest quartile of intake were 0.79 (0.55-1.14), 1.23 (0.85-1.79), 1.09 (0.74-1.60), 0.83 (0.57-1.21), 1.09 (0.73-1.64) and 0.99 (0.67-1.46) for fruit, vegetables, total carotenoids, total flavonoids, total vitamin E and vitamin C, respectively (all p values for trend > 0.05). Our results indicate that diet may not play a large role in the etiology of RCC in male smokers, although further examination of these associations in nonsmokers, women and diverse racial populations is warranted.