Hypertension, obesity and their medications in relation to renal cell carcinoma

Effect of smoking, hypertension and lifestyle factors on kidney cancer - perspectives for prevention and screening programmes

Renal cell carcinoma (RCC) incidence has doubled over the past few decades. However, death rates have remained stable as the number of incidental renal mass diagnoses peaked. RCC has been recognized as a European health care issue, but to date, no screening programmes have been introduced. Well-known modifiable risk factors for RCC are smoking, obesity and hypertension. A direct association between cigarette consumption and increased RCC incidence and RCC-related death has been reported, but the underlying mechanistic pathways for this association are still unclear. Obesity is associated with an increased risk of RCC, but interestingly, improved survival outcomes have been reported in obese patients, a phenomenon known as the obesity paradox. Data on the association between other modifiable risk factors such as diet, dyslipidaemia and physical activity with RCC incidence are conflicting, and potential mechanisms underlying these associations remain to be elucidated.

Antihypertensive Drugs and Cancer Risk

Hypertension is the most prevalent comorbidity in cancer patients. Consequently, many cancer patients are prescribed antihypertensive drugs before cancer diagnosis or during cancer treatment. However, whether antihypertensive drugs affect the incidence, treatment efficacy, or prognosis of cancer remains unanswered. For instance, renin-angiotensin and β-adrenergic signaling may be involved not only in blood pressure elevation but also in cell proliferation, angiogenesis, and tissue invasion. Therefore, the inhibition of these pathways may have beneficial effects on cancer prevention or treatment. In this article, we reviewed several studies regarding antihypertensive drugs and cancer. In particular, we focused on the results of clinical trials to evaluate whether the use of antihypertensive drugs affects future cancer risk and prognosis. Unfortunately, the results are somewhat inconsistent, and evidence demonstrating the effect of antihypertensive drugs remains limited. We indicate that the heterogeneity in the study designs makes it difficult to clarify the causal relationship between antihypertensive drugs and cancer. We also propose that additional experimental studies, including research with induced pluripotent cells derived from cancer patients, single-cell analyses of cancer cell clusters, and clinical studies using artificial intelligence electronic health record systems, might be helpful to reveal the precise association between antihypertensive drugs and cancer risk.

AXL targeting by a specific small molecule or monoclonal antibody inhibits renal cell carcinoma progression in an orthotopic mice model

AXL tyrosine kinase activation enhances cancer cell survival, migration, invasiveness, and promotes drug resistance. AXL overexpression is typically detected in a high percentage of renal cell carcinomas (RCCs) and is strongly associated with poor prognosis. Therefore, AXL inhibition represents an attractive treatment option in these cancers. In this preclinical study, we investigated the antitumor role of a highly selective small molecule AXL inhibitor bemcentinib (BGB324, BerGenBio), and a newly developed humanized anti-AXL monoclonal function blocking antibody tilvestamab, (BGB149, BerGenBio), in vitro and an orthotopic RCC mice model. The 786-0-Luc human RCC cells showed high AXL expression. Both bemcentinib and tilvestamab significantly inhibited AXL activation induced by Gas6 stimulation in vitro. Furthermore, tilvestamab inhibited the downstream AKT phosphorylation in these cells. The 786-0-Luc human RCC cells generated tumors with high Ki67 and vimentin expression upon orthotopic implantation in athymic BALB/c nude mice. Most importantly, both bemcentinib and tilvestamab inhibited the progression of tumors induced by the orthotopically implanted 786-0 RCC cells. Remarkably, their in vivo antitumor effectiveness was not significantly enhanced by concomitant administration of a multi-target tyrosine kinase inhibitor. Bemcentinib and tilvestamab qualify as compounds of potentially high clinical interest in AXL overexpressing RCC.

Antihypertensive drugs and the risk of cancer: a critical review of available evidence and perspective

: The issue of a potential danger of antihypertensive drugs related to cancer susceptibility is currently generating a major debate in the scientific community, concerns in the public and emphasized interest from the media. The present article is a thorough review of what is known on the various classes of antihypertensive drugs concerning the risk of developing different neoplasms and about the suggested pathophysiological mechanisms, whenever available. The main limitations of evidence derived from studies currently available in this setting are also discussed, high-lightening the need for newly developed approaches to generate more accurate recommendations and informed advice for physicians.

Ulmus parvifolia Jacq. Exhibits Antiobesity Properties and Potentially Induces Browning of White Adipose Tissue

The bark of Ulmus parvifolia Jacq. (UP) was traditionally used as a diuretic and to treat intestinal inflammation. With modern evidence of the correlation of diuretics, gut inflammation, and obesity, our study has shown the antiobesity effects of the bark of UP. UP treatment reduced lipid production and adipogenic genes in vitro. In vivo studies revealed that UP 100 mg/kg and UP 300 mg/kg treatment significantly reduced mouse weight without reducing food intake, indicating increased energy expenditure. UP significantly reduced the weight of epididymal and subcutaneous adipose tissue and decreased liver weight. Histological analysis revealed improvement in the progression of nonalcoholic fatty liver disease and epididymal white adipose tissue hypertrophy induced by a HFD. Real-Time PCR of epididymal adipose tissue revealed significant increases of uncoupling protein-1 (UCP-1) and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) expression after UP 300 mg/kg treatments. Phosphorylation of AMP-activated protein α (AMPKα) was increased, while phosphorylation of Acetyl-CoA Carboxylase (ACC) was reduced. Our findings reveal the ability of UP to reduce the occurrence of obesity through increased browning of white adipose tissue via increased AMPKα, PPARγ, PGC-1α, and UCP-1 expression.

Risk of Renal Cell Carcinoma Associated with Calcium Channel Blockers: A Nationwide Observational Study Focusing on Confounding by Indication

BACKGROUND

We examined whether the apparent association between renal cell carcinoma (RCC) and use of dihydropyridine calcium channel blockers (CCBs) was explained by confounding by indication since hypertension, the main indication for CCBs, is a risk factor for RCC.

METHODS

Using Danish health registries, we conducted a nested case-control study including 7315 RCC cases during 2000-2015. We matched each case with up to 20 controls on age and sex using risk-set sampling. We estimated odds ratios (ORs) for long-term CCB use associated with RCC using conditional logistic regression. We addressed confounding by indication by (1) adjusting for hypertension severity indicators; (2) evaluating dose-response patterns; (3) examining whether other first-line anti-hypertensives were associated with RCC; and (4) using an active comparator new user design by nesting the study in new users of CCBs or angiotensin-converting enzyme inhibitors (ACEIs).

RESULTS

The adjusted OR for RCC associated with long-term CCB use compared to non-use was 1.76 (1.63-1.90). After we additionally adjusted for hypertension severity indicators, the OR remained elevated (OR 1.37; confidence interval [CI] 1.25, 1.49) with evidence of a dose-response pattern. Other anti-hypertensives were also associated with RCC, for example, ACEIs (OR 1.27; 95% CI = 1.16, 1.39) and thiazides (OR 1.22; 95% CI = 1.12, 1.34). In the active comparator new user design, the OR was 1.21 (95% CI = 0.95, 1.53) for use of CCBs compared with ACEIs.

CONCLUSIONS

In this population, confounding by indication appeared to explain at least part of the association between RCC and dihydropyridine CCBs.

Recent Warnings about Antihypertensive Drugs and Cancer Risk: Where Do They Come From?

The recent decrease in mortality related to cardiovascular diseases has largely been due to the more effective treatment of cardiovascular risk factors and secondary prevention therapies. More people than ever are now on long-term medications. Hypertension, which is one of the most common cardiovascular risk factors, requires life-long treatment. Recent evidence has focused attention on the risk of cancer that may be associated with the long-term use of antihypertensive therapy. This article summarises available evidence surrounding three recent events in this setting. Even though this is a crucial patient safety issue, there are no conclusive answers at this time and further studies are required.

Early life body size in relation to risk of renal cell carcinoma in adulthood: a Danish observational cohort study

Adult obesity increases risks of renal cell carcinoma (RCC). This study investigated if birth weight, child body mass index (BMI) and height are associated with adult RCC. The study included 301,418 children (152,569 boys) from the Copenhagen School Health Records Register born 1930-1985 with measured weights and heights at ages 7 to 13 years. Birth weight was obtained by parental report. BMI and height were transformed to z-scores, and BMI was categorized as normal BMI or overweight. RCC was identified by linkage to the Danish Cancer Registry. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated by Cox proportional hazards regression. During follow-up, 1010 individuals (680 men) were diagnosed with RCC. BMI and height were positively associated with RCC with no significant sex-differences (age 13: HR = 1.14, 95% CI 1.06-1.23 per BMI z-score, HR = 1.12, 95% CI 1.05-1.20 per height z-score). Compared to children with normal BMI at ages 7 and 13 years, children with overweight only at age 13 had higher risks of RCC (HR = 1.67, 95% CI 1.24-2.26). Compared to children with average growth in height, persistently taller-than-average children (HR = 1.06, 95% CI 1.03-1.10) and children who changed from average to above-average height (HR = 1.08, 95% CI 1.01-1.15) had increased risks of RCC. Birth weight was positively associated with RCC (HR = 1.12, 95% CI 1.05-1.20 per 500 grams). Birth weight, childhood BMI and height were positively associated with RCC risk in men and women.

Antihypertensive medications are associated with the risk of kidney and bladder cancer: a systematic review and meta-analysis

Several studies have indicated that the use of antihypertensive medications may influence the incidence of bladder/kidney cancer, with some scholars refuting any such association. Hence, a systematic review is needed to verify this linkage. we comprehensively searched PubMed, Embase, Web of Science, and the Cochrane Library for original studies reporting a relationship between antihypertensive medications and risk of bladder/kidney cancer. We included 31 articles comprising 3,352,264 participants. We found a significant association between the risk of kidney cancer and any antihypertensive medications use (relative risk (RR) = 1.45, 95% CI 1.20-1.75), as well as angiotensin-converting enzyme inhibitors (RR = 1.24, 95% CI 1.04-1.48), angiotensin II receptor blockers (ARB) (RR = 1.29, 95% CI:1.22-1.37), beta-blockers (RR = 1.36, 95% CI 1.11-1.66), calcium-channel blockers (RR = 1.65, 95% CI 1.54-1.78) and diuretics (RR = 1.34, 95% CI 1.19-1.51). In case of bladder cancer, a statistical significance was observed with the use of ARB (RR = 1.07, 95% CI 1.03-1.11) but not with the other antihypertensive medications. There was a linear association between the duration of antihypertensive medications and the risk of kidney cancer (P = 0.061 for a non-linear trend) and the pooled RR for the per year increase in antihypertensive medications duration of use was 1.02 (95% CI: 1.01-1.02). Our results indicate that there is a significant association between each class of antihypertensive medications and the risk of kidney cancer, and this trend presented as a positive linear association. Furthermore, the use of ARB has been linked to the risk of bladder cancer.

Association between blood pressure and risk of cancer development: a systematic review and meta-analysis of observational studies

With the exception of renal cell carcinoma, studies assessing the association between hypertension and other cancers are inconsistent. We conducted a meta-analysis to assess this evidence. We included observational studies investigating the association between any definition of hypertension or systolic and diastolic blood pressure and risk of any cancer, after searching PubMed until November 2017. We calculated summary relative risks (RR) and 95% confidence intervals (CI) using inverse-variance weighted random effects methods. A total of 148 eligible publications were identified out of 39,891 initially screened citations. Considering only evidence from 85 prospective studies, positive associations were observed between hypertension and kidney, colorectal and breast cancer. Positive associations between hypertension and risk of oesophageal adenocarcinoma and squamous cell carcinoma, liver and endometrial cancer were also observed, but the majority of studies did not perform comprehensive multivariable adjustments. Systolic and diastolic blood pressure were positively associated with risk of kidney cancer but not with other cancers. In addition to the previously well-described association between hypertension and risk of kidney cancer, the current meta-analysis suggested that hypertensive individuals may also be at higher risk of colorectal and breast cancer. However, careful interpretation is required as most meta-analyses included relatively small number of studies, several relative risks had weak or moderate magnitude and maybe affected by residual confounding.

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.

Bisphosphonate use and risk of renal cell carcinoma: A population-based case-control study

The purpose of this study was to evaluate the association between the use of bisphosphonates and the risk of developing renal cell carcinoma (RCC). We conducted a case-control study in Denmark, using data linked from population-based health and administrative registries. We identified all cases of RCC from 1996 to 2013 and sampled population controls in a 10:1 ratio from the underlying population free of RCC, while matching on sex, birth year and calendar time. Bisphosphonate use before RCC diagnosis, excluding the year leading up to the diagnosis, was measured using outpatient prescription dispensations. We used conditional logistic regression to compute crude and adjusted odds ratios (ORs) comparing ever vs. never bisphosphonate use in doses indicated for treatment of osteoporosis, overall and stratified by sex, with the OR estimating the incidence rate ratio. We also examined the effects by cumulative dose and specific agent. There were 2748 RCC cases and 27 480 controls. The adjusted ORs for ever vs never bisphosphonate use were 1.07 (95% confidence interval: 0.94-1.22) overall; 1.15 (1.00-1.32) for women; and 0.78 (0.54-1.12) for men. Smoking could not be directly controlled for in the analysis. We found a weak association between use of oral bisphosphonates and risk of renal cell carcinoma in females. The observed association could be due to confounding by cigarette smoking, and future studies are required to assess this association further.

Modifiable risk factors to reduce renal cell carcinoma incidence: Insight from the PLCO trial

INTRODUCTION

Identify modifiable factors contributing to renal cell carcinoma in the PCLO to target disease prevention and reduce health care costs.

METHODS

The prostate, lung, colorectal, and ovarian database were queried for the primary outcome of kidney cancer. Demographics were investigated, specifically focusing on modifiable risk factors. Statistical analysis includes the Student t-test for continuous variables, chi-squared or Fisher's exact tests for dichotomous and categorical variables for bivariate analysis. The Cox proportional hazards model was used in a multivariate time-to-event analysis.

RESULTS

We investigate existing data relating specifically to renal cancer. After missing data were excluded, we analyzed 149,683 subjects enrolled in the prostate, lung, colorectal, and ovarian trial and noted 0.5% (n = 748) subjects developed renal cancer. Age, male gender, body mass index, diabetes, and hypertension were all significant associated with renal cancer in bivariate analysis (P<0.05). Men have a significant increased risk of kidney cancer over women (hazard ratio [HR] = 1.85; 95% CI: 1.58-2.16; P<0.0001). Nonmodifiable risk factors that are associated with kidney cancer include age (HR = 1.05; 95% CI: 1.01; 1.05, P = 0.001). Modifiable risk factors include obesity measured by body mass index (HR = 1.05; 95% CI: 1.02-1.07; P<0.0001), hypertension (HR = 1.32; 95% CI: 1.13-1.54; P = 0.0004), and smoking in pack-years (HR = 1.04; 95% CI: 1.02-1.07; P = 0.0002).

CONCLUSIONS

Obesity, hypertension, and smoking are the 3 modifiable risk factors that could aggressively be targeted to reduce renal cell carcinoma.

Spironolactone use and risk of incident cancers: a retrospective, matched cohort study

AIMS

Spironolactone is widely used to treat heart failure, hypertension and liver disease with increased usage in recent years. Spironolactone has endocrine effects that could influence cancer risks and historical reports suggest possible links with increased risk of certain types of cancer. The aim of this study was to assess the effect of spironolactone exposure on cancer incidence.

METHODS

A pharmacoepidemiological propensity score-matched cohort study was performed to assess the effect of spironolactone exposure on cancer incidence. Cox proportional hazards models were used to analyse time to first diagnosis of each prespecified cancer and hazard ratios for spironolactone exposure are presented. The setting for the study was UK primary care using the Clinical Practice Research Datalink. The participants were 74 272 patients exposed to spironolactone between 1986 and 2013, matched 1:2 with unexposed controls. The prespecified primary outcomes were the first incidence of ovarian, endometrial, pancreatic, colorectal, prostate, renal cell, pharyngeal and thyroid cancers, and myelomonoblastic/-cytic leukaemias. Secondary outcomes were the remaining 27 types of cancer.

RESULTS

There was no evidence of an increased risk of any cancer associated with spironolactone use. Spironolactone use was associated with a significantly lower risk of prostate cancer (hazard ratio 0.69; 95% confidence interval 0.60-0.80, P < 0.001).

CONCLUSIONS

In this study, spironolactone use was associated with a lower incidence of prostate cancer, the most common cancer in men in the UK. The possible mechanisms and clinical implications merit further investigation.

Antihypertensive medication use and risk of renal cell carcinoma

PURPOSE

Use of antihypertensive medications has been associated with renal cell carcinoma (RCC), but it is unclear whether specific types of medications increase RCC risk independent of the effect of hypertension, or whether the association varies by histologic subtype. To address this question, we analyzed data from a U.S. population-based case-control study of RCC.

METHODS

We collected information on participants' use of drugs to treat hypertension, heart problems, weight control, and swelling. We computed odds ratios (ORs) and 95% confidence intervals (CIs) for each of four major drug classes, separately for participants with (643 cases, 443 controls) and without (500 cases, 718 controls) a history of hypertension, using unconditional logistic and polytomous regression models.

RESULTS

None of the antihypertensive drug types was associated with RCC overall. Among participants with a history of hypertension, papillary RCC was associated with long-term use of diuretics (OR = 3.1, 95% CI = 1.4-6.7 for 16+ years, 16 cases, 31 controls; P-trend = 0.014) and calcium channel blockers (OR = 2.8, 95% CI = 1.1-7.4 for 16+ years, 8 cases, 14 controls; P-trend = 0.18), while corresponding ORs for clear cell RCC were weaker (ORs 0.9 and 1.5, respectively) and nonsignificant. The only significant finding among those with no hypertension history was an association between calcium channel blockers and papillary RCC (OR = 17.9, 95% CI = 5.9-54.5) that was based on small numbers (8 cases, 9 controls). There was little evidence of an association between RCC and use of ACE inhibitors or beta blockers.

CONCLUSIONS

Our study, while inconclusive for overall RCC, provides, to our knowledge, the first evidence supporting an association between antihypertensive medications and papillary RCC. These subtype-specific findings, although based on small numbers, warrant further investigation.

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.

Association of hypertension and obesity with renal cell carcinoma risk: a report from the Shanghai Men's and Women's Health Studies

PURPOSE

Consistently reported associations between hypertension and obesity and renal cell carcinoma (RCC) risk have largely come from studies in Western populations. These associations were examined in a case-control study nested in the Shanghai Women's Health Study (SWHS, 1996-2000) and Shanghai Men's Health Study (SMHS, 2001-2006).

METHODS

Overall, 271 incident RCC cases (124 women, 147 men) were identified through 31 December 2011, and 2,693 controls were individually matched by sex, age, and calendar time at cohort enrollment, and menopausal status (for women). Participants completed a structured questionnaire by in-person interview at baseline, and conditional logistic regression was used to estimate odds ratios (ORs) and 95 % confidence intervals (CIs).

RESULTS

Self-reported hypertension was associated with a significant 40 % increased risk of RCC among women and men (95 % CI 1.1, 1.9). Body mass index (BMI), modeled continuously, was associated with an elevated risk of RCC among men, with an OR of 1.5 (95 % CI 1.1, 2.0) per 5 kg/m(2) increase in BMI, but not among women.

CONCLUSIONS

Hypertension is independently associated with risk of RCC among both women and men in Shanghai, while overweight and obesity appear to be associated with risk of RCC in Chinese men only.

The impact of nutrition in urogenital cancers

Prostate, bladder and kidney cancers remain the most common cancers of the urinary tract. Despite improved primary prevention, detection and treatment, the incidence of age-related cancers of the urinary tract is likely to rise as a result of global population ageing. An association of diet with prostate, bladder and kidney carcinogenesis is plausible since the majority of metabolites, including carcinogens, are excreted through the urinary tract. Moreover, large regional differences in incidence rates of urologic tumours exist throughout the world. These rates change when people relocate to different geographic areas, which is suggestive of a strong environmental influence. As a result of these observations, numerous studies have been conducted to assess the effects of diet and nutritional status in kidney, bladder and prostate carcinogenesis. Here, we review the literature assessing the effect of diet and nutritional status on urological cancer risk, which has attracted the most interest.

Cigarette smoking and other risk factors for kidney cancer death in a Japanese population: Japan Collaborative Cohort Study for evaluation of cancer risk (JACC study)

BACKGROUND

Cigarette smoking is the largest single recognized cause of human cancers. In Western countries, many epidemiologists have reported risk factors for kidney cancer including smoking. However, little is known about the Japanese population.

MATERIALS AND METHODS

We evaluated the association of smoking with the risk of kidney cancer death in the Japan Collaborative Cohort (JACC) Study. Participants included 46,395 males and 64,190 females. The Cox proportional hazards model was used to determine age-and-sex adjusted relative risks.

RESULTS

A total of 62 males and 26 females died from kidney cancer during the follow-up of 707,136 and 1,025,703 person-years, respectively. Heavy smokers (Brinkman index >1200), fondness of fatty foods, hypertension, diabetes mellitus (DM), and obesity were suggested to increase the risk of renal cell carcinoma while walking was suggested to decrease the risk. Even after controlling for age, sex, alcohol drinking and DM, heavy smoking significantly increased the risk.

CONCLUSIONS

The present study suggests that six factors including smoking may increase and/or reduce the risk of kidney cancer in the Japanese population. Because of the small number of outcomes, however, we did not evaluate these factors after adjusting for all possible confounding factors. Further studies may be needed to confirm the findings in this study.

Urological complications of illicit drug use

Illicit drug use is prevalent worldwide; over 24 million people are estimated to have used recreational drugs during the past month in the UK and USA alone. Illicit drug use can result in a wide spectrum of potential medical complications that include many urological manifestations. To ensure optimal care and treatment, urologists need to be cognizant of these complications in their patients, particularly among youths. Ketamine uropathy is thought to affect over one-quarter of ketamine users and can lead to severe lower urinary tract symptoms, as well as upper tract obstruction. Cannabis use has been associated with an increased risk of bladder cancer, prostate cancer and nonseminomatous germ cell tumours in case-control studies. Fournier's gangrene has been reported following injection of heroin and cocaine into the penis. Excessive use of cough medicines can lead to the development of radiolucent stones composed of ephedrine, pseudoephedrine and guaifenesin. As the current evidence is mostly limited to case reports and case series, future epidemiological studies are needed to fully address this issue.

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.:

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.

Risk of neoplasms in acromegaly

Acromegaly is a chronic disease caused by the excessive secretion of growth hormone (GH), and as a result, of insulin-like growth factor-1 (IGF-1). Untreated, the condition reduces the patients' life expectancy and leads to a series of complications, among which an increased risk of carcinogenesis is considered most important. This paper is an analysis of the publications on the issue of the formation of neoplasms, both malignant and benign, in acromegalic patients. Although the influence of acromegaly on carcinogenesis remains controversial, a number of studies indicate that the frequency of developing tumors in this patient group is higher. Moreover, numerous publications particularly stress the increased risk of developing neoplasms in patients who had been untreated for a long period of time and show elevated levels of GH and IGF-1. Consequently, a quick diagnosis and the implementation of effective treatment play a key role in the management of this disease.

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.

Impact of glutathione transferase M1, T1, and P1 gene polymorphisms in the genetic susceptibility of North Indian population to renal cell carcinoma

In this study, we investigated the association of GSTP1, GSTM1, and GSTP1 genetic variants with renal cell carcinoma (RCC) among North Indian patients. The difference in frequency of the GSTT1 null genotype between cases and control subjects was statistically significant (active ver. null, odds ratio [OR]=0.368; confidence intervals [CI] 95%=0.243-0.557, p=0.001). The differences in the frequency of GSTP1 genotypes were statistically significant (AA ver. AG/GG, OR=1.879; CI 95%=0.355-0.797, p=0.002). Higher allelic frequency of the GSTP1 G allele was associated with RCC cases (G ver. A allele, OR=1.534; 95% CI=1.159-2.030, p=0.003). The gene-gene interaction in terms of three-way combination of GSTM1 null, GSTT1 null, and GSTP1 (AG/GG) resulted in 4.5-fold increase in RCC risk (OR=4.452; 95% CI=2.220-9.294). Similarly, our study revealed that GST polymorphism might be a vital determinant of advancement to higher pathological stages and histological grades of RCC. Our findings suggest that genetic variability in members of the GST gene family may be associated with an increased susceptibility to RCC and its progression.

Hypertension and risk of renal cell carcinoma among white and black Americans

BACKGROUND

Renal cell carcinoma and hypertension (a well-established renal cancer risk factor) are both more frequent among blacks than whites in the United States. The association between hypertension and renal cell carcinoma has not been examined in black Americans. We investigated the hypertension-renal cancer association by race, and we assessed the role of hypertension in the racial disparity of renal cancer incidence.

METHODS

Participants were enrolled in a population-based case-control study in Detroit and Chicago during 2002-2007 (number of cases: 843 whites, 358 blacks; number of controls: 707 whites, 519 blacks). Participants reported their history of hypertension and antihypertensive drug use. We used unconditional logistic regression to calculate odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for demographic characteristics, smoking, body mass index, and family history of cancer.

RESULTS

Hypertension doubled renal cancer risk (OR = 2.0 [CI = 1.7-2.5]) overall. For whites, the OR was 1.9 (CI = 1.5-2.4), whereas for blacks it was 2.8 (2.1-3.8) (P for interaction = 0.11). ORs increased with time after hypertension diagnosis (P for trend <0.001), reaching 4.1 (CI = 2.3-7.4) for blacks and 2.6 (CI = 1.7-4.1) for whites after 25 years. ORs for poorly controlled hypertension were 4.5 (CI = 2.3-8.8) for blacks and 2.1 (CI = 1.2-3.8) for whites. If these estimates correctly represent causal effects and if, hypothetically, hypertension could be prevented entirely among persons aged 50-79 years, the black/white disparity in renal cancer could be reversed among women and reduced by two-thirds among men.

CONCLUSIONS

Hypertension is a risk factor for renal cancer among both blacks and whites, and might explain a substantial portion of the racial disparity in renal cancer incidence. Preventing and controlling hypertension might reduce renal cancer incidence, adding to the known benefits of blood pressure control for heart disease and stroke reduction, particularly among blacks.

Renal cell cancer among African Americans: an epidemiologic review

Incidence rates for renal cell cancer, which accounts for 85% of kidney cancers, have been rising more rapidly among blacks than whites, almost entirely accounted for by an excess of localized disease. This excess dates back to the 1970s, despite less access among blacks to imaging procedures in the past. In contrast, mortality rates for this cancer have been virtually identical among blacks and whites since the early 1990s, despite the fact that nephrectomy rates, regardless of stage, are lower among blacks than among whites. These observations suggest that renal cell cancer may be a less aggressive tumor in blacks. We have reviewed the epidemiology of renal cell cancer, with emphasis on factors which may potentially play a role in the observed differences in incidence and mortality patterns of renal cell cancer among blacks and whites. To date, the factors most consistently, albeit modestly, associated with increased renal cell cancer risk in epidemiologic studies among whites--obesity, hypertension, cigarette smoking--likely account for less than half of these cancers, and there is virtually no epidemiologic evidence in the literature pertaining to their association with renal cell cancer among blacks. There is a long overdue need for detailed etiologic cohort and case-control studies of renal cell cancer among blacks, as they now represent the population at highest risk in the United States. In particular, investigation of the influence on renal cell cancer development of hypertension and chronic kidney disease, both of which occur substantially more frequently among blacks, is warranted, as well as investigations into the biology and natural history of this cancer among blacks.

Hypertension, diuretics and antihypertensives in relation to bladder cancer

The aim of this study is to investigate the relationships between hypertension, hypertension medication and bladder cancer risk in a population-based case-control study conducted in Los Angeles. Non-Asians between the ages of 25 and 64 years with histologically confirmed bladder cancers diagnosed between 1987 and 1996 were identified through the Los Angeles County Cancer Surveillance Program. A total of 1585 cases and their age-, gender- and race-matched neighborhood controls were included in the analyses. Conditional logistic regression models were used to examine the relationship between history of hypertension, medication use and bladder cancer risk. A history of hypertension was not related to bladder cancer; however, among hypertensive individuals, there was a significant difference in bladder cancer risk related to the use of diuretics or antihypertensive drugs (P for heterogeneity = 0.004). Compared with individuals without hypertension, hypertensive individuals who regularly used diuretics/antihypertensives had a similar risk [odds ratio (OR) 1.06; 95% confidence interval (CI) 0.86-1.30], whereas untreated hypertensive subjects had a 35% reduction in risk (OR: 0.65; 95% CI: 0.48-0.88). A greater reduction in bladder cancer risk was observed among current-smokers (OR: 0.43; 95% CI: 0.27-0.71) and carriers of GSTM1-null (homozygous absence) genotypes (OR: 0.43; 95% CI: 0.22-0.85). Similarly, among smokers with GSTM1-null genotype, levels of 4-aminobiphenyl-hemoglobin adducts were significantly lower among untreated hypertensive individuals (45.7 pg/g Hb) compared with individuals without hypertension (79.8 pg/g Hb) (P = 0.009). In conclusion, untreated hypertension was associated with a reduced risk of bladder cancer.

A Unique Pair of Monozygotic Twins with Concordant Clear Cell Renal Cell Carcinoma: A Case Report

Introduction: Genetic predisposition to clear cell renal cell carcinoma (ccRCC) has been linked to disorders such as von Hippel-Lindau (VHL) syndrome. While twin research is a classic approach for elucidating genetic and environmental contributions to disease, no monozygotic twin-pair concordant for ccRCC in the absence of VHL syndrome has been previously reported in the literature or in major twin registries. Clinical Picture: We describe a unique monozygotic twin-pair concordant for ccRCC, with discordant but early ages of onset of 25 and 38 respectively. Cytogenetic studies and direct sequencing for VHL gene mutations in the second twin proved unremarkable. Conclusions: This is the first reported case of monozygotic twins concordant for ccRCC in the absence of VHL gene mutation. The early yet discordant, age of onset of disease in both twins suggests both genetic and environmental contributions to ccRCC. Key words: Gene-environment interaction, Kidney cancer, von Hippel Lindau syndrome

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.

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.

Risk factors for renal cell cancer in a Japanese population

The incidence of renal cell cancer has been increasing worldwide. Although the incidence of renal cell cancer in Japan is lower than the rates in the other industrialized countries, there is no doubt that it is increasing. In this paper, we would like to introduce the result of our studies, which evaluate the risk factors for renal cell cancer in Japan. Hypertension, diabetes mellitus, kidney diseases, fondness for fatty food and black tea showed an increased risk of renal cell carcinoma while an intake of starchy roots such as taro, sweet potato and potato reduced the risk of renal cell carcinoma. In Japan, however, drinking black tea may be a surrogate for westernized dietary habits while eating starchy roots may be a surrogate for traditional Japanese dietary habits. Further studies may be needed to evaluate risk factors for renal cell cancer because the number of renal cancer cases was small in our studies in spite of a large population-based cohort study.

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.

Energy intake, physical activity, energy balance, and cancer: epidemiologic evidence

Energy intake, physical activity, and obesity are modifiable lifestyle factors. This chapter reviews and summarizes the epidemiologic evidence on the relation of energy intake, physical activity, and obesity to cancer. High energy intake may increase the risk of cancers of colon-rectum, prostate (especially advanced prostate cancer), and breast. However, because physical activity, body size, and metabolic efficiency are highly related to total energy intake and expenditure, it is difficult to assess the independent effect of energy intake on cancer risk. There are sufficient evidences to support a role of physical activity in preventing cancers of the colon and breast, whereas the association is stronger in men than in women for colon cancer and in postmenopausal than in premenopausal women for breast cancer. The evidence also suggests that physical activity likely reduces the risk of cancers of endometrium, lung, and prostate (to a lesser extent). On the other hand, there is little or no evidence that the risk of rectal cancer is related to physical activity, whereas the results have been inconsistent regarding the association between physical activity and the risks of cancers of pancreas, ovary and kidney. Epidemiologic studies provide sufficient evidence that obesity is a risk factor for both cancer incidence and mortality. The evidence supports strong links of obesity with the risk of cancers of the colon, rectum, breast (in postmenopausal women), endometrium, kidney (renal cell), and adenocarcinoma of the esophagus. Epidemiologic evidence also indicates that obesity is probably related to cancers of the pancreas, liver, and gallbladder, and aggressive prostate cancer, while it seems that obesity is not associated with lung cancer. The role of obesity in other cancer risks is unclear.

Epidemiology of kidney cancer

Some tumors are known to have a definite cause-effect etiology, but renal cell carcinoma (RCC) is not one of them precisely. With regard to RCC we can only try to identify some clinical and occupational factors as well as substances related to tumorigenesis. Smoking, chemical carcinogens like asbestos or organic solvents are some of these factors that increase the risk of the RCC. Viral infections and radiation therapy have also been described as risk factors. Some drugs can increase the incidence of RCC as well as other neoplasms. Of course, genetics plays an outstanding role in the development of some cases of kidney cancer. Chronic renal failure, hypertension, and dialysis need to be considered as special situations. Diet, obesity, lifestyle, and habits can also increase the risk of RCC. The aim of this review is to summarize the well-defined causes of renal cell carcinoma.

Obesity and cancer

The prevalence of obesity, defined as a BMI of > or =30.0 kg/m2, has increased substantially over previous decades to about 20% in industrialized countries, and a further increase is expected in the future. Epidemiological studies have shown that obesity is a risk factor for: post-menopausal breast cancer; cancers of the endometrium, colon and kidney; malignant adenomas of the oesophagus. Obese subjects have an approximately 1.5-3.5-fold increased risk of developing these cancers compared with normal-weight subjects, and it has been estimated that between 15 and 45% of these cancers can be attributed to overweight (BMI 25.0-29.9 kg/m2) and obesity in Europe. More recent studies suggest that obesity may also increase the risk of other types of cancer, including pancreatic, hepatic and gallbladder cancer. The underlying mechanisms for the increased cancer risk as a result of obesity are unclear and may vary by cancer site and also depend on the distribution of body fat. Thus, abdominal obesity as defined by waist circumference or waist:hip ratio has been shown to be more strongly related to certain cancer types than obesity as defined by BMI. Possible mechanisms that relate obesity to cancer risk include insulin resistance and resultant chronic hyperinsulinaemia, increased production of insulin-like growth factors or increased bioavailability of steroid hormones. Recent research also suggests that adipose tissue-derived hormones and cytokines (adipokines), such as leptin, adiponectin and inflammatory markers, may reflect mechanisms linked to tumourigenesis.

Body size and renal cell cancer incidence in a large US cohort study

Renal cell cancer (RCC) incidence has increased in the United States over the past three decades. The authors analyzed the association between body mass index (BMI) and invasive RCC in the National Institutes of Health (NIH)-AARP Diet and Health Study, a large, prospective cohort aged 50-71 years at baseline initiated in 1995-1996, with follow-up through December 2003. Detailed analyses were conducted in a subcohort responding to a second questionnaire, including BMI at younger ages (18, 35, and 50 years); weight change across three consecutive age intervals; waist, hip, and waist-to-hip ratio; and height at age 18 years. Incident RCC was diagnosed in 1,022 men and 344 women. RCC was positively and strongly related to BMI at study baseline. Among subjects analyzed in the subcohort, RCC associations were strongest for baseline BMI and BMI recalled at age 50 years and were successively attenuated for BMI recalled at ages 35 and 18 years. Weight gain in early (18-35 years of age) and mid- (35-50 years of age) adulthood was strongly associated with RCC, whereas weight gain after midlife (age 50 years to baseline) was unrelated. Waist-to hip ratio was positively associated with RCC in women and with height at age 18 years in both men and women.

Epidemiologic and socioeconomic burden of metastatic renal cell carcinoma (mRCC): a literature review

Renal cell carcinoma (RCC), the most common form of kidney cancer, initially has an asymptomatic clinical course; 25-30% of patients present with metastatic disease at time of diagnosis. Worldwide incidence and mortality rates are rising at a rate of approximately 2-3% per decade. Metastatic RCC (mRCC) is one of the most treatment-resistant malignancies; outcomes are generally poor and median survival after diagnosis is less than one year. Surgery and chemotherapy have limited or no effect, leaving mRCC patients underserved in the realm of cancer treatment. As the world's population ages and the prevalence of risk factors (obesity, hypertension) increases, the burden of mRCC is predicted to increase significantly. With a shift in treatment of mRCC to novel therapies, such as molecularly targeted therapies (MTTs) (e.g., sorafenib and sunitinib), clinicians, payers, and other healthcare decision-makers must re-evaluate the optimal role for new treatments. Timely understanding of the burden of mRCC on individuals and society clearly is needed at this juncture. Using a comprehensive literature review, we assessed the epidemiologic, economic, and health-related quality of life (HRQOL) burdens of mRCC. The annual incidence of mRCC in major European countries, the US, and Japan ranges from 1500 to 8600 cases. However, prevalence data were lacking. The estimated economic burden of mRCC is large; $107-$556 million (2006 USD) in the US and $446 million-$1.6 billion (2006 USD) collectively in select countries worldwide. MTTs have potential to reduce the burden of mRCC and provide substantial value beyond their clinical effectiveness.

Association between obesity and kidney disease: a systematic review and meta-analysis

This study aimed to comprehensively assess epidemiologic evidence on the relation between obesity and kidney disease (KD). From 247 retrieved articles via PubMed (1980-2006), 25 cohorts, 3 cross-sectional, and 19 case-control studies met inclusion criteria. Related data were extracted using a standardized protocol. We estimated the pooled relative risk (RR) and 95% confidence interval (95% CI) of KD for each body mass index (BMI) category compared with normal weight using meta-analysis models. Population attributable risk was also calculated. Compared with normal-weight individuals (18.5<BMI<25), overweight individuals (25< or =BMI<30) had elevated risk for KD (RR=1.40; 95% CI 1.30-1.50); obese individuals were at much higher risk (RR=1.83 (1.57-2.13)). Obesity in women was associated with a higher risk than in men (RR=1.92 (1.78-2.07) vs 1.49 (1.36-1.63); P<0.001). Results from cohort studies in patient populations and cross-sectional and case-control studies all indicated a positive association between BMI and risks for KD outcomes. We estimated that 24.2% and 33.9% of KD cases among US men and women, respectively, and in industrialized countries, 13.8% in men and 24.9% in women, could be related to overweight and obesity. Obesity increases the risk for KD in the general population, and the association appears to be stronger in women than in men. Obesity adversely affects the progress of KD among patients with kidney-related diseases.