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BackgroundEvidence indicating an association between cigarette smoke exposure and an increase in breast cancer risk highlights the need for health messages that aim to prevent smoking initiation and reduce secondhand smoke (SHS) exposure among adolescent girls. ObjectiveThis study aimed to evaluate the efficacy of targeted gender-sensitive, breast cancer-specific, Web-based messages about the increased risk of breast cancer associated with cigarette smoke exposure. Outcomes assessed 6 months postmessage delivery included nonsmoking adolescent girls’ knowledge of the link between cigarette smoke exposure and breast cancer, perceptions of breast cancer risk associated with cigarette smoke, smoking behavior and intentions, and stage of change related to avoidance of secondhand smoke. MethodsA prospective randomized controlled trial was used to compare standard (control) messages with targeted gender- and Aboriginal status-sensitive, breast cancer-specific (intervention) messages. Messages were delivered online to 618 nonsmoking girls, aged 13 to 15 years, clustered in 74 Canadian secondary schools. ResultsCompared with the control group, girls in the intervention group were significantly more likely to report that breast cancer is an illness caused by cigarette smoke (adjusted relative risk [ARR] 1.33, 95% CI 1.05-1.68) and to agree that exposure to SHS increases their risk of breast cancer (ARR 1.10, 95% CI 1.02-1.20). No significant effects were observed for a change in smoking status, intention to try smoking, or stage of change related to avoidance of SHS. ConclusionsCompared with standard messages, targeted gender-sensitive, breast cancer-specific messages had a stronger influence on girls’ knowledge and perceived risk of cigarette smoke exposure as a risk factor for breast cancer. Brief information-based interventions delivered over the Internet have the potential to provide effective health promotion that could be broadly disseminated and lead to long-term effects on girls’ knowledge and risk perceptions about cigarette exposure and breast cancer.

BackgroundRecent evidence indicates a causal link between both active smoking and secondhand smoke (SHS) exposure and breast cancer (BC). ObjectiveThe objective of the present study was to evaluate the initial reactions of girls and boys to tailored Web-based messages that describe the relationship between SHS and BC, using a parallel, single-blinded cluster randomized controlled trial. MethodsThis trial was nested within a cycle of an ongoing longitudinal study of 1498 students from 74 secondary schools. Self-reported assessments were used to evaluate the impact of study messages on participants’ risk perception and interest in obtaining additional information after participants were randomized by schools to control or intervention groups. The intervention group received a tailored visual message (based on gender and Aboriginal status) about BC and tobacco smoke. The control group received a standard visual message about smoking and cancer. ResultsSHS exposure was identified as a BC risk factor by 380/1488 (25.54%) participants, during the preintervention analysis. Compared to the female participants in the control group (491/839, 58.5%), girls who received the intervention (339/649, 52.2%) were 14% more likely to agree that exposure to SHS increased their BC risk (relative risk [RR] 1.14, 95% CI 1.07-1.21). Nonsmoking girls who received the intervention were 14% more likely to agree that starting smoking would increase their BC risk (RR 1.14, 95% CI 1.07-1.21). Compared to the male participants in control group (348/839, 41.5%), boys who received the intervention (310/649, 47.8%) were 10% more likely to agree that girls’ exposure to SHS increased their BC risk (RR 1.10, 95% CI 1.02-1.18). Compared to controls, girls who received the intervention were 52% more likely to request additional information about SHS and BC (RR 1.52, 95% CI 1.12-2.06). ConclusionsBrief gender-sensitive messages delivered via the Internet have the potential to increase awareness and to stimulate information seeking about the risk for BC associated with SHS.

BackgroundEvidence from epidemiological studies on the role of tea drinking in gastric cancer risk remains inconsistent. We aimed to investigate and quantify the relationship between tea consumption and gastric cancer in the Stomach cancer Pooling (StoP) Project consortium.MethodsA total of 9438 cases and 20,451 controls from 22 studies worldwide were included. Odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) of gastric cancer for regular versus non-regular tea drinkers were estimated by one and two-stage modelling analyses, including terms for sex, age and the main recognised risk factors for gastric cancer.ResultsCompared to non-regular drinkers, the estimated adjusted pooled OR for regular tea drinkers was 0.91 (95% CI: 0.85-0.97). When the amount of tea consumed was considered, the OR for consumption of 1-2 cups/day was 1.01 (95% CI: 0.94-1.09) and for >3 cups/day was 0.91 (95% CI: 0.80-1.03). Stronger inverse associations emerged among regular drinkers in China and Japan (OR: 0.67, 95% CI: 0.49-0.91) where green tea is consumed, in subjects with H. pylori infection (OR: 0.68, 95% CI: 0.58-0.80), and for gastric cardia cancer (OR: 0.64, 95% CI: 0.49-0.84).ConclusionOur results indicate a weak inverse association between tea consumption and gastric cancer.

A low intake of fruits and vegetables is a risk factor for gastric cancer, although there is uncertainty regarding the magnitude of the associations. In our study, the relationship between fruits and vegetables intake and gastric cancer was assessed, complementing a previous work on the association betweenconsumption of citrus fruits and gastric cancer. Data from 25 studies (8456 cases and 21 133 controls) with information on fruits and/or vegetables intake were used. A two-stage approach based on random-effects models was used to pool study-specific adjusted (sex, age and the main known risk factors for gastric cancer) odds ratios (ORs) and the corresponding 95% confidence intervals (CIs). Exposure-response relations, including linear and nonlinear associations, were modeled using one- and two-order fractional polynomials. Gastric cancer risk was lower for a higher intake of fruits (OR: 0.76, 95% CI: 0.64-0.90), noncitrus fruits (OR: 0.86, 95% CI: 0.73-1.02), vegetables (OR: 0.68, 95% CI: 0.56-0.84), and fruits and vegetables (OR: 0.61, 95% CI: 0.49-0.75); results were consistent across sociodemographic and lifestyles categories, as well as study characteristics. Exposure-response analyses showed an increasingly protective effect of portions/day of fruits (OR: 0.64, 95% CI: 0.57-0.73 for six portions), noncitrus fruits (OR: 0.71, 95% CI: 0.61-0.83 for six portions) and vegetables (OR: 0.51, 95% CI: 0.43-0.60 for 10 portions). A protective effect of all fruits, noncitrus fruits and vegetables was confirmed, supporting further dietary recommendations to decrease the burden of gastric cancer.

At present, analysis of diet and bladder cancer (BC) is mostly based on the intake of individual foods. The examination of food combinations provides a scope to deal with the complexity and unpredictability of the diet and aims to overcome the limitations of the study of nutrients and foods in isolation. This article aims to demonstrate the usability of supervised data mining methods to extract the food groups related to BC. In order to derive key food groups associated with BC risk, we applied the data mining technique C5.0 with 10-fold cross-validation in the BLadder cancer Epidemiology and Nutritional Determinants study, including data from eighteen case-control and one nested case-cohort study, compromising 8320 BC cases out of 31 551 participants. Dietary data, on the eleven main food groups of the Eurocode 2 Core classification codebook, and relevant non-diet data (i.e. sex, age and smoking status) were available. Primarily, five key food groups were extracted; in order of importance, beverages (non-milk); grains and grain products; vegetables and vegetable products; fats, oils and their products; meats and meat products were associated with BC risk. Since these food groups are corresponded with previously proposed BC-related dietary factors, data mining seems to be a promising technique in the field of nutritional epidemiology and deserves further examination.

The consumption of processed meat has been associated with noncardia gastric cancer, but evidence regarding a possible role of red meat is more limited. Our study aims to quantify the association between meat consumption, namely white, red and processed meat, and the risk of gastric cancer, through individual participant data meta-analysis of studies participating in the "Stomach cancer Pooling (StoP) Project". Data from 22 studies, including 11,443 cases and 28,029 controls, were used. Study-specific odds ratios (ORs) were pooled through a two-stage approach based on random-effects models. An exposure-response relationship was modeled, using one and two-order fractional polynomials, to evaluate the possible nonlinear association between meat intake and gastric cancer. An increased risk of gastric cancer was observed for the consumption of all types of meat (highest vs. lowest tertile), which was statistically significant for red (OR: 1.24; 95% CI: 1.00-1.53), processed (OR: 1.23; 95% CI: 1.06-1.43) and total meat (OR: 1.30; 95% CI: 1.09-1.55). Exposure-response analyses showed an increasing risk of gastric cancer with increasing consumption of both processed and red meat, with the highest OR being observed for an intake of 150 g/day of red meat (OR: 1.85; 95% CI: 1.56-2.20). This work provides robust evidence on the relation between the consumption of different types of meat and gastric cancer. Adherence to dietary recommendations to reduce meat consumption may contribute to a reduction in the burden of gastric cancer.

BackgroundInconsistent 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.MethodsData 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.ResultsNo 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: ORmodel2 1.30, 95% CI 1.06-1.59; heavy (> 4 cups/day) coffee consumers vs. never coffee consumers: ORmodel2 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.ConclusionThis research suggests that positive associations between coffee consumption and BC among never smokers but not smokers.

BackgroundFew studies have modeled smoking histories by combining smoking intensity and duration to show what profile of smoking behavior is associated with highest risk of bladder cancer. This study aims to provide insight into the association between smoking exposure history and bladder cancer risk by modeling both smoking intensity and duration in a pooled analysis.MethodsWe used data from 15 case-control studies included in the bladder cancer epidemiology and nutritional determinants study, including a total of 6,874 cases and 17,727 controls. To jointly interpret the effects of intensity and duration of smoking, we modeled excess odds ratios per pack-year by intensity continuously to estimate the risk difference between smokers with long duration/low intensity and short duration/high intensity.ResultsThe pattern observed from the pooled excess odds ratios model indicated that for a fixed number of pack-years, smoking for a longer duration at lower intensity was more deleterious for bladder cancer risk than smoking more cigarettes/day for a shorter duration. We observed similar patterns within individual study samples.ConclusionsThis pooled analysis shows that long duration/low intensity smoking is associated with a greater increase in bladder cancer risk than short duration/high intensity smoking within equal pack-year categories, thus confirming studies in other smoking-related cancers and demonstrating that reducing exposure history to a single metric such as pack-years was too restrictive.

BackgroundIn 2012, more than 400,000 urinary bladder cancer cases occurred worldwide, making it the 7(th) most common type of cancer. Although many previous studies focused on the relationship between diet and bladder cancer, the evidence related to specific food items or nutrients that could be involved in the development of bladder cancer remains inconclusive. Dietary components can either be, or be activated into, potential carcinogens through metabolism, or act to prevent carcinogen damage.Methods/designThe BLadder cancer, Epidemiology and Nutritional Determinants (BLEND) study was set up with the purpose of collecting individual patient data from observational studies on diet and bladder cancer. In total, data from 11,261 bladder cancer cases and 675,532 non-cases from 18 case-control and 6 cohort studies from all over the world were included with the aim to investigate the association between individual food items, nutrients and dietary patterns and risk of developing bladder cancer.DiscussionThe substantial number of cases included in this study will enable us to provide evidence with large statistical power, for dietary recommendations on the prevention of bladder cancer.

OBJECTIVES: The role of diet in the etiology of breast cancer is not well understood despite extensive research. In the majority of this work, a single nutrient-based approach has been used which does not take into account combinations of food that are consumed. An alternative to the single nutrient approach is to identify patterns in the dietary intake information and relate these patterns to disease incidence. This investigation characterