International renal-cell-cancer study. VI. the role of medical and family history

Influenza vaccination is associated with lower risk of renal cell carcinoma among chronic kidney disease patients: a population-based cohort study

Background

Chronic kidney disease (CKD) patients possess a higher risk for renal cell carcinoma (RCC) possibly because of related underlying inflammation and immune dysregulation. In the current population-based cohort study, we evaluate the effects of influenza vaccination on RCC among CKD patients.

Methods

We analysed the vaccinated and unvaccinated CKD patients (≥55 years of age) identified from the Taiwan National Health Insurance Database. Propensity score matching was used to reduce the selection bias. Subgroup analyses based on comorbid conditions, dialysis status and vaccinated dosages were also conducted.

Results

The incidence of RCC decreased significantly in the vaccinated compared with unvaccinated group {unadjusted hazard ratio [HR] 0.50 [95% confidence interval (CI) 0.31-0.81], P < .01; adjusted HR 0.46 [95% CI 0.28-0.75], P < .01}. Such protective effects of influenza vaccination were noted significantly among those ≥75 years of age [unadjusted HR 0.29 (95% CI 0.12-0.74), P < .01; adjusted HR 0.22 (95% CI 0.08-0.58), P < .01]. A reverse association was noted between the total number of vaccinations and RCC events in both unadjusted and adjusted models. The Kaplan-Meier estimates of the RCC events showed significantly higher free survival rates in the vaccinated as compared with the unvaccinated patients (logrank P = .005).

Conclusion

This population-based cohort study found a significant inverse relationship between influenza vaccination and the risk of RCC in CKD patients and the protective effects were more prominent in patients >75 years of age. A possible relation exists between the total number of vaccinations and RCC events. Future randomized clinical and basic studies will be needed to prove these findings and underlying pathophysiological mechanisms.

Association Between Diabetes and the Risk of Kidney Cancer: Systematic Review and Meta-Analysis

Diabetes is a risk factor for several types of cancer, but the specific relationship between diabetes and kidney cancer is not well understood. We conducted a search strategy in scientific databases for case-control and cohort studies on this topic. We analyzed 17 studies and found that diabetes was significantly associated with the risk of developing kidney cancer and that this risk was slightly stronger for women and for people living in Asia. These findings were not influenced by obesity, cigarette smoking, or hypertension. We conclude that diabetes is an independent risk factor for the development of kidney cancer.

The influence of dysbiosis on kidney stones that risk up renal cell carcinoma (RCC)

Kidney stone is a common urological condition, the prevalence and incidence of which has escalated in the last few years due to dietary habits and other related medical conditions such as obesity and diabetes mellitus. It is a chronic disease which leads to loss of kidney function(s) and nephrectomy. Chronic kidney stone disease has been shown to be associated with transitional cell carcinoma (TCC) or renal cell carcinoma (RCC) and kidney tumors have been found to be more frequent among patients with kidney stones. Although hyperoxaluria is mainly responsible for kidney stone formation, dysbiosis of the gut and urinary tract microbiome may in part contribute to kidney stone disease. Dysbiosis of the gut and urinary tract microbiome have been linked to kidney stone diseases with both gain and loss of function. The review provides a detailed study of how the variations in the microbiome of the human gut and urinary tract result in the chronic kidney stone diseases which are associated with increased papillary RCC risks.

Interaction of germline variants in a family with a history of early-onset clear cell renal cell carcinoma

Background

Identification of genetic factors causing predisposition to renal cell carcinoma has helped improve screening, early detection, and patient survival.

Methods

We report the characterization of a proband with renal and thyroid cancers and a family history of renal and other cancers by whole‐exome sequencing (WES), coupled with WES analysis of germline DNA from additional affected and unaffected family members.

Results

This work identified multiple predicted protein‐damaging variants relevant to the pattern of inherited cancer risk. Among these, the proband and an affected brother each had a heterozygous Ala45Thr variant in SDHA, a component of the succinate dehydrogenase (SDH) complex. SDH defects are associated with mitochondrial disorders and risk for various cancers; immunochemical analysis indicated loss of SDHB protein expression in the patient’s tumor, compatible with SDH deficiency. Integrated analysis of public databases and structural predictions indicated that the two affected individuals also had additional variants in genes including TGFB2, TRAP1, PARP1, and EGF, each potentially relevant to cancer risk alone or in conjunction with the SDHA variant. In addition, allelic imbalances of PARP1 and TGFB2 were detected in the tumor of the proband.

Conclusion

Together, these data suggest the possibility of risk associated with interaction of two or more variants.

Kidney stones and the risk of renal cell carcinoma and upper tract urothelial carcinoma: the Netherlands Cohort Study

Background

We examined the association between kidney stones and renal cell carcinoma (RCC) and upper tract urothelial carcinoma (UTUC) risk in the Netherlands Cohort Study on diet and cancer.

Methods

In total, 120,852 participants aged 55–69 completed a self-administered questionnaire on diet, medical conditions and other risk factors for cancer at baseline (1986). After 20.3 years of cancer follow-up 4352 subcohort members, 544 RCC cases and 140 UTUC cases were eligible for case-cohort analysis. Hazard ratios (HR) and 95% confidence intervals (CIs) were estimated by multivariable-adjusted proportional hazards models.

Results

Kidney stones were associated with an increased RCC risk (HR: 1.39, 95% CI 1.05–1.84), vs. no kidney stones. Kidney stones were associated with an increased risk of papillary RCC (HR: 3.08, 95% CI 1.55–6.11), but not clear-cell RCC (HR: 1.14, 95% CI 0.79–1.65). UTUC risk was increased for participants with kidney stones (HR: 1.66, 95% CI 1.03–2.68). No heterogeneity of associations was found for UTUC in the ureter and renal pelvis. An early kidney stone diagnosis (≤40 years) was associated with an increased RCC and UTUC risk, compared to later diagnosis.

Conclusion

Kidney stones were associated with increased papillary RCC risk, but not clear-cell RCC risk. No heterogeneity was found for UTUC subtypes.

