The Copenhagen case-control study of bladder cancer. II. Effect of coffee and other beverages

Low daily water intake profile-is it a contributor to disease?

Few previous review articles have focused on the associations between inadequate daily water intake (LOW) or urinary biomarkers of dehydration (UD; low urine volume or high urine osmolality) and multiple diseases. Accordingly, we conducted manual online searches (47 key words) of the PubMed, Embase, and Google Scholar databases with these inclusion criteria: English language, full-text, peer reviewed, no restriction on research design, and three publications minimum. Initially, 3,903 articles were identified based on their titles and abstracts. Evaluations of full length .pdf versions identified 96 studies that were acceptable for inclusion. We concluded that the evidence is insufficient or conflicting for seven disorders or diseases (i.e. suggesting the need for additional clarifying research) and it is lacking for all-cause mortality. Differential characterizations among women and men have been reported in the results of nine studies involving five diseases. Finally, the evidence for associations of LOW or UD is strong for both kidney stones and type 2 diabetes with hyperglycemia. This suggests that great public health value (i.e. reduced disease risk) may result from increased daily water intake-a simple and cost-effective dietary modification.

[Correlation between daily fluid intake behavioral habits and pathological characteristics of upper tract urothelial carcinoma]

OBJECTIVE

To investigate the correlation between drinking habits and pathological characteristics of patients with upper tract urothelial carcinoma (UTUC).

METHODS

A preoperative questionnaire survey was conducted to understand the drinking habits of UTUC patients who were admitted to the Department of Urology, Peking University First Hospital for radical nephroureterectomy within one year from August 2020 to July 2021, and statistical analysis was performed in combination with their postoperative pathological characteristics. The statistical procedure was performed using SPSS 22.0 software, and firstly, the preliminary analysis was performed one by one using the columnar χ² test on the pathological characteristics of UTUC tumors as the dependent variable and the factors related to patients' general information, past history and drinking habits as the independent variables, and the independent variables that met P < 0.2 between the case and control groups for each dependent variable were specified for screening. The screened variables were included in the binary Logistic regression analysis. A difference of P < 0.05 was used to indicate a statistically significant difference.

RESULTS

A total of 239 patients, 134 males and 105 females, with a mean age of (68.1±9.98)years and a median disease duration of 4.8 months, were included in this study. Multifactorial Logistic regression results suggested that after adjusting for the effects of other variables, UTUC patients who had the habit of drinking at least once every hour during the daytime had a significantly increased risk of high grade (G3) tumors(OR=1.941, 95%CI: 0.352-1.029, P < 0.01); these patients also had a significantly decreased risk of multifocal UTUC tumors (OR=0.344, 95% CI: 1.18-5.582, P=0.004). The patients who had the habit of drinking over 100 mL water each time had a significantly decreased risk of mutifocal UTUC incidence (OR=0.477, 95%CI: 0.225-1.012, P=0.046). Patients who pay attention to daily water intakes had a significantly increased risk of renipelvic carcinoma (OR=2.530, 95%CI: 1.434-4.463, P=0.001) and a significantly decreased risk of ureteral carcinoma (OR=0.314, 95%CI: 0.172-0.573, P < 0.01). Other variables included in the regression model did not differ significantly in their effects on the occurrence of tumor pathological characteristics.

CONCLUSION

Having the awareness of drinking water every 1 h during the day, drinking over 100 mL water each time, having the awareness of daily drinking habits correlated significantly with pathological characteristics of UTUC such as the presence of G3 tumor, multifocal tumors and location of the tumor. This conclusion still needs to be verified by subsequent trials with higher levels of evidence.

Consumption of sugar-sweetened beverages and fruit juice and human cancer: a systematic review and dose-response meta-analysis of observational studies

Background: Several epidemiological studies have assessed the association of sugary drinks consumption with cancer, but the results remain controversial. Objective: We performed this analysis to evaluate possible causal relationship between sugary drinks consumption and cancer risk and mortality. Methods: We searched PubMed, Embase, and Web of Science databases in English. Observational studies evaluating the association of sugary drinks intake with cancer were included. Random-effects meta-analysis was used to calculate the risk estimates. Results: A total of 71 observational articles with 32 case-control and 39 cohort studies were included in the meta-analysis. 60 addressed cancer risk, and 11 reported cancer mortality. Compared with the lowest level, the highest level of sugar-sweetened beverages (SSB) consumption showed an increased overall cancer risk (RR=1.12 95% CI: 1.06-1.19, P=0.000) and mortality (RR=1.07 95% CI: 1.01-1.14, P=0.029), and fruit juice intake showed a positive association with cancer risk in cohort studies (RR=1.06 95% CI: 1.01-1.11, P=0.013). Subgroup analyses based on cancer type indicated that risk of breast cancer, hepatocellular carcinoma, colorectal cancer, and prostatic cancer mortality had a positive association with SSB consumption. For dose-response analysis, evidence of a linear association was found between overall cancer risk and SSB or fruit juice consumption, and the risk increase by 4% for one servings/d increment in SSB intake and 14% in fruit juice. Conclusions: Our findings suggest the consumption of sugary beverages may increase the risk and mortality of cancer, especially risk of breast cancer, hepatocellular carcinoma, colorectal cancer, and prostatic cancer, and mortality of breast cancer, though the evidence was limited.

The association between coffee consumption and bladder cancer in the bladder cancer epidemiology and nutritional determinants (BLEND) international pooled study

Background

Inconsistent results for coffee consumption and bladder cancer (BC) risk have been shown in epidemiological studies. This research aims to increase the understanding of the association between coffee consumption and BC risk by bringing together worldwide case–control studies on this topic.

Methods

Data were collected from 13 case–control comprising of 5,911 cases and 16,172 controls. Pooled multivariate odds ratios (ORs), with corresponding 95% confidence intervals (CIs), were obtained using multilevel logistic regression models. Furthermore, linear dose–response relationships were examined using fractional polynomial models.

Results

No association of BC risk was observed with coffee consumption among smokers. However, after adjustment for age, gender, and smoking, the risk was significantly increased for never smokers (ever vs. never coffee consumers: OR_model2 1.30, 95% CI 1.06–1.59; heavy (> 4 cups/day) coffee consumers vs. never coffee consumers: OR_model2 1.52, 95% CI 1.18–1.97, p trend = 0.23). In addition, dose–response analyses, in both the overall population and among never smokers, also showed a significant increased BC risk for coffee consumption of more than four cups per day. Among smokers, a significant increased BC risk was shown only after consumption of more than six cups per day.

Conclusion

This research suggests that positive associations between coffee consumption and BC among never smokers but not smokers.

Total fluid consumption and risk of bladder cancer: a meta-analysis with updated data

With meta-analysis we tented to reveal the potential relationship between daily fluid consumption and bladder cancer risk, and to find out a recommendation on daily fluid intake. Databases of the Web of Science, PubMed and EMBASE were searched then 21 case-control and 5 cohort studies were included. Stratified analyses on gender, region, time of subjects recruiting and fluid quantity were performed as well as dose-response meta-analysis. Comparing the highest exposure category with the lowest in each study, no association appeared when all data pooled together (p=0.50), but a significant OR of 1.46 (1.02-2.08, p=0.04) was found in male subgroup. For different regions, the summarized OR was 1.44 (1.10-1.89) in American case-control studies, 1.87 (1.20-2.90) in European male subgroup and 0.24 (0.10-0.60) in Asia. There was a significant relationship that each increment 1000ml daily consumption would increase the risk by 28.6% in European male (p=0.007). Similarly every additional 1000ml consumption may increase the OR by 14.9% in American people but the association wasn't that strong (p=0.057). Stratified analyses showed fluid consumption over 3000ml/day in American residents and 2000ml/day in European male resulted in OR>1 with statistical significance. In conclusion, a relationship between higher fluid intake and higher bladder cancer risk was observed in European male and American residents and a limitation to <2000ml and <3000ml per day are recommended respectively.