Genetic scores based on risk-associated single nucleotide polymorphisms (SNPs) can reveal inherited risk of renal cell carcinoma

The objective of this study was to evaluate whether renal cell carcinoma (RCC) risk-associated single nucleotide polymorphisms (SNPs) could reflect the individual inherited risks of RCC. A total of 346 RCC patients and 1,130 controls were recruited in this case-control study. Genetic scores were calculated for each individual based on the odds ratios and frequencies of risk-associated SNPs. Four SNPs were significantly associated with RCC in Chinese population. Two genetic score models were established, genetic score 1 (rs10054504, rs7023329 and rs718314) and genetic score 2 (rs10054504, rs7023329 and rs1049380). For genetic score 1, the individual likelihood of RCC with low (<0.8), medium (0.8-1.2) and high (≥1.2) genetic score 1 was 15.61%, 22.25% and 33.92% respectively (P-trend=6.88×10(-7)). For genetic score 2, individual with low (<0.8), medium (0.8-1.2) and high (≥1.2) genetic score 2 would have likelihood of RCC as 14.39%, 24.54% and 36.48%, respectively (P-trend=1.27×10(-10)). The area under the receiver operating curve (AUC) of genetic score 1 was 0.626, and AUC of genetic score 2 was 0.658. We concluded that genetic score can reveal personal risk and inherited risk of RCC, especially when family history is not available.

Inherited Forms of Renal Cell Carcinoma

It is estimated that up to 2% of renal cell cancer (RCC) clusters in families. Several forms of hereditary RCC have been characterized with specific clinical, histopathological, and genetic features. The most common of these is von Hippel-Lindau (VHL) disease caused by mutations in the VHL gene and predisposing to clear cell RCC. Predisposition to papillary RCC is present in hereditary leiomyomatosis and renal cell cancer (HLRCC) and hereditary papillary renal cell carcinoma (HPRC). Identification of the genetic defects causing these diseases has enlightened the molecular pathogenesis of RCC, and moreover, provided means to improve patient management. Genetic testing enables early diagnosis of the disease, after which individuals at-risk can be guided to regular surveillance. Screening facilitates detection of presymptomatic early tumors broadening treatment options and potentially improving prognosis. Thus, identification of individuals with inherited cancer susceptibility is important as special management of these patients improves disease outcome. The purpose of this review is to provide clues for identification and management of hereditary renal cancer patients in clinical practice.

Epidemiology of Renal Cell Carcinoma

The increasing incidence of RCC in most populations may in part be due to increasing numbers of incidentally detected cancers with new imaging methods. Further, the increase is not only limited to small local tumours but also includes more advanced tumours, which may to some part explain the still high mortality rates. The variation in incidence between populations may have several other explanations. Traditionally the starting point has included thoughts of environmental exposures, which so far have only in part explained the causes of RCC, by means of cigarette smoking and obesity, which may account for approximately 40% of cases in high-risk countries (Table 2). Further, the genetic variations may be of importance as a cause of the difference between populations. Continued research in RCC is needed with the knowledge that nearly 50% of patients die within 5 years after diagnosis. The further search for environmental exposures should take in account the knowledge that RCC consists of different types with specific genetic molecular characteristics. These genetic alterations have in some cases been suggested to be associated with specific exposures. Furthermore, there might exist a modulating effect of genetic polymorphisms among metabolic activation and detoxification enzymes. Hence, a further understanding of the genetic and molecular processes involved in RCC will hopefully give us a better knowledge how to analyse and interpret exposure associations that have importance for both initiation and progression of RCC.

Chronic oxidative stress leads to malignant transformation along with acquisition of stem cell characteristics, and epithelial to mesenchymal transition in human renal epithelial cells

Oxidative injury to cellular macromolecules has been suggested as a common pathway shared by multiple etiological factors for kidney cancer. Whether the chronic oxidative stress alone is sufficient to induce malignant transformation in human kidney cells is not clear. Therefore, the objective of this study was to evaluate the effect of H2O2-induced chronic oxidative stress on growth, and malignant transformation of HK-2 normal kidney epithelial cells. This study revealed that chronic oxidative stress causes increased growth and neoplastic transformation in normal kidney epithelial cells at non-cytotoxic dose and increased adaptation to cytotoxic level. This was confirmed by gene expression changes, cell cycle analysis, anchorage independent growth assay and in vivo tumorigenicity in nude mice. Stem cells characteristics as revealed by up-regulation of stem cell marker genes, and morphological changes indicative of EMT with up regulation of mesenchymal markers were also observed in cells exposed to chronic oxidative stress. Antioxidant NAC did not reverse the chronic oxidative stress-induced growth, and adaptation suggesting that perturbed biological function in these cells are permanent. Partial reversal of oxidative stress-induced growth, and adaptation by silencing of Oct 4 and Snail1, respectively, suggest that these changes are mediated by acquisition of stem cell and EMT characteristics. In summary, this study for the first time suggests that chronic exposure to elevated levels of oxidative stress is sufficient to induce malignant transformation in kidney epithelial cells through acquisition of stem cell characteristics. Additionally, the EMT plays an important role in increased adaptive response of renal cells to oxidative stress.

The risk of kidney cancer in patients with kidney stones: a systematic review and meta-analysis

BACKGROUND

The objective of this meta-analysis was to evaluate the association between a history of kidney stones and kidney cancer.

METHODS

A literature search was performed from inception until June 2014. Studies that reported odds ratios or hazard ratios comparing the risk of renal cell carcinoma (RCC) and transitional cell carcinoma (TCC) of the upper urinary tract in patients with the history of kidney stones versus those without the history of kidney stones were included. Pooled risk ratios (RRs) and 95% confidence interval (CI) were calculated using a random-effect, generic inverse variance method.

RESULT

Seven studies were included in our analysis to assess the association between a history of kidney stones and RCC. The pooled RR of RCC in patients with kidney stones was 1.76 (95% CI, 1.24-2.49). The subgroup analysis found that the history of kidney stones was associated with increased RCC risk only in males (RR, 1.41 [95% CI, 1.11-1.80]), but not in females (RR, 1.13 [95% CI, 0.86-1.49]). Five studies were selected to assess the association between a history of kidney stones and TCC. The pooled RR of TCC in patients with kidney stones was 2.14 (95% CI, 1.35-3.40).

CONCLUSION

Our study demonstrates a significant increased risk of RCC and TCC in patients with prior kidney stones. However, the increased risk of RCC was noted only in male patients. This finding suggests that a history of kidney stones is associated with kidney cancer and may impact clinical management and cancer surveillance.

Transient ischaemic attack secondary to paraneoplastic erythrocytosis

A 67-year-old woman with a history of hypertension and type 2 diabetes mellitus was admitted to the hospital due to aphasia and left-sided hemiparesis during the past 5 h with resolution of symptoms within 24 h. On admission laboratory analysis showed haemoglobin 19.2 g/dL and haematocrit 55.1%. Cerebral CT scan was also performed on admission revealing periventricular leucoaraiosis. Studies to investigate the cause of erythrocytosis were started and elevated erythropoietin levels were found. In order to investigate a secondary cause of erythrocytosis an abdominal ultrasound was conducted revealing a left renal mass. CT scans of thorax, abdomen and pelvis confirmed renal mass 8 × 8 cm of diameter, suggestive of neoplasm without associated lymphadenopathy or metastases. Radical nephrectomy was performed and a pathological diagnosis demonstrated clear cell renal cell carcinoma and was staged as T2aN0M0.

Evaluation of ABO blood group as a prognostic marker in renal cell carcinoma (RCC)

OBJECTIVE

To evaluate ABO blood group as a prognostic marker in patients with renal cell carcinoma (RCC).

PATIENTS AND METHODS

This retrospective study included 556 consecutive patients who underwent surgery for RCC at a single institution. The associations of ABO blood group with clinical and pathological variables were assessed using Kruskal-Wallis and chi-squared tests. The impact on overall survival (OS) and RCC-specific survival (RCC-SS) was analysed using univariable and multivariable Cox proportional hazards regression models.

RESULTS

Blood group O was associated with the absence of lymph node metastases (P = 0.034) and the presence of bilateral RCC (P = 0.017). No associations with age, gender, body mass index, Charlson comorbidity index, T stage, M stage, grade and histological subtype were observed. In univariable and multivariable survival analysis, ABO blood group was not associated with OS and RCC-SS.

CONCLUSIONS

In the present study, ABO blood group was not linked with RCC prognosis. Blood group O may be associated with the absence of lymph node metastases and the presence of bilateral RCC. External validation in larger cohorts is necessary.

A population-based study on the association between urinary calculi and kidney cancer

BACKGROUND

Using a nationwide population-based dataset and case-control study design, we investigate the association between urinary calculi (UC) and kidney cancer (KC) in Taiwan.

METHODS

The data for this case-control study were sourced from the Taiwan National Health Insurance program. The cases included 1308 incident patients pathologically diagnosed with KC. This study also used 6540 randomly selected subjects as controls. Conditional logistic regression was used to examine the associations between KC and patients previously diagnosed with UC.

RESULTS

Of the sampled patients, 1262 (16.1 %) had previously been diagnosed with UC; 415 (31.7 % of the patients with KC) and 847 controls (13.0 % of patients without KC). After adjusting for monthly income, geographic location, urbanization level, hypertension, diabetes, renal disease, obesity, cystic kidney disease, tobacco use disorder, and alcohol abuse, we found that patients with KC were likely to have been previously diagnosed with UC than controls (odds ratio [OR] 3.18, 95% confidence interval [CI] 2.75-3.68, p < 0.001). In addition, the magnitude of the observed associations were stronger among females (females OR 3.59; 95% CI 2.87-4.48 vs. males OR 2.93, 95% CI 2.42-3.55) and transitional cell carcinoma patients (transitional cell carcinoma, OR 3.96; 95% CI 3.23-4.86 vs. renal cell carcinoma OR 2.76, 95% CI 2.31-3.29).

CONCLUSIONS

We conclude that there is an association between KC and prior UC, especially in females and patients with transitional cell carcinoma.

Kidney Cancer and Diabetes Mellitus: A Population-Based Case-Control Study in Taiwan

Introduction: The purpose of this study was to explore whether diabetes mellitus (DM) correlates with the risk of kidney cancer in Taiwan. Materials and Methods: We designed a population-based case-control study from the Taiwan National Health Insurance Database, which consisted of 116 patients with newly diagnosed kidney cancer as cases and 464 subjects without kidney cancer as controls in 2000 to 2009. Both cases and controls were aged ≥20 years. Baseline comorbidities were compared between kidney cancer cases and controls. Results: Multivariable analysis showed no association was detected between DM and kidney cancer (OR 1.06, 95% CI, 0.58 to 1.94). Hypertension (OR 2.05, 95% CI, 1.23 to 3.42), chronic kidney diseases (OR 2.57, 95% CI, 1.23 to 5.37), cystic kidney diseases (OR 18.6, 95% CI, 1.84 to 187.6) and kidney stones (OR 4.02, 95% CI, 2.43 to 6.66) were significant comorbidities associated with increased risk of kidney cancer. Use of alpha-glucosidase inhibitor was associated with increased risk of kidney cancer (OR 4.31, 95% CI, 1.07 to 17.3). Conclusion: DM does not correlate with the risk of kidney cancer. Hypertension, chronic kidney diseases, cystic kidney diseases, kidney stones and use of alpha-glucosidase inhibitors are associated with kidney cancer. Key words: Chronic kidney disease, Cystic kidney disease, Diabetes mellitus, Hypertension, Kidney cancer, Kidney stone

Energy balance, polymorphisms in the mTOR pathway, and renal cell carcinoma risk

BACKGROUND

The interplay between obesity, physical activity, weight gain, and genetic variants in the mTOR pathway has not been studied in renal cell carcinoma (RCC). We examined the associations between obesity, weight gain, physical activity, and RCC risk. We also analyzed whether genetic variants in the mTOR pathway could modify the association.

METHODS

Incident RCC case subjects and healthy control subjects were recruited from the University of Texas MD Anderson Cancer Center in Houston, Texas. Case subjects and control subjects were frequency matched. Epidemiologic data were collected by in-person interview. One hundred ninety single nucleotide polymorphisms (SNPs) from 22 genes in the mTOR pathway were extracted from previous genome-wide association studies. Logistic regression and regression spline were performed to obtain odds ratios (ORs). All statistical tests were two-sided.

RESULTS

A total of 577 non-Hispanic white case subjects and 593 healthy control subjects were included. Obesity at age 20 years (OR = 1.92, 95% confidence interval [CI] = 1.05 to 3.50; P = .03) and age 40 years (OR = 2.03, 95% CI = 1.38 to 2.98; P < .001) and moderate (OR = 1.46, 95% CI = 1.02 to 2.09; P = .04) and massive weight gain (OR = 1.62, 95% CI = 1.10 to 2.39; P = .01) from age 20 to 40 years were each statistically significantly associated with increased RCC risk. Low physical activity was associated with a 4.08-fold increased risk. Among 190 SNPs in the mTOR pathway, six SNPs located in the AKT3 gene were statistically significantly associated with increased risk, and those with three or more unfavorable genotypes had a 1.72-fold increased risk of RCC.

CONCLUSION

Obesity, weight gain, physical activity, and genetic variants in the mTOR pathway may individually and jointly influence susceptibility to RCC.

The chromosome 2p21 region harbors a complex genetic architecture for association with risk for renal cell carcinoma

In follow-up of a recent genome-wide association study (GWAS) that identified a locus in chromosome 2p21 associated with risk for renal cell carcinoma (RCC), we conducted a fine mapping analysis of a 120 kb region that includes EPAS1. We genotyped 59 tagged common single-nucleotide polymorphisms (SNPs) in 2278 RCC and 3719 controls of European background and observed a novel signal for rs9679290 [P = 5.75 × 10(-8), per-allele odds ratio (OR) = 1.27, 95% confidence interval (CI): 1.17-1.39]. Imputation of common SNPs surrounding rs9679290 using HapMap 3 and 1000 Genomes data yielded two additional signals, rs4953346 (P = 4.09 × 10(-14)) and rs12617313 (P = 7.48 × 10(-12)), both highly correlated with rs9679290 (r(2) > 0.95), but interestingly not correlated with the two SNPs reported in the GWAS: rs11894252 and rs7579899 (r(2) < 0.1 with rs9679290). Genotype analysis of rs12617313 confirmed an association with RCC risk (P = 1.72 × 10(-9), per-allele OR = 1.28, 95% CI: 1.18-1.39) In conclusion, we report that chromosome 2p21 harbors a complex genetic architecture for common RCC risk variants.

Diabetes and risk of renal cell carcinoma

Background and objectives: There is evidence that the incidence of solid tumors is markedly increased in patients with diabetes mellitus. In the current study, we investigate the association between diabetes and renal cancer.

Patients and Methods: A single-center retrospective analysis of 473 patients who underwent nephrectomy for renal cell carcinoma (RCC) was performed. Diabetic RCC patients were screened for age, gender, ethnicity, HgA1C, glucose levels and renal function.

Results: Of the 473 cases with RCC, we identified 120 patients (25.4%) with a history of diabetes. The incidence of diabetes in RCC patients was higher in female than male subjects and in Hispanic compared to White and Other ethnic backgrounds. At diagnosis, the majority of diabetic RCC patients were 50-59 years of age. In diabetic RCC cases, clear cell type histology (92.0%), nuclear grade 2 (56.1%) and tumor size range from 1-5 cm (65.7%) were the most common in each category.

Conclusion: Our findings indicate that diabetic RCC patients have a predominance of localized, small clear cell RCC. In addition, females with a history of RCC have a higher frequency of diabetes compared to males. This is the first report of clinical and histopathological features of RCC associated with diabetes.

Epidemiology of renal cell cancer

Renal cell cancer (RCC) is increasingly diagnosed at an early stage in many countries, which likely contributes to the recent leveling of RCC mortality in the United States and many European countries. However, over all stages nearly 50% of the patients die within 5 years after diagnosis. Smoking and obesity may account for approximately 40% of all incidental cases in high-risk countries. Besides obesity, rising prevalence of hypertension may play a growing role. Several other occupational and lifestyle factors may also affect the risk of RCC. Genetic variations may be an important factor in the differing incidence among populations.

The Ets transcription factor ELF5 functions as a tumor suppressor in the kidney

Renal cell carcinoma is an important clinical disease with poorly understood etiology. ELF5 is an epithelial-specific member of the Ets family of transcription factors, characterized by the 80 amino acid Ets domain that binds the purine-rich GGAA/T Ets motif found in the promoter regions of a variety of genes. Since ELF5 is highly expressed in kidney and has been postulated to function as a tumor suppressor, at least in the context of the breast, we investigated its role in kidney cancer. In renal cell carcinoma ELF5 expression was consistently decreased in tumor samples versus normal. ELF5 mRNA was decreased in 94% of lesions tested and ELF5 protein was undetectable in 40/40 kidney-derived carcinomas. Re-expression of the ELF5 gene in 786-O renal carcinoma cells suppressed their tumorigenic capacity in vitro and in vivo. This work is the first to suggest that ELF5 has tumor suppressor activity in the kidney.

Genome-wide association study of renal cell carcinoma identifies two susceptibility loci on 2p21 and 11q13.3

We conducted a two-stage genome-wide association study of renal cell carcinoma (RCC) in 3,772 affected individuals (cases) and 8,505 controls of European background from 11 studies and followed up 6 SNPs in 3 replication studies of 2,198 cases and 4,918 controls. Two loci on the regions of 2p21 and 11q13.3 were associated with RCC susceptibility below genome-wide significance. Two correlated variants (r² = 0.99 in controls), rs11894252 (P = 1.8 × 10⁻⁸) and rs7579899 (P = 2.3 × 10⁻⁹), map to EPAS1 on 2p21, which encodes hypoxia-inducible-factor-2 alpha, a transcription factor previously implicated in RCC. The second locus, rs7105934, at 11q13.3, contains no characterized genes (P = 7.8 × 10⁻¹⁴). In addition, we observed a promising association on 12q24.31 for rs4765623, which maps to SCARB1, the scavenger receptor class B, member 1 gene (P = 2.6 × 10⁻⁸). Our study reports previously unidentified genomic regions associated with RCC risk that may lead to new etiological insights.

Family history of cancer and renal cell cancer risk in Caucasians and African Americans

Background:

The association between renal cell carcinoma (RCC) risk and family history of cancer has not been examined with an adequate number of African Americans (AAs).

Methods:

In a population-based case–control study, unconditional logistic regression was used to calculate the association between RCC risk and a family history of cancer among 1217 RCC cases and 1235 controls.

Results:

Increased RCC risk was shown for subjects with at least one first-degree relative with kidney cancer (odds ratio=2.29; 95% confidence interval=1.31–4.00). No differences in risk were observed when analyses were stratified by race. For Caucasians, excess risk was observed among those reporting a sibling with kidney cancer, whereas for AAs, increased risk occurred among subjects reporting either a sibling or parent affected with the disease. A family history of non-renal cancers, and those related to smoking or to the von Hippel–Lindau syndrome, revealed no association with RCC risk.

Conclusion:

The RCC risk associated with a family history of kidney cancer is similar among Caucasians and AAs.

Diabetes and risk of incident cancer: a large population-based cohort study in Israel

Type 2 diabetes mellitus has been associated with an increased risk of a variety of cancers in observational studies, but few have reported the relationship between diabetes and cancer risk in men and women separately. The main goal of this retrospective cohort study was to evaluate the sex-specific risk of incident overall and site-specific cancer among people with DM compared with those without, who had no reported history of cancer at the start of the follow-up in January 2000. During an average of 8 years of follow-up (SD = 2.5), we documented 1,639 and 7,945 incident cases of cancer among 16,721 people with DM and 83,874 free of DM, respectively. In women, DM was associated with an adjusted hazard ratio of 1.96 (95% CI: 1.53-2.50) and 1.41 (95% CI: 1.20-1.66) for cancers of genital organs and digestive organs, respectively. A significantly reduced HR was observed for skin cancer (0.38; 95% CI: 0.22-0.66). In men with DM, there was no significant increase in overall risk of cancer. DM was related with a 47% reduction in the risk of prostate cancer. These findings suggest that the nature of the association between DM and cancer depends on sex and specific cancer site.

Variants in blood pressure genes and the risk of renal cell carcinoma

Hypertension is a known risk factor for renal cell carcinoma (RCC), although the underlying biological mechanisms of its action are unknown. To clarify the role of hypertension in RCC, we examined the risk of RCC in relation to 142 single-nucleotide polymorphisms (SNPs) in eight genes having a role in blood pressure control. We analyzed 777 incident and histologically confirmed RCC cases and 1035 controls who completed an in-person interview as part of a multi-center, hospital-based case-control study in Central Europe. Genotyping was conducted with an Illumina GoldenGate Oligo Pool All assay using germ line DNA. Of the eight genes examined, AGT (angiotensinogen) was most strongly associated with RCC (minimum P-value permutation test = 0.02). Of the 17 AGT tagging SNPs considered, associations were strongest for rs1326889 [odds ratio (OR) = 1.35, 95% confidence interval (CI) = 1.15-1.58] and rs2493137 (OR = 1.31, 95% CI = 1.12-1.54), which are located in the promoter. Stratified analysis revealed that the effects of the AGT SNPs were statistically significant in participants with hypertension or high body mass index (BMI) (> or =25 kg/m(2)), but not in subjects without hypertension and with a normal BMI (<25 kg/m(2)). Also, haplotypes with risk-conferring alleles of markers located in the promoter and intron 1 regions of AGT were significantly associated with RCC compared with the common haplotype in subjects with hypertension or high BMI (global P = 0.003). Our findings suggest that common genetic variants of AGT, particularly those in the promoter, increase RCC risk among subjects who are hypertensive or overweight.

Apolipoprotein E/C1 locus variants modify renal cell carcinoma risk

Lipid peroxidation is considered a unifying mechanistic pathway through which known risk factors induce renal cell carcinoma (RCC). We hypothesized that genes selected a priori for their role in lipid peroxidation would modify cancer risk. We genotyped 635 single nucleotide polymorphisms (SNP) in 38candidate genes in 777 Caucasian RCC cases and 1,035 controls enrolled in a large European case-control study. Top candidate SNPs were confirmed among 718 Caucasian cases and 615 controls in a second study in the United States. Two of the three SNPs (rs8106822 and rs405509) that replicated in the U.S. study were within a regulatory region of the APOE promoter. The OR for rs8106822 A>G variant was 1.22(AG) and 1.41(GG) (P(trend) = 0.01) in the European study, 1.05(AG) and 1.51(GG) (P(trend) = 0.03) in the U.S. study, and 1.15(AG) and 1.44(GG) (P(trend) = 0.001) among 1,485 cases and 1,639 controls combined. The rs405509 G>T variant was associated with risk in the European (OR, 0.87(TG); OR, 0.71(TT); P(trend) = 0.02), the U.S. (OR, 0.68(TG); OR, 0.71(TT); P(trend) = 0.02), and both studies combined (OR(TG), 0.79; OR(TT), 0.71; P(trend) = 0.001), as was the G-G haplotype (r(2) = 0.64; P= 4.7 x 10(-4)). This association is biologically plausible as SNP rs405509 was shown to modify protein binding and transcriptional activity of the APOE protein in vitro and is in linkage disequilibrium with key known variants defining the e2, e3, and e4 alleles that modify risk of atherosclerosis, Alzheimer's disease risk, and progression to AIDS. In two large case-control studies, our findings further define a functional region of interest at the APOE locus that increases RCC susceptibility.

Obesity and renal cell carcinoma: epidemiology, underlying mechanisms and management considerations

The incidence of both renal cell carcinoma (RCC) and obesity are steadily rising in Western societies. Recent studies have established that obesity is a significant risk factor for the development of several malignancies, including RCC. However, the mechanisms underlying this relationship remain to be fully elucidated. We review herein the epidemiological links between obesity and RCC, the potential mechanisms by which obesity can influence RCC development and progression, and the special considerations related to the treatment of obese patients with RCC.

Fish, vitamin D, and flavonoids in relation to renal cell cancer among smokers

Fish, vitamin D, flavonoids, and flavonoid-containing foods may have cardiovascular benefits and therefore may also reduce the risk of renal cell cancer. Risk was prospectively assessed in the Alpha-Tocopherol Beta-Carotene Cancer Prevention Study (1985-2002) cohort (N = 27,111; 15.2 mean person-years of follow-up). At enrollment, demographic, health, and dietary history information was recorded. Individuals who smoked less than 5 cigarettes/day, with chronic renal insufficiency or prior cancer, were excluded. Hazard ratios and 95% confidence intervals from Cox regression were used to compare upper quartiles (quartiles 2-4) with the lowest quartile (quartile 1) of dietary intake. Among 228 cases, risk (quartile 4 vs. quartile 1) was associated with consumption of the flavonoid quercetin (hazard ratio = 0.6, 95% confidence interval: 0.4, 0.9; P(trend) = 0.015) and Baltic herring (hazard ratio = 2.0, 95% confidence interval: 1.4, 3.0; P(trend) < 0.001), with adjustment for age, body mass index, smoking, blood pressure, alcohol use, physical activity, urban residence, and education. In geographically stratified models, the risks associated with herring and total fish intake appeared to be highest in the urban coast region, although the interaction was not statistically significant. These results suggest that the flavonoid quercetin may prevent renal cell cancer among male smokers. The possible risk associated with fish intake warrants further investigation before conclusions may be drawn.

Epidemiologic characteristics and risk factors for renal cell cancer

Incidence rates of renal cell cancer, which accounts for 85% of kidney cancers, have been rising in the United States and in most European countries for several decades. Family history is associated with a two- to four-fold increase in risk, but the major forms of inherited predisposition together account for less than 4% of renal cell cancers. Cigarette smoking, obesity, and hypertension are the most consistently established risk factors. Analgesics have not been convincingly linked with renal cell cancer risk. A reduced risk of renal cell cancer among statin users has been hypothesized but has not been adequately studied. A possible protective effect of fruit and vegetable consumption is the only moderately consistently reported dietary finding, and, with the exception of a positive association with parity, evidence for a role of hormonal or reproductive factors in the etiology of renal cell cancer in humans is limited. A recent hypothesis that moderate levels of alcohol consumption may be protective for renal cell cancer is not strongly supported by epidemiologic results, which are inconsistent with respect to the categories of alcohol consumption and the amount of alcohol intake reportedly associated with decreased risk. For occupational factors, the weight of the evidence does not provide consistent support for the hypotheses that renal cell cancer may be caused by asbestos, gasoline, or trichloroethylene exposure. The established determinants of renal cell cancer, cigarette smoking, obesity, and hypertension, account for less than half of these cancers. Novel epidemiologic approaches, including evaluation of gene–environment interactions and epigenetic mechanisms of inherited and acquired increased risk, are needed to explain the increasing incidence of renal cell cancer.

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

Malignant kidney tumors account for approximately 2% of all new primary cancer cases diagnosed in the United States, with an estimated 30,000 cases occurring annually. Although a variety of agents, chemical and biological, have been implicated as causal agents in the development of renal cell carcinoma (RCC), the etiology remains enigmatic. The strongest association has been developed between cigarette smoking and renal cancer however consistent, positive associations between RCC and obesity, diabetes, and hypertension have also been reported. In addition, more recent investigations of familial kidney cancer syndromes indicate that a strong genetic component contributes to RCC development. Several genes have been identified through investigation of familial kidney cancer syndromes. This review article describes recent trends in RCC incidence and the currently identifiable etiological causes that account for approximately half of the RCC cases diagnoses. The remainder of this review then focuses on additional risk factors that have thus far not been well examined but may be helpful in explaining the increasing incidence trends and the geographic or racial variation observed nationally and worldwide.

Family history and risk of renal cell carcinoma: results from a case-control study and systematic meta-analysis

We conducted a case-control analysis, a family-based population analysis, and a meta-analysis to assess the role of family history of cancer and kidney cancer in association with the risk of renal cell carcinoma (RCC). A total of 325 cases and 329 controls were identified from an ongoing case-control study of RCC. Study variables were assessed through 45-minute structured face-to-face interviews. In the case-control analysis, a family history of any cancer (in first-degree relatives) was associated with a nonsignificant 1.2-fold increase in RCC risk [95% confidence interval (95% CI), 0.8-1.6]. The risk increased to 1.7 and became significant when the relative was a sibling (95% CI, 1.1-2.5). A family history of kidney cancer (kidney cancer in first-degree relatives) was associated with a 4.3-fold significantly increased risk of RCC (95% CI, 1.6-11.9). The cases reported a total of 2,536 first-degree relatives of which 21 (0.8%) had kidney cancer, and the controls reported a total of 2,333 first-degree relatives of which 5 (0.2%) had kidney cancer (P=0.003). In the family-based population analysis, a family history of kidney cancer was associated with a 2.8-fold increased risk of RCC (95% CI, 1.0-7.8). The meta-analysis further confirmed this significant association with a 2.2-fold increased risk of RCC (95% CI, 1.6-2.9). To our knowledge, this is the first study to use three analytic strategies to investigate the association between a family history of kidney cancer and risk of RCC, and the first systematic evaluation of the relative risk for developing RCC associated with family history.

A compendium of familial relative risks of cancer among first degree relatives: a population-based study

Familial clustering of cancer is expected to occur at practically all anatomical sites. However, few studies have had sufficient size to investigate different sites simultaneously and with adjustment for confounders. We evaluated familial clustering in the Netherlands Cohort Study in which 120,852 men and women, aged 55-69 years in 1986 were followed up for 13.3 years. 14,025 Probands, 6,629 parents and 4,271 siblings were diagnosed with cancer. Relative Risks (RR) of cancer in first degree family members were calculated by using multivariable Cox regression analyses. We also calculated false-positive reporting probabilities. Significant concordant familial clustering was observed for stomach (RR(father) = 1.89, RR(parent) = 1.66, RR(sister) = 3.33, RR(sibling) = 2.38, RR(1st degree) = 1.69), colon/rectum (RR(father) = 1.82, RR(mother) = 1.83, RR(parent) = 1.88, RR(1st degree) = 1.56), lung (RR(brother) = 1.50) and breast cancer (RR(mother) = 1.65, RR(sister) = 1.72, RR(1st degree) = 1.72) with low false-positive reporting probabilities. Significant discordant familial clustering has been observed for combinations of pancreas-colon/rectum (RR(mother) = 2.42, RR(parent) = 1.89, RR(1st degree) = 1.73), larynx-lung (RR(father) = 3.35, RR(parent) = 2.84, RR(1st degree) = 2.30), lung-oesophagus (RR(sibling) = 3.49), breast-bladder (RR(father) = 2.79, RR(parent) = 2.61), endometrium-stomach (RR(mother) = 2.32), ovarium-oesophagus (RR(1stdegree) = 4.19), prostate-colon/rectum (RR(parent) = 1.46) and bladder-larynx/pharynx (RR(father) = 2.49) cancer, although false-positive reporting probabilities were higher for these associations. Familial clustering of cancer occurs at most sites but is generally modest. Some observed discordant familial clustering is surprising but should be interpreted with caution as their prior probability is low.

Renal cancer

In Europe, renal cancer (that is neoplasia of the kidney, renal pelvis or ureter (ICD-9 189 and ICD-10 C64-C66)) ranks as the seventh most common malignancy in men amongst whom there are 29,600 new cases each year (3.5% of all cancers). Tobacco, obesity and a diet poor in vegetables are all acknowledged risk factors, along with specific occupational and environmental factors. A familial history of renal carcinoma is also likely to increase the risk. Renal carcinoma may remain clinically occult for most of its course. The classic presentation of pain, haematuria, and flank mass occurs in only 9% of patients and is often indicative of advanced disease. Approximately 30% of patients with renal carcinoma present with metastatic disease, 25% with locally advanced renal carcinoma and 45% with localized disease. Metastases are typically found in the lung, soft tissue, bone, liver, cutaneous sites, and central nervous system. The most important staging technique is a computed tomography (CT) scan of the whole abdomen. Survival rates are more favourable for patients with tumours confined to the kidney. Five-year survival for patients with metastatic renal carcinoma is comprised between 0 and 20%. Radical nephrectomy is the standard intervention for renal cancer. Intrinsic resistance to chemotherapy has long been a hallmark of renal carcinoma. Limited options are available for the systemic therapy, and no chemotherapeutic regimen is accepted as a standard of care. Biologic agents represent the major effective therapies for widespread metastatic renal cancer. An antiangiogenic strategy, the neutralization of VEGF, can slow the growth rate of advanced cancer.

Family history of urogenital cancers in patients with bladder, renal cell and prostate cancers

Family history of urogenital cancers has been associated with an increased risk of cancer at the same sites. To evaluate the risks of bladder, prostate and renal cell neoplasms for family history of urogenital cancers in first-degree relatives, we analysed data from a case-control study conducted in northern Italy between 1985 and 1992 and including a total of 1,356 incident, histologically confirmed cancer cases: 727 bladder, 348 renal cell and 281 prostate cancer cases. Controls were 1,067 patients admitted to the same network of hospitals for acute, nonneoplastic conditions. Unconditional logistic regression was used to estimate odds ratios (ORs) of urogenital cancers, adjusting for age, sex, study centre, education, body mass index, smoking habit, alcohol consumption and number of brothers and, where appropriate, sisters. ORs of urogenital cancers for subjects with at least 1 first-degree relative with cancer at the same site were 6.1 [95% confidence interval (CI), 2.3-16.6] for bladder, 2.0 (95% CI: 0.6-6.2) for renal cell and 2.0 (95% CI: 0.9-4.1) for prostate cancer.

Family history and the risk of kidney cancer: a multicenter case-control study in Central Europe

An elevated familial relative risk may indicate either an important genetic component in etiology or shared environmental exposures within the family. Incidence rates of kidney cancer are particularly high in Central Europe, although no data were available on the familial aggregation or genetic background of kidney cancer in this region. We have, therefore, investigated the role of family history in first-degree relatives in a large multicenter case-control study in Central Europe. A total number of 1,097 cases of kidney cancer and 1,555 controls were recruited from 2000 to 2003 from seven centers in Czech Republic, Poland, Romania, and Russia. The risk of kidney cancer increased with the increasing number of relatives with history of any cancer [odds ratio (OR), 1.15; 95% confidence interval (95% CI), 1.00-1.31 per affected relative], and this association seemed to be more prominent among subjects with young onset (OR, 1.55; 95% CI, 1.09-2.20 per affected relative). Overall, the OR was 1.40 (95% CI, 0.71- 2.76) for the subjects who had at least one first-degree relative with kidney cancer after adjusting for tobacco smoking, body mass index, and medical history of hypertension, and this association was most apparent among subjects with affected siblings (OR, 4.09; 95% CI, 1.09-15.4). Based on the relative risk to siblings in our study population, we estimated that 80% of the kidney cancer cases are likely to occur in 20% of the population with the highest genetic risk, which indicate the importance of further investigation of genetic factors in cancer prevention for kidney cancer.

Family history of cancer and the risk of renal cell cancer

Only scant information is available on the association between family history of kidney cancer and risk of renal cell cancer (RCC), particularly as concerns the variation of the risk according to sex, age, and type of relative or the association of family history of other cancers with RCC. We thus investigated the issue using data from a large multicentric case-control study conducted in Italy between 1992 and 2004 on 767 patients (494 men and 273 women) under age 80 years, with incident, histologically confirmed RCC, and 1,534 controls under age 80 years, admitted to hospital for a wide spectrum of acute, nonneoplastic conditions and frequency matched 2:1 to cases by center, sex, and age. Conditional logistic regression models, conditioned on center, sex, and age and adjusted for year of interview, smoking, body mass index, and number of brothers and sisters were used to estimate odds ratios (OR). Eighteen RCC and 8 controls reported a family history of kidney cancer in one first-degree relative [OR, 5.2; 95% confidence interval (95% CI), 2.2-12.2]. No significant heterogeneity emerged according to sex or age of the proband or of the affected relative, or smoking habits, body mass index, and history of hypertension of the proband. Although not significant, the OR was higher when the affected relative was a sibling (OR, 7.0; 95% CI, 1.8-27.7) rather than a parent or child (OR, 4.3; 95% CI, 1.5-12.9), as suggested from previous studies. The OR of RCC was also significantly elevated for a family history of prostate cancer (OR, 1.9), leukemias (OR, 2.2), or any cancer (OR, 1.5).

Imaging of kidney cancer

Advances in molecular genetics have expanded the understanding of renal cell tumors. Now it is understood that renal cortical tumors are a family of neoplasms with distinct cytogenetics and molecular defects, unique histopathologic features, and different malignant potentials. Imaging contributes to clinical management of patients with renal tumors in providing diagnostic information for tumor detection, characterization, staging, treatment planning, and follow-up.

History of treated hypertension and diabetes mellitus and risk of renal cell cancer

BACKGROUND

An increased risk of renal cell cancer (RCC) has been reported in subjects with hypertension. Whether this association may vary according to sex, smoking, obesity, or RCC clinical presentation is unclear. Results on the link between diabetes mellitus and RCC are inconclusive.

PATIENTS AND METHODS

We conducted an Italian multicenter case-control study, including 767 (494 men, 273 women) incident cases of RCC, under 80 years of age, and 1534 hospital controls, frequency-matched to cases. Multiple logistic regression models, conditioned to center, sex, and age, and adjusted for period of interview, education, smoking, and body mass were used to estimate odds ratios (OR).

RESULTS

Compared with subjects never treated, patients with a history of treated hypertension [OR = 1.7, 95% confidence interval (CI) 1.4-2.1] reported an excess risk of RCC. This pattern was confirmed in different strata of sex, education, smoking habits, body mass, tumor histological type, stage, or grade. The attributable risk of RCC for treated hypertension in this population was 16%. A slight, nonsignificant increased risk was found for history of diabetes mellitus (OR = 1.3, 95% CI 0.9-1.7).

CONCLUSION

A possible causal role of hypertension in renal cell carcinogenesis is supported by the consistency of the direct association.

Body size and risk of renal cell carcinoma in the European Prospective Investigation into Cancer and Nutrition (EPIC)

Previous studies suggest that obesity is related to increased risk of renal cell carcinoma (RCC); however, only a few studies report on measures of central vs. peripheral adiposity. We examined the association between anthropometric measures, including waist and hip circumference and RCC risk among 348,550 men and women free of cancer at baseline from 8 countries of the European Prospective Investigation into Cancer and Nutrition (EPIC). During 6.0 years of follow-up we identified 287 incident cases of RCC. Relative risks were calculated using Cox regression, stratified by age and study center and adjusted for smoking status, education, alcohol consumption, physical activity, menopausal status, and hormone replacement therapy use. Among women, an increased risk of RCC was conferred by body weight (relative risk [RR] in highest vs. lowest quintile = 2.13; 95% confidence interval [CI] = 1.16-3.90; p-trend = 0.003), body mass index (BMI) (RR = 2.25; 95% CI = 1.14-4.44; p-trend = 0.009), and waist (RR = 1.67; 95% CI = 0.94-2.98; p-trend = 0.003) and hip circumference (RR = 2.30; 95% CI = 1.22-4.34; p-trend = 0.01); however, waist and hip circumference were no longer significant after controlling for body weight. Among men, hip circumference (RR = 0.44; 95% CI = 0.20-0.98; p-trend = 0.03) was related significantly to decreased RCC risk only after accounting for body weight. Height was not related significantly to RCC risk. Our findings suggest that obesity is related to increased risk of RCC irrespective of fat distribution among women, whereas low hip circumference is related to increased RCC risk among men. Our data give further credence to public health efforts aiming to reduce the prevalence of obesity to prevent RCC, in addition to other chronic diseases.

The value of risk-factor ("black-box") epidemiology

Risk-factor epidemiology has been denigrated by some as an empty search for associations, unguided by underlying theory. It has been defended for occasionally identifying useful (if poorly understood) potential interventions. We further defend risk-factor epidemiology as a valuable source of seemingly unrelated facts that await coherent explanation by novel theories and that provide empiric tests of theories. We illustrate these points with a theory that invokes lipid peroxidation as an explanation of an apparently incoherent accumulation of facts about renal-cell carcinoma. The example illustrates the value of viewing epidemiologic, laboratory, and clinical observations as a body of facts demanding explanation by proposed causal theories, whether or not those observations were collected with any hypothesis in mind.

Risk factors for adult renal cell carcinoma

This study confirmed several independent risk and protective factors for RCC identified in the authors' previous study. Protective factors such as oral contraceptive use and moderate alcohol consumption were identified only in women. Tobacco consumption and severe obesity were the main independent risk factors. There were other modifiable risk markers, however, such as occupational exposure, thiazidic drug intake, and urinary tract infections. The associations between risk factors and RCC were weak, even for tobacco, for which the association was weaker than that for lung cancer. The identified risks involve a large proportion of the population, however, and the risk attributable to these types of exposure is high. The authors' recommendations for the prevention of RCC are therefore similar to those for the prevention of cardiovascular disease and cancer, and should be disseminated to the general population. The high-risk groups identified are too large for a specific early-screening program for RCC, but such screening might be appropriate if restricted to selected age groups.

Diabetes mellitus as a predictor of cancer mortality in a large cohort of US adults

Several studies have suggested that diabetes mellitus may alter the risk of developing a variety of cancers, and the associations are biologically plausible. To learn more about the relation between diabetes and cancer mortality, the authors examined associations with selected cancers in a large, prospective US cohort of 467,922 men and 588,321 women who had no reported history of cancer at enrollment in 1982. After 16 years of mortality follow-up, diabetes was significantly associated with fatal colon cancer in men (multivariate relative risk (RR) = 1.20, 95% confidence interval (CI): 1.06, 1.37) and women (RR = 1.24, 95% CI: 1.07, 1.43) and with pancreatic cancer in men (RR = 1.48, 95% CI: 1.27, 1.73) and women (RR = 1.44, 95% CI: 1.21, 1.72). For men, diabetes was significantly associated with liver cancer (RR = 2.19, 95% CI: 1.76, 2.72) and bladder cancer (RR = 1.43, 95% CI: 1.14, 1.80). In addition, diabetes was significantly associated with breast cancer in women (RR = 1.27, 95% CI: 1.11, 1.45). These associations were not explained by high body mass. Our findings suggest that diabetes is an independent predictor of mortality from cancer of the colon, pancreas, female breast, and, in men, of the liver and bladder.

Does overweight impact on the prognosis of patients with renal cell carcinoma? A single center experience of 683 patients

BACKGROUND AND OBJECTIVES

An increased incidence of renal cell carcinoma (RCC) in obese patients has been reported by several authors. We investigated the association of body mass index (BMI) with prognosis of patients with RCC.

METHODS

From January 1994 to December 2000, 693 operations for RCC in 683 consecutive patients were performed at our institution. Patients' BMI at operation was evaluated, overall, tumor-specific and progression-free survival was investigated using the Kaplan-Meier method, for multivariate analysis the Cox regression model was used.

RESULTS

Four hundred seventeen patients were males, 266 females. Mean age was 62 years (range 16-88). BMI was available in 609 (89.2%). 371/609 (60.9%) of patients exhibited a BMI greater than 25. After a mean follow-up of 41.5 months, 86 (12.6%) patients died from metastatic RCC, and 29 (4.3%) were alive with metastatic disease. A significant advantage regarding overall (P = 0.015) and progression-free (0.017) but not tumor-specific survival (P = 0.057) was found for patients with a BMI of more than 25 compared to normal-weight patients. In multivariate analysis, BMI showed no significant association with tumor-specific survival.

CONCLUSIONS

Patients with a BMI of more than 25 had a better outcome compared to patients with normal weight in univariate analysis but not multivariate analysis.