Tea Consumption and Risk of Bladder Cancer: A Dose-Response Meta-Analysis

Background and Objective: Controversial results of the association between tea (black tea, green tea, mate, and oolong tea) consumption and risk of bladder cancer were reported among epidemiological studies. Thus, we performed a meta-analysis of observational studies to investigate the association. Methods: We searched the PubMed and Embase for studies of tea consumption and bladder cancer that were published in any language up to March, 2016. Cohort or case-control studies were included in the meta-analysis. All statistical analyses were performed in Stata 12.0 software. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the relationship between tea consumption and risk of bladder cancer. Results: Totally, 25 case-control studies (15 643 cases and 30 795 controls) and seven prospective cohort studies (1807 cases and 443 076 participants) were included. The meta-analysis showed that tea consumption was not significantly associated with bladder cancer risk (OR = 0.96, 95% CI 0.86-1.06) (in a comparison of highest vs. lowest category). No non-linearity association was observed between tea consumption and bladder cancer risk (P = 0.51 for non-linearity). Specific analysis for black tea, green tea, and mate yielded similar results. The dose-response analysis showed the summary OR for an increment of 1 cup/day of tea consumption was 1.01 (95% CI 0.97-1.05). Conclusion: Results based on current meta-analysis indicated that no significant association was observed between tea consumption and risk of bladder cancer.

Dietary water intake and bladder cancer risk: An Italian case-control study

Previous studies on the relationship between fluid intake and risk of bladder cancer have generally focused on beverages, and results have been inconsistent. We investigated the relationship between water intake and bladder cancer risk, considering water from both beverages and foods. Between 2003 and 2014 we conducted a multicenter hospital-based case-control study in Italy on 690 cases and 665 frequency-matched controls. Water intake for beverages and foods was computed using the Italian food composition database. Odds ratios (ORs) and the corresponding 95% confidence intervals (95%CIs) for water intake were estimated by unconditional multiple logistic regression models, adjusting for major risk factors for bladder cancer. In the control group, the 64.7% of water intake derived from beverages and 35.4% from foods. Comparing the highest with the lowest quartile of intake, water from beverages (OR=1.14; 95%CI: 0.82-1.59) and water from foods (OR=0.88; 95%CI: 0.61-1.28) were not significantly associated with bladder cancer risk. Some specific water sources showed significant associations with bladder cancer risk (e.g. water from vegetables, OR=0.58; 95%CI: 0.40-0.86). However, these associations may be due to the effect of other components contained in beverages and foods rather than to the water content itself. Considering the intakes of water from both beverages and foods, total water intake was not associated with bladder cancer risk.

Coffee consumption and bladder cancer: a meta-analysis of observational studies

Controversial results of the association between coffee consumption and bladder cancer (BC) risk were reported among epidemiological studies. Therefore, we conducted this meta-analysis to clarify the association. Relevant studies were identified according to the inclusion criteria. Totally, 34 case-control studies and 6 cohort studies were included in our meta-analysis. The overall odds ratio (OR) with 95% confidence interval (CI) between coffee consumption and BC risk was 1.33 (95% CI 1.19 to 1.48). The summary ORs of BC for an increase of 1 cup of coffee per day were 1.05 (95% CI 1.03 to 1.06) for case-control studies and 1.03 (95% CI 0.99 to 1.06) for cohort studies. The overall ORs for male coffee drinkers, female coffee drinkers and coffee drinkers of both gender were 1.31 (95% CI: 1.08 to 1.59), 1.30 (95% CI: 0.87 to 1.96) and 1.35 (95% CI: 1.20 to 1.51). Compared with smokers (OR = 1.24, 95% CI: 0.91 to 1.70), non-smokers had a higher risk (OR = 1.72, 95% CI: 1.25 to 2.35) for BC. Results of this meta-analysis suggested that there was an increased risk between coffee consumption and BC. Male coffee drinkers and non-smoking coffee drinkers were more likely to develop BC.

Relationship between bladder cancer and total fluid intake: a meta-analysis of epidemiological evidence

Objectives

Epidemiological findings regarding the association between total fluid intake and bladder cancer risk have yielded varying results. Our objective is to examine the possible associations between total fluid intake and bladder cancer risk.

Methods

Databases searched include the EMBASE and PUBMED, from inception to February 2014, with no limits on study language. We also reviewed the reference lists of identified studies. Stratified analyses were performed. A random-effect model was used to summarize the estimates of odds ratio (OR) with 95% confidence intervals (CI).

Results

Overall,17 case-control and four cohort studies were included. The overall OR of bladder cancer for the highest versus the lowest fluid intake was 1.06 (95% CI: 0.88-1.27). In the subgroup analyses, the overall ORs for coffee, green, and black tea intake were 1.17 (95% CI: 1.03-1.33), 0.76 (95% CI: 0.66-0.95), and 0.80 (95% CI: 0.65-0.97), respectively. A significantly decreased risk was observed in Asian people (OR 0.27; 95% CI: 0.10-0.72). Among smokers, a suggestive inverse association was observed between total fluid intake and overall bladder cancer risk (OR 0.80; 95% CI: 0.62-1.02).

Conclusions

Although this meta-analysis suggested that greater consumption of fluid may have a protective effect on bladder cancer in Asian people, there was no convincing evidence on this association because of the limitations of the individual trials.

A meta-analysis of tea consumption and the risk of bladder cancer

OBJECTIVE

Previous studies on the association between tea consumption and bladder cancer risk have only illustrated contradictory results. The role of tea in bladder carcinogenesis still remains conflicting. In order to illustrate the potential relationship between tea consumption and bladder cancer, a meta-analysis of case-control and cohort studies was conducted.

METHODS

Eligible studies were retrieved via both computerized searches and review of references. Stratified analyses on types of tea, gender, study design, ethnicity and smoking status were performed. Fixed- or random-effect models were used to summarize the estimates of OR with 95% CIs.

RESULTS

Seventeen studies were eligible for our analysis. No statistical significance was detected between tea consumption and bladder cancer risk when comparing the highest with the lowest intake of tea (OR = 0.825, 95% CI 0.652-1.043). In the subgroup of green tea, we observed it illustrated a protective effect on bladder cancer (OR = 0.814, 95% CI 0.678-0.976).

CONCLUSION

Our analysis indicated that green tea may have a protective effect on bladder cancer in Asian people. Further studies need to be conducted to better clarify the biological mechanisms.

Tea consumption and risk of bladder cancer: a meta-analysis

Background

Tea consumption has been reported to be associated with an decreased risk of several types of cancers. However, the results based on epidemiological studies on the association of tea consumption with bladder cancer were inconsistent. This meta-analysis was undertaken to evaluate the relationship between tea consumption and bladder cancer risk.

Methods

Eligible studies were retrieved via both computer searches and review of references. The summary relative risk (RR) with 95% confidence interval (CI) was calculated.

Results

Twenty three studies met the inclusion criteria of the meta-analysis. No association with bladder cancer was observed in either overall tea consumption group (OR =0.94, 95% CI 0.85-1.04) or subgroups stratified by sex, study design, geographical region or tea types.

Conclusions

Our findings did not support that tea consumption was related to the decreased risk of bladder cancer.

A dose-response meta-analysis of coffee consumption and bladder cancer

BACKGROUND

A number of studies have examined the association between coffee consumption and risk of bladder cancer, but uncertainty about the dose-response relationship remains.

MATERIALS AND METHODS

A comprehensive search was performed to identify all observational studies providing quantitative estimates between bladder cancer risk and coffee consumption. Dose-response relationship was assessed by restricted cubic spline model and bivariate random-effect meta-regression.

RESULTS

23 case-control studies with 7690 cases and 13,507 controls, and 5 cohort studies with 700 cases and 229,099 participants, met the inclusion criteria. Compared with non-drinkers and for case-control studies, the pooled smoking-adjusted RRs(95% CI) of bladder cancer were 1.07(1.02-1.13) for 1 cup/day, 1.15(1.05-1.26) for 2 cups/day, 1.22(1.08-1.38) for 3 cups/day, and 1.29(1.12-1.48) for 4 cups/day. For cohort studies, the pooled smoking-adjusted RRs of bladder cancer were 1.09(95% CI, 0.89-1.34) for 1 cup/day, 1.13(95% CI, 0.82-1.55) for 2 cups/day, 1.09(95% CI, 0.77-1.56) for 3 cups/day, and 1.01(95% CI, 0.69-1.48) for 4 cups/day.

CONCLUSIONS

Although data from case-control studies suggested that coffee was a risk factor for bladder cancer, there was no conclusive evidence on this association because of inconsistencies between case-control and cohort studies.

Fluid intake and the risk of urothelial cell carcinomas in the European Prospective Investigation into Cancer and Nutrition (EPIC)

Results from previous studies investigating the association between fluid intake and urothelial cell carcinomas (UCC) are inconsistent. We evaluated this association among 233,236 subjects in the European Prospective Investigation into Cancer and Nutrition (EPIC), who had adequate baseline information on water and total fluid intake. During a mean follow-up of 9.3 years, 513 first primary UCC occurred. At recruitment, habitual fluid intake was assessed by a food frequency questionnaire. Multivariable hazard ratios were estimated using Cox regression stratified by age, sex and center and adjusted for energy intake, smoking status, duration of smoking and lifetime intensity of smoking. When using the lowest tertile of intake as reference, total fluid intake was not associated with risk of all UCC (HR 1.12; 95%CI 0.86-1.45, p-trend = 0.42) or with risk of prognostically high-risk UCC (HR 1.28; 95%CI 0.85-1.93, p-trend = 0.27) or prognostically low-risk UCC (HR 0.93; 95%CI 0.65-1.33, p-trend = 0.74). No associations were observed between risk of UCC and intake of water, coffee, tea and herbal tea and milk and other dairy beverages. For prognostically low-risk UCC suggestions of an inverse association with alcoholic beverages and of a positive association with soft drinks were seen. Increased risks were found for all UCC and prognostically low-risk UCC with higher intake of fruit and vegetable juices. In conclusion, total usual fluid intake is not associated with UCC risk in EPIC. The relationships observed for some fluids may be due to chance, but further investigation of the role of all types of fluid is warranted.

Nutrition, total fluid and bladder cancer

Bladder cancer is a major health concern for older males in Western populations. About 30 years ago there was a suggestion that nutrition may have a role in the aetiology of the disease. Although the literature has been accumulating since then, owing to heterogeneity between studies results have often been inconsistent and unclear. The aim of this paper was to present an updated summary of the scientific evidence on the association between nutrition, total fluid intake and bladder cancer. A search of computerized databases, PubMed, ISI, Embase and Cochrane Library, was conducted to identify all epidemiological studies published between 1966 and October 2007. The level of scientific evidence for the various nutritional factors and total fluid intake was ranked according to the number of studies reporting a statistically significant association and the existence of mechanistic evidence. The levels of association were based on a ranking of statistically significant relative risks. Fruit and yellow-orange vegetables, particularly carrots and selenium, are probably associated with a moderately reduced risk of bladder cancer. Citrus fruits and cruciferous vegetables were also identified as having a possible protective effect. Possible risk factors are salted and barbecued meat, pork, total fat, pickled vegetables, salt, soy products, spices and artificial sweeteners. No clear association could be determined for beef, eggs, processed meats and total fluid intake. In conclusion, specific fruit and vegetables may act to reduce the risk of bladder cancer. Future studies on bladder cancer should investigate the effect of food categorization, amount and gender.

Epidemiology of urinary bladder cancer: from tumor development to patient’s death

Urinary bladder cancer (UBC) ranks ninth in worldwide cancer incidence. It is more frequent in men than in women. We review the main established/proposed factors, both environmental and genetic, associated with bladder cancer etiology and prognosis. Data were extracted from previous reviews and original articles identified from PubMed searches, reference lists, and book chapters dealing with the reviewed topics. Evaluation and consensus of both the contribution of each factor in bladder cancer burden and the appropriateness of the available evidences was done during an ad hoc meeting held during the 18th Congress of the European Society for Urological Research. Cigarette smoking and specific occupational exposures are the main known causes of UBC. Phenacetin, chlornaphazine and cyclophosphamide also increase the risk of bladder cancer. Chronic infection by Schistosoma haematobium is a cause of squamous cell carcinoma of the bladder. NAT2 slow acetylator and GSTM1 null genotypes are associated with an increased risk of this cancer. Vegetables and fresh fruits protect against this tumor. Regarding prognosis, there is little knowledge on the predictive role of environmental exposures and genetic polymorphisms on tumor recurrence and progression and patient's death. Although active tobacco smoking is the most commonly studied factor, no definitive conclusion can be drawn from the literature. More research is needed regarding the effect of complex etiological factors in bladder carcinogenesis. Subgroup analysis according to stage, grade, and molecular features may help in identifying specific etiological and prognostic factors involved in different bladder cancer progression pathways.

Non-alcoholic beverages and risk of bladder cancer in Uruguay

BACKGROUND

Bladder cancer is the fourth most frequent malignancy among Uruguayan men. A previous study from Uruguay suggested a high risk of bladder cancer associated with maté drinking. We conducted an additional case-control study in order to further explore the role of non-alcoholic beverages in bladder carcinogenesis.

METHODS

In the time period 1996-2000, 255 incident cases with transitional cell carcinoma of the bladder and 501 patients treated in the same hospitals and in the same time period were frequency matched on age, sex, and residence. Both cases and controls were face-to-face interviewed on occupation, tobacco smoking, alcohol drinking and intake of maté, coffee, tea, and soft drinks. Statistical analysis was carried out by unconditional multiple logistic regression.

RESULTS

Ever maté drinking was positively associated with bladder cancer (odds ratio [OR] 2.2, 95% confidence interval [CI] 1.2-3.9) and the risk increased for increasing duration and amount of maté drinking. Both coffee and tea were strongly associated with bladder cancer risk (OR for coffee drinking 1.6, 95% CI 1.2-2.3; OR for tea drinking 2.3, 95% CI 1.5-3.4). These results were confirmed in a separate analysis of never-smokers.

CONCLUSION

Our results suggest that drinking of maté, coffee and tea may be risk factors for bladder carcinoma in Uruguay.

Mechanisms of disease: The epidemiology of bladder cancer

Mortality from bladder cancer has shown downward trends over the last 2 decades in several western European countries (albeit 10-15 years later than similar trends in the US), but is still increasing in some eastern European countries. Tobacco smoking and occupational exposure to aromatic amines are the two major established environmental risk factors for bladder cancer. Controlling exposure to these factors has been an important contributor to the reduction in bladder cancer mortality, particularly among men. Diet could influence bladder carcinogenesis, as many compounds contained in foods--and their metabolites--are excreted through the urinary tract. Fruit and vegetable consumption was inversely related with bladder cancer in many studies, but no consistent association has emerged between intake of related micronutrients and reduced risk of bladder cancer. Other widely investigated lifestyle habits are probably not associated with risk of developing bladder cancer (e.g. coffee consumption, artificial sweetener use, hair dyes) or are difficult to assess (e.g. fluid intake). Infections and stones in the urinary tract might cause chronic irritation of the bladder epithelium, and thus increase bladder cancer risk. First-degree relatives of bladder cancer patients have a 50-100% increased relative risk of developing the disease, a risk that could be even higher when the proband is diagnosed at an early age.

Electrochemical studies of (−)-epigallocatechin gallate and its interaction with DNA

In this paper, an electrochemical investigation of (-)-epigallocatechin gallate (EGCG) and its interaction with DNA is presented. Via an electrochemical approach assisted by ultraviolet-visible (UV-Vis) spectroscopy, we propose that EGCG can intercalate into DNA strands forming a nonelectroactive complex, which results in the decrease of the anodic peak current of EGCG. Meanwhile, an electrochemical study with the DNA-Cu(II)-EGCG system shows that damage to DNA can be recognized electrochemically via the increase in the anodic peak current resulting from the oxidation of guanine and adenine bases. The damage can also be recognized spectrophotometrically via an increase in the 260 nm absorption band. In addition, it was found that EGCG is able to discriminate dsDNA from ssDNA, making a potential electrochemical indicator for the detection of DNA hybridization events. A rapid and convenient method of detecting EGCG was also developed in this work.

Bladder cancer risk in sales workers: artefact or cause for concern?

BACKGROUND

A large number of epidemiological studies have reported positive associations between bladder cancer and sales occupations. We investigated whether these findings are likely to be due to chance, confounding or publication bias, or may involve causal associations.

METHODS

Studies reporting bladder cancer risk-estimates for sales occupations were reviewed. Using meta-analyses we assessed heterogeneity and publication bias, and derived summary estimates.

RESULTS

Eighteen publications were identified, reporting 85 risk-estimates for sales-work. Meta-estimates were elevated for men (odds ratio (OR) 1.11, 95% confidence interval (CI) 1.01-1.21) and women (OR = 1.36, 95% CI = 1.11-1.67). The estimate was heterogeneous for men (p(Q-test) <0.01, women: 0.18) and indicated publication bias for women (p(Egger-test) <0.01, men: 0.40). When including only smoking-adjusted estimates reported irrespective of the strength of the association, the summary estimate for generic groups of sales workers was 0.99 (95% CI 0.90-1.08) for men, and 1.18 (95% CI = 0.99-1.39) for women, without statistically significant heterogeneity or publication bias. For women, risk was positively associated with longer duration of sales-employment in three studies.

CONCLUSIONS

Publication bias explained most of the reported increased bladder cancer risk, but sales-work still appeared to be associated with a small risk in women. Possible causal factors include lower frequency of urination and reduced fluid intake.

Bladder cancer: Epidemiology, staging and grading, and diagnosis

Bladder cancer is a heterogeneous disease with a variable natural history. At one end of the spectrum, low-grade Ta tumors have a low progression rate and require initial endoscopic treatment and surveillance but rarely present a threat to the patient. At the other extreme, high-grade tumors have a high malignant potential associated with significant progression and cancer death rates. In the Western world, bladder cancer is the fourth most common malignancy in men and the eighth most common in women. In Europe and the United States, bladder cancer accounts for 5% to 10% of all malignancies in men. The risk of developing bladder cancer at <75 years of age is 2% to 4% for men and 0.5% to 1% in women compared with the risk of lung cancer, for example, which is 8% in men and 2% in women. For the geographic and temporal comparison of bladder cancer incidence, it is crucial to separate the low-grade from the high-grade tumors. In epidemiologic studies on risk factors for bladder cancer, it is important to distinguish the low-grade Ta tumors from high-grade carcinoma in situ (CIS) and tumors >T1. Current studies do not support the routine screening for bladder cancer. However, prospective long-term studies are required to evaluate the benefits of bladder cancer screening, particularly in those at high risk. After assessing all available evidence, the Epidemiology and Diagnosis Committee has made recommendations on various diagnostic issues, including pathologic evaluation, urinary cytology, and imaging studies. Optimal resection techniques, role of repeat transurethral resection in high-grade T1 tumors, random bladder biopsy, and prostatic urethral biopsy are discussed, and appropriate recommendations are made according to the strength of available evidence.

Total and specific fluid consumption as determinants of bladder cancer risk

We pooled the data from 6 case-control studies of bladder cancer with detailed information on fluid intake and water pollutants, particularly trihalomethanes (THM), and evaluated the bladder cancer risk associated with total and specific fluid consumption. The analysis included 2,729 cases and 5,150 controls. Odds ratios (OR) and 95% confidence intervals (CI) for fluid consumption were adjusted for age, gender, study, smoking status, occupation and education. Total fluid intake was associated with an increased risk of bladder cancer in men. The adjusted OR for 1 l/day increase in intake was 1.08, (95% CI 1.03-1.14, p-value for linear trend <0.001), while no trend was observed in women (OR=1.04, 0.94-1.15; p-value=0.7). OR was 1.33 (1.12-1.58) for men in the highest category of intake (>3.5 l/day) as compared to those in the lowest (<or=2 l/day). An increased risk was associated with intake of tap water. OR for >2 l/day vs. <or=0.5 l/day was 1.46 (1.20-1.78), with a higher risk among men (OR=1.50, 1.21-1.88). No increased risk was observed for the same intake groups of nontap water in men (OR=0.97, 0.77-1.22) or in women (OR=0.85, 0.50-1.42). Increased bladder cancer risks were observed for an intake of >5 cups of coffee daily vs. <5 and for THM exposure, but neither exposure confounded or modified the OR for tap water intake. The association of bladder cancer with tap water consumption, but not with nontap water fluids, suggests that carcinogenic chemicals in tap water may explain the increased risk.

Fluid intake and risk of bladder and other cancers

There are appreciable differences in total fluid intake at the individual and population level, and substantial difficulties in obtaining valid measures of fluid intake. Epidemiological studies have examined the association between fluid intake and different types of cancer. For bladder cancer, fluid consumption has been associated with a moderate increase of risk in some studies, including a multicentric case-control study from the United States, based on about 3000 cases, with a decrease in others, including the Health Professional Follow-up study, or with no material association. The evidence, therefore, is far from consistent. Sources and components of fluids were also different across different types studies. From a biological point of view, a decreased fluid intake could result in a greater concentration of carcinogens in the urine or in a prolonged time of contact with the bladder mucosa because of less frequent micturition. Carcinogenic or anticarcinogenic components of various beverages excreted in the urine may also play a role in the process. It has been suggested that fluid consumption has a favorable effect on colorectal cancer risk. Fluid intake may reduce colon cancer risk by decreasing bowel transit time and reducing mucosal contact with carcinogens. Low fluid intake may also compromise cellular concentration, affect enzyme activity in metabolic regulation, and inhibit carcinogen removal. However, epidemiological data are inadequate for evaluation. Data are sparse and inconsistent for other neoplasms, including breast cancer. The fluid constituent of foods, confounding, interactions and possible influences of specific types of beverages should be investigated further. In conclusion therefore the association between total fluid intake and cancer risk remains still open to debate.

The association between smoking, beverage consumption, diet and bladder cancer: a systematic literature review

In this paper the association between smoking history, beverage consumption, diet and bladder cancer incidence is systematically reviewed. A rating system has been used to summarise the level of scientific evidence (i.e. convincing, probable, possible, and no evidence) and the level of association (i.e. substantially increased, (RR> or =2.5), moderately increased (1.5< or =RR<2.5), slightly increased (1.2< or =RR<1.5), no association (0.8< or =RR<1.2), slightly decreased (0.7< or =RR<0.8), moderately decreased (0.4< or =RR<0.7), and substantially decreased (RR<0.4)). There is convincing evidence that cigarette smoking status, frequency and duration substantially increase the risk of bladder cancer. However, the evidence is not clear for other forms of smoking. A small increased risk for cigar, pipe, and environmental smoking is only possible. There is possible evidence that total fluid intake is not associated with bladder cancer. Although there is convincing evidence for a positive association between alcohol consumption and bladder cancer risk in men, the risk is small and not clinically relevant. Coffee and tea consumption are probably not associated with bladder cancer. The authors conclude that total fruit consumption is probably associated with a small decrease in risk. There is probably no association between total vegetable intake, vitamin A intake, vitamin C intake and bladder cancer and a possibly moderate inverse association with vitamin E intake. Folate is possibly not associated with bladder cancer. There probably is a moderate inverse association between selenium intake and bladder cancer risk.

(−)-Epigallocatechin gallate causes oxidative damage to isolated and cellular DNA

Green tea catechins, especially (-)-epigallocatechin gallate (EGCG), are believed to mediate much of the cancer chemopreventive effects of tea. However, it was reported that green tea catechins enhanced colon carcinogenesis in rats. Experiments using 32P-labeled DNA fragments obtained from human cancer-related genes showed that catechins induced DNA damage in the presence of metals such as Cu(II) and Fe(III) complexes. In the presence of Fe(III)EDTA, the order of DNA damaging ability was EGCG approximately (-)-epigallocatechin>(-)-epicatechin gallate>>catechin. Catechins plus Fe(III)EDTA caused DNA damage at every nucleotide, most likely due to *OH generation from H(2)O(2). In the presence of Cu(II), the order was (-)-epigallocatechin>catechin>EGCG>(-)-epicatechin gallate. Cu(II)-mediated DNA damage by EGCG occurred most frequently at T and G residues, especially of 5'-TG-3' and GG sequences. Catalase and bathocuproine inhibited the Cu(II)-mediated DNA damage, suggesting the involvement of H(2)O(2) and Cu(I). In the presence of metal ions, increased amounts of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) were found in DNA treated with EGCG. Furthermore, EGCG increased amounts of 8-oxodG in HL-60 cells, but not in the H(2)O(2)-resistant clone HP100. When GSH was reduced by L-buthionine-[S, R]-sulfoximine, a low concentration of EGCG increased amounts of 8-oxodG in HL-60 cells, further supporting the involvement of H(2)O(2) in cellular DNA damage. It is concluded that EGCG can induce H(2)O(2) generation and subsequent damage to isolated and cellular DNA, and that oxidative DNA damage may mediate the potential carcinogenicity of EGCG.

Bladder cancer prevention. Part I: what do I tell my patients about lifestyle changes and dietary supplements?

PURPOSE OF REVIEW

Comprehensive reviews of lifestyle changes and dietary supplements that may prevent bladder cancer are needed in order to facilitate discussions between clinicians and patients.

RECENT FINDINGS

Novel data exist that numerous lifestyle/diet and dietary supplements may lower the risk of this disease. For example, reducing arsenic exposure, incorporating dietary changes, and vitamin E supplements continue to accumulate research that supports their use with some patients at a higher risk for this disease. Regardless, smoking cessation seems to have the largest impact on reducing risk and incorporating these other changes after smoking cessation may reduce an individual's risk to an even greater extent.

SUMMARY

However, a large percentage of cases of individuals diagnosed with this cancer apparently have no known etiology. Diets lower in calories or possibly specific sub-types of fat, and higher in fruits and especially vegetables, seem to provide some protection. Other dietary/supplement options may affect risk, but these benefits could be seriously attenuated by smoking. Dietary selenium, but currently not selenium supplements, may also affect risk, especially in non-smokers. Dietary vitamin E, and vitamin E supplements, may provide some protection. Non-selective (e.g. non-steroidal anti-inflammatory drugs) and selective cyclooxygenase-2 inhibitors are generating interest because bladder tumors seem to contain higher concentrations of this enzyme. Drinking-water quality, especially arsenic concentrations, may seriously affect risk. Providing recommendations for patients with regard to some of these lifestyle modifications is currently recommended because the majority of these alterations are also recommended currently for cardiovascular or general oncology disease reduction.

Diet patterns and the risk of renal cell carcinoma

OBJECTIVES

Our objective was to identify food intake patterns that might be associated with the risk of renal cell carcinoma.

DESIGN

A total of 461 cases (210 females, 251 males) were age frequency matched to population controls. Diet factors were created using factor analysis of 69 food items from a food-frequency questionnaire. These factors were modelled using logistic regression to identify those associated with renal cell carcinoma.

SETTING

We investigated the role of diet in the aetiology of renal cell carcinoma using a population-based case--control study conducted in Ontario between 1995 and 1996.

SUBJECTS

Cases were Ontario residents 20 to 74 years of age identified through review of pathology reports in the Ontario Cancer Registry.

RESULTS

A 'dessert' diet factor was positively associated with disease for both sexes (odds ratio estimate (OR) for males = 3.7, 95% confidence interval (CI) 2.0-6.9; OR for females = 1.4, 95% CI 0.8-2.2, for the highest vs. lowest quartile). In males, a 'beef' diet factor was identified and was associated with an increased risk of renal cell carcinoma. Furthermore, a 'juices' diet factor also showed an association with increased risk in males (OR = 1.8, 95% CI 1.0-3.1). For females, a positive association was observed between renal cell carcinoma and an 'unhealthy' diet factor (OR = 1.4, 95% CI 0.8-2.4).

CONCLUSIONS

Our findings confirmed that high-fat and high-protein diets might be risk factors for renal cell carcinoma. The data also suggest an increased risk associated with juice intake, a finding not previously reported.

Coffee and tea consumption and cancers of the bladder, colon and rectum

Coffee has been observed to be associated weakly or not at all with bladder cancer risk, inversely with colon cancer risk, and inconsistently with rectal cancer risk. The association between these cancers and consumption of coffee and tea was examined in a single case-control study conducted in Ontario, Canada from 1992 to 1994. A questionnaire was filled out by 927 bladder cancer cases, 991 colon cancer cases, 875 rectal cancer cases, and 2118 population controls. Although bladder cancer risk was not associated with coffee or tea, risk estimates associated with coffee among subjects who had never smoked were non-significantly increased. Colon cancer risk was inversely associated with coffee. Relative to those drinking less than 1 cup of coffee per day, the odds ratios (OR) for those drinking 1-2 cups was 0.9 (95% CI 0.8-1.1), for those drinking 3-4 cups was 0.8 (95% CI 0.7-1.0), and for those drinking 5 or more cups was 0.7 (95% CI 0.5-0.9); these ORs decreased linearly (P = 0.008). The reduced risk estimates were more pronounced with cancer of the proximal colon than the distal colon. Rectal cancer risk was not associated with either coffee or tea. Coffee consumption was observed to have a different relationship for each of the cancer sites and tea consumption was not related to any cancer site.

Potential lifestyle and dietary supplement options for the prevention and postdiagnosis of bladder cancer

Apart from smoking, certain occupational exposures, and schistosomiasis, little is known about other potential lifestyle risk factors for bladder cancer. Other investigations thus far have also been important because of the large number of individuals who are diagnosed with this cancer that apparently have no known risk factors. Preventing the recurrence of bladder cancer has generated some interest because several preliminary trials have found that a combination dietary supplement of vitamins and minerals or a probiotic agent (Lactobacillus casei) may impact this outcome favorably. Advising patients on some of these lifestyle modifications is currently recommended because the majority of them are also currently recommended for cardiovascular disease reduction.

Fluid consumption and the risk of bladder cancer: results of a multicenter case-control study

A number of studies suggest a relation between fluid consumption and the risk of bladder cancer but results are contradictory. Different theories involving the quantity or the type of fluid consumed have been put forward to explain these relations but mechanisms remain unclear. We conducted a multicenter case-control study in several hospitals in France including 765 cases and 765 matched controls. Information collected by face-to-face interview included quantity and type of beverages consumed from the age of 18 until age at diagnosis, as well as smoking habits. Among men, we observed a slight non-significant increased risk of bladder cancer associated with total fluid intake, irrespectively of tobacco use. This was essentially due to intake of non-alcoholic drinks, coffee and bottled juice or water. Relative risks greater than 1 were observed in relation with coffee consumption. On the other hand, alcohol consumption, especially wine, was associated with relative risks less than unity. No relation could be identified between bladder cancer risk and fluid consumption among women. Our results do not support an association between total fluid consumption and bladder cancer risk. The role of the different types of fluid consumed, confounding factors and bias in the present analysis are discussed.

Are coffee and tea consumption associated with urinary tract cancer risk? A systematic review and meta-analysis

BACKGROUND

Narrative reviews have concluded that there is a small association between coffee consumption and an increased risk of urinary tract cancer, possibly due to confounding by smoking. No association for tea consumption has been indicated. This systematic review attempts to summarize and quantify these associations both unadjusted and adjusted for age, smoking and sex.

METHOD

Thirty-four case-control and three follow-up studies were included in this systematic review. Summary odds ratios (OR) were calculated by meta-regression analyses.

RESULTS

The unadjusted summary OR indicated a small increased risk of urinary tract cancer for current coffee consumers versus non-drinkers. The adjusted summary OR were: 1.26 (95% CI : 1.09-1.46) for studies with only men, 1.08 (95% CI : 0.79-1.46) for studies with only women and 1.18 (95% CI : 1.01-1.38) for studies with men and women combined. Neither unadjusted nor adjusted summary OR provided evidence for a positive association between tea consumption and urinary tract cancer. Even though studies differed in methodology, the results were rather consistent. We did not perform dose-response analyses for coffee and tea consumption due to sparse data.

CONCLUSIONS

In accordance with earlier reviews, we found that coffee consumption increases the risk of urinary tract cancer by approximately 20%. The consumption of tea seems not to be related to an increased risk of urinary tract cancer.

Alcohol consumption and bladder cancer risk: results from The Netherlands Cohort Study

Although several epidemiologic studies have been conducted on alcohol consumption and bladder cancer risk, the risk according to quantity and type of alcohol consumed is not clear. The authors investigated these associations in a large prospective cohort study on diet and cancer among 120,852 subjects in the Netherlands aged 55-69 years at baseline (1986). Subjects completed a questionnaire on risk factors for cancer, including alcohol consumption. Follow-up for incident cancer was established by record linkage to cancer registries. The case-cohort analysis was restricted to a follow-up period of 6.3 years and was based on 594 cases with bladder cancer and 3,170 subcohort members. The authors corrected for age and smoking in multivariable analyses. The incidence rate ratios for men who consumed <5, 5-<15, 15-<30, and > or =30 grams of alcohol per day were 1.49, 1.52, 1.16, and 1.63 compared with nondrinkers, respectively (p for trend = 0.13). Alcohol consumed from beer, wine, and liquor was associated with moderately elevated risks, although most were not statistically significant. The incidence rate ratios for women varied around unity. The results of this study do not suggest an important association between alcohol consumption and bladder cancer risk.

Tea consumption: fluid intake and bladder cancer risk in Southern Taiwan

OBJECTIVES

To determine whether tea consumption and intake of other beverages increases bladder cancer risk.

METHODS

A case-control study was conducted in Kaohsiung, Taiwan between August 1996 and June 1997. Index patients studied were consecutive patients with histologically confirmed, newly diagnosed bladder cancer in two major hospitals. For each patient, 4 controls were selected from patients with non-neoplastic and nonurologic diseases undergoing surgical operations in the same hospital and individually matched by sex, age, and date of admission. Using a structured questionnaire, a trained interviewer interviewed 40 patients and 160 controls. Conditional logistic regression analysis adjusting for ethnicity, family history, and smoking status and matching variables were used to estimate the odds ratio (OR) and 95% confidence interval (CI).

RESULTS

Tea consumption overall was associated with increased bladder cancer risk (OR 3.29, 95% CI 1.34 to 8.05). Compared with non-tea drinkers, the odds ratios of bladder cancer for oolong tea drinkers was 3.00 (95% CI 1.20 to 7.47); for non-oolong tea drinkers (black and/or other green tea), it was 14.86 (95% CI 2.13 to 103.83). The risk was greater among those who began to drink tea before age 40 (OR 9.50, 95% CI 2.39 to 37.75) and those who had been drinking tea for more than 30 years (OR 17.75, 95% CI 3.00 to 105.17). Coffee, tap water, and alcohol consumption were associated with a slightly increased risk, and both soy juice and rice juice consumption were associated with reduced risk; none of these odds ratio estimates were statistically significant, however.

CONCLUSIONS

Our results suggest that tea consumption is associated with an increased risk of bladder cancer.

Fluid intake and the risk of bladder cancer in men

BACKGROUND

Studies in animals have shown that the frequency of urination is inversely associated with the level of potential carcinogens in the urothelium. In humans, an increase in total fluid intake may reduce contact time between carcinogens and urothelium by diluting urinary metabolites and increasing the frequency of voiding. The data on fluid intake in relation to the risk of bladder cancer are inconclusive.

METHODS

We examined the relation between total fluid intake and the risk of bladder cancer over a period of 10 years among 47,909 participants in the prospective Health Professionals Follow-up Study. There were 252 newly diagnosed cases of bladder cancer during the follow-up period. Information on total fluid intake was derived from the reported frequency of consumption of the 22 types of beverages on the food-frequency questionnaire, which was completed by each of the 47,909 participants who were free of cancer in 1986. Logistic-regression analyses were performed to adjust for known and suspected risk factors for bladder cancer.

RESULTS

Total daily fluid intake was inversely associated with the risk of bladder cancer; the multivariate relative risk was 0.51 (95 percent confidence interval, 0.32 to 0.80) for the highest quintile of total daily fluid intake (>2531 ml per day) as compared with the lowest quintile (<1290 ml per day). The consumption of water contributed to a lower risk (relative risk, 0.49 [95 percent confidence interval, 0.28 to 0.86] for > or =1440 ml [6 cups] per day vs. <240 ml [1 cup] per day), as did the consumption of other fluids (relative risk, 0.63 [95 percent confidence interval, 0.39 to 0.99] for >1831 ml per day vs. <735 ml per day).

CONCLUSIONS

A high fluid intake is associated with a decreased risk of bladder cancer in men.

Non-occupational risk factors for cancer of the lower urinary tract in Germany

In a hospital-based case-control study conducted between 1989 and 1992 in Hessen (West Germany) 300 cases (239 male and 61 female) of histologically confirmed cancer of the lower urinary tract (LUT) were individually matched to controls from the same hospitals with respect to sex, age and area of residence. Smoking of cigarettes was associated with an elevated risk of 2.80 in males (95% confidence interval (CI): 1.65-4.76) and 5.33 (95% CI: 1.55-18.33) in females, as compared with nonsmokers. Variables like daily amount of smoked cigarettes, duration of smoking, age at beginning of cigarette smoking and time since smoking cessation showed a clear dose- and time-response relationship in males, but not in females. Elevated risks were observed for higher consumption of coffee, beer and wine, but - especially for the consumption of coffee were drastically reduced after adjustment for smoking. A weak association was found between the daily fluid intake and bladder cancer in males. Among females a significantly decreased odds ratio (OR) of 0.34 (95% CI: 0.11-0.99) was found for a daily fluid intake of more than two liters. Protective effects and risk reductions of approximately 50% were found for the regular intake of raw carrots, kale, salads and fruits. The findings of this investigation support an association between lifestyle factors and cancer of the lower urinary tract.

Cancer rates among drinkers of black tea

Studies in experimental animals have shown that compounds in tea can inhibit the process of carcinogenesis, with the beneficial effects accruing to both green and black teas. Herein epidemiologic studies around the world are reviewed to assess the rates and risks of cancer among black tea drinkers. Ecologic data suggest at most a modest benefit on total cancer, as there is considerable international variation in black tea consumption but generally small differences in overall cancer rates. Cohort studies of tea drinkers and case control studies of specific cancers show mixed results. Consistent dose-related patterns have yet to emerge, although detailed data from these studies on cancer risks according to amount and duration of black tea intake are often limited. Several investigations point to the possibility of somewhat lowered risks of digestive tract cancers among tea drinkers, but the evidence is inconclusive. Further research, especially involving populations with wide ranges of tea consumption, is needed to clarify black tea's impact on cancer risk.

Role of urinary physiology and chemistry in bladder carcinogenesis

Urine is a complex mixture of numerous substances, only some of which are described above. Literally thousands of substances have been identified in normal urine, including a variety of ions, non-ionic substances and macromolecules. Their presence and concentrations are highly variable, dependent on fluid intake and on nutritional, physiological and biochemical influences. Marked diurnal variations exist. Methodologies involved in the collection and analysis of these components can greatly influence the interpretation of the results. The influence of these various parameters in the urine on bladder carcinogenicity can be either direct or indirect. A major difficulty in studying this aspect of urothelial carcinogenesis is that it is essentially impossible to alter only one variable in the urine at a time. Alteration of any one variable results in physiological alteration of several other of the constituents in the urine. In addition, the processes involved in urothelial carcinogenesis frequently involve a complex interaction of multiple variables, such as volume, osmolality, cationic concentration, anionic concentration, quantitative and qualitative differences in protein, and generation of precipitate, crystals or calculi. Thus, it is likely that the actual mechanisms involved in the carcinogenic process with many of these chemicals, particularly those that are non-genotoxic, will involve a complex interaction of several constituents of the urine. Although this poses a formidable obstacle to our understanding in experimental situations as well as in extrapolating to humans, the role of specific factors appears to be discernible and should offer insight into the risk assessment process (Cohen and Ellwein, 1991 a,b and 1992).

Relative importance of risk factors in bladder carcinogenesis: some new results about Mediterranean habits

In the Mediterranean region of France where bladder cancer mortality and incidence are high, a case-control study with 219 male incident cases and 794 randomized, male population-controls was carried out in 1987-89 to investigate bladder cancer risk factors and more specifically, regional factors. A stepwise logistic regression was applied to the data. This investigation confirms the role of tobacco and of certain occupational exposures in bladder carcinogenesis. There was a significant dose-response relationship with lifelong coffee drinking and alcohol consumption; however the risk estimates were only significantly elevated for the heaviest drinkers. The intake of saccharin was not associated with risk of bladder cancer. Infrequent consumption of carrots, spinach, and marrows conferred an increased risk, suggesting a protective effect of vitamin A. Finally, this investigation results in some new hypotheses. The study of residences and birthplaces has revealed a lower risk for those who have lived in a non-Mediterranean area and a higher risk for those born in a Mediterranean area. These features might be explained by some Mediterranean dietary habits, such as a high consumption of spices (odds ratio = 3.64, 95 percent confidence interval = 2.21-5.98).

A cross-national investigation of diet and bladder cancer

The existence of a large unexplained portion of attributable risk, and the marked variation in bladder cancer rates globally, have stimulated an interest in the role of nutrition in cancer of the urinary bladder. For this cross-national comparison study, we had complete data available for 50 countries. Using stepwise regression followed by general linear modelling, age-truncated (45-74 years), world-standardised, sex-specific bladder cancer mortality rates were regressed on an array of nutritional and socioeconomic independent variables in an effort to identify important predictors of bladder cancer mortality. Separate principal components analyses were used to summarise the nutritional and the socioeconomic (SES) variables. In the stepwise analyses, using food scores expressed in kcal/day per capita (as opposed to the nutritional components), total fat consistently entered the model first, and explained the greatest share of variability (R2) for both males and females. General linear models were fitted that included total fat, tobacco, alcohol, the three SES components (comprising seven socioeconomic predictors) and two food categories found significant in stepwise modelling, roots/tubers and vegetable oil. The R2 values were 0.84 for male rates and 0.77 for female rates, meaning that these study factors account for 84% of bladder cancer mortality in men and 77% in women. Substitution of the nutritional components for the foods resulted in general linear models with slightly higher R2 values (0.85 for males, 0.77 for females), but with attenuated fat effects. Results are discussed in light of biological plausibility.

Coffee, cigarette smoking, and bladder cancer in western New York

The association between consumption of coffee and bladder cancer and the effect modification of cigarette smoking was investigated as part of a comprehensive case-control study. The study population consisted of 351 case patients with histologically confirmed transitional cell carcinomas of the bladder among white males and 855 white male control subjects selected from Erie, Niagara, and Monroe counties in New York from 1979 to 1985. Usual diet, coffee consumption, and cigarette use were estimated by comprehensive interviews using a detailed food frequency questionnaire. After adjustment for age, education, and dietary risk factors by multiple logistic regression, risk was found to increase with increasing pack-years of cigarette use with an odds ratio in the highest quartile of 2.7 (95% confidence interval, 1.8 to 4.0) when compared to the lowest quartile. Coffee consumption was associated with an increased risk for bladder cancer among the heaviest coffee drinkers after adjustment for cigarette smoking and other dietary risk factors (odds ratio, 2.1; 95% confidence interval, 1.3 to 3.2). The effect was more pronounced among nonsmokers, especially among those 65 years and older. These findings support the contention that coffee is a weak carcinogen.

Bladder cancer and coffee drinking: a summary of case-control research

An association between coffee drinking and cancer of the lower urinary tract (LUT) was first suggested 20 years ago and has been the subject of many epidemiological studies. We have undertaken a critical review and statistical summary of 35 case-control studies of this association published between 1971 and 1992. Predefined methodological criteria were applied to the available reports. Studies were classified as either meeting the criteria (core studies) or failing to satisfy at least one of the requirements for design or analysis (non-core studies). The summarised data from the 8 core studies showed no evidence of an increase in risk of LUT cancer with coffee drinking in men or women after adjustment for the effects of cigarette smoking (odds ratio 1.07 [95% CI 1.00-1.14] for men, 0.91 [0.81-1.03] for women). The measures of association from the non-core studies were higher on average than those from the core studies, although the inclusion of these data in an overall summarised estimate did not substantially change the findings from the core analysis. We conclude that the best available data do not suggest a clinically important association between the regular use of coffee and development of cancer of the LUT in men or women.

Drinking water, fluid intake, and bladder cancer in western New York

Fluid intake and consumption of specific beverages were investigated in a study of 351 white male cases for whom transitional cell carcinoma of the bladder had been confirmed histologically during the time period from 1979 to 1985. A total of 855 white male controls was selected from Erie, Niagara, and Monroe counties of western New York state. Total fluid consumption was composed of alcoholic beverages, bottled beverages, soda, milk, coffee, tea, all juices, and glasses of tap water. Tap water included coffee, tea, juices, and glasses of water taken directly from the tap. Total fluid consumption was found to be a strong risk factor for bladder cancer when a number of potential confounding risk factors were controlled for. Risks were higher among those who were less than 65 y of age (odds ratio [OR] = 6.3, 95% C.I. = 2.8-14.0). The OR was 3.4 (95% C.I. = 1.8-6.2) for the highest quartile of fluid consumption among those 65 y of age and older. The tap water component was associated with increased risk in both age categories, and there was a clear dose-response relationship. Risks associated with tap water consumption were higher among those who never smoked cigarettes. Both biological and nonbiological explanations for these results are evaluated. The findings suggest implications for public health, but the limitations of the present investigation preclude definitive conclusions and stress the urgency for replication.

Risk factors for renal cell carcinoma: results of a population-based case-control study

For a case-control study of risk factors for renal cell carcinoma, a mailed questionnaire was used to collect data on 518 cases and 1,381 population-based controls in Ontario, Canada. Active cigarette smoking increased risk twofold among males (odds ratio estimate [OR] = 2.0, 95 percent confidence interval (CI) = 1.4-2.8) and females (OR = 1.9, CI = 1.3-2.6). Passive smoking appeared to increase risk somewhat among nonsmokers (males: OR = 1.6, CI = 0.5-4.7; females: OR = 1.7, CI = 0.8-3.4). A high Quetelet index (QI) was associated with a twofold increase in risk in both sexes, although this was based on reported weight at age 25 years for males (OR = 1.9, CI = 1.2-3.1) and five years prior to data collection for females (OR = 2.5, CI = 1.4-4.6). Diuretic use was associated with significantly increased risk among females, but not among males. Phenacetin use increased risk, while acetaminophen use was not associated with altered risk, although few subjects used either compound. Multiple urinary tract infections increased risk, but only significantly in females (OR = 1.9, CI = 1.2-2.9). Our data indicate the need for further exploration of passive smoking and diuretics as risk factors, as well as elucidation of mechanisms by which high lifetime QI and frequent urinary-tract infections might increase risk of this cancer.

Life style and occupational risk factors for bladder cancer in Germany. A case-control study

A hospital-based, case-control study of 531 male and 144 female matched pairs was conducted in Germany to analyze the role of nonoccupational and occupational risk factors in the etiology of tumors of the lower urinary tract (bladder cancer). Smoking of cigarettes was associated with an odds ratio (OR) of 3.6 for men and 3.2 for women, compared with not smoking and showed a significant dose- and time-response relationship for both sexes. Heavy pipe smoking significantly increased the risk (OR = 1.9 in men), and smoking of cigars did not alter the risk of bladder cancer. Controlling for smoking, a significantly twofold or more increase in risk was found for heavy consumption of coffee in both sexes and for heavy intake of beer in males. Increasing levels of total fluid intake were associated with increasing, smoking-adjusted risks in men. Significant associations were found for chronic infection of the lower urinary tract (OR = 1.8), familial history of bladder cancer (OR = 2.5), and frequent consumption of high fat meals (OR = 1.4) among men and for frequent consumption of canned food in both sexes (OR = 1.7 for males, 2.4 for females). With regard to occupational history, significantly elevated odds ratios were found for ever-employment in the printing (5.0), plastics and synthetics (2.6), rubber (2.5), mining (2.0), and dyestuffs (1.9) industries, for exposure to spray paints (2.9), zinc (2.3), chromium/chromate (2.2), oils (1.5), petroleum (1.4), stone dust (1.4) and metal dust/fumes (1.3), and for occupation as mining worker (2.0) and truck driver (1.8) among men. Multivariate logistic regression analysis showed significant contribution of coffee and beer drinking, ingestion of canned food, and familial occurrence of urothelial tumors to the risk of bladder cancer in men after accounting for the effects of tobacco smoking, occupational exposures, and a history of bladder infection. These other variables did not influence the risk attributable to occupational exposures.

Coffee consumption and bladder cancer risk

The relation between consumption of regular and decaffeinated coffee and other methylxanthine-containing beverages and bladder cancer was analysed in a case-control study in two different areas of northern Italy (555 cases and 855 controls). The multivariate relative risk (RR) adjusted for smoking, occupation and sociodemographic variables for coffee drinkers versus non-drinkers was 1.3 (95% CI 1.0-1.8). The RR was 1.2 for one cup of coffee per day, 1.4 for two, 1.5 for three and 1.4 for four or more (P = 0.05). RRs for current drinkers were 1.5 (0.9-2.4) for decaffeinated coffee, 0.9 (0.6-1.2) for tea, and 0.6 (0.3-1.4) for cola. With reference to duration of consumption of coffee, RRs were 1.2 for less than 30 years or 1.4 for 30 years or more. Coffee-related RRs were higher in the older age group and in ex-smokers. Among 105 cases and 338 controls who had never smoked, RRs were 1.9 for one or two cups per day, 1.8 for three and 1.5 for four or more (trend not significant). A higher prevalence of coffee drinking among bladder cancer cases than controls was confirmed, with no clear dose-risk relation.

Diet in the epidemiology of bladder cancer in western New York

We present the dietary epidemiology of bladder cancer while controlling for a number of lifestyle and environmental risk factors in a study of 351 white male cases with histologically confirmed transitional cell carcinoma of the bladder and 855 white male controls selected from Erie, Niagara, and Monroe counties of western New York from 1979 to 1985. Usual diet was estimated by comprehensive interviews with use of a detailed food frequency questionnaire. An increased risk of bladder cancer was associated with higher kilocalorie intake, but only among those under 65 years of age, with the strongest pattern associated with fat intake. Further analyses of fat, carbohydrates, and protein, with adjustment for total kilocalories, resulted in a positive association of risk with fat intake and a decreasing risk with higher protein intake. Of the vitamins, carotenoid consumption appeared to decrease risk with increased consumption for those under 65 years of age. No significant differences between cases and controls were seen for intake of calcium, retinol, thiamin, riboflavin, niacin, vitamin C, vitamin D, and vitamin E. After adjustment for kilocalories and other confounders, higher intake of dietary sodium was associated with increased risk among both age groups, and the trends were statistically significant. The importance of diet in the etiology of bladder cancer is suggested by our findings.

Dietary factors in cancer of the lower urinary tract

This dietary study was based on 195 male and 66 female cases of lower urinary tract cancer, identified in Hawaii between 1977 and 1986. Each case was matched for sex, age, and ethnic group (Caucasian or Japanese) to 2 population-based controls. There was a decrease in risk with increasing levels of consumption of vitamin C in women (p = 0.03) and dark green vegetables in men (p = 0.02). When examined by quartile, the odds ratios for the highest quartile of intake compared to the lowest quartile were 0.4 for women and 0.6 for men, respectively. Although dark green vegetables are a source of carotenoids, the intake of total carotenoids, retinol and total vitamin A was weakly and inconsistently related to risk in both sexes. Among women only, there was also an inverse association with the consumption of regular ground coffee (p = 0.02) but not with other types of coffee. Finally, there were no statistically significant or consistent differences between cases and controls in the intake of artificial sweeteners and tea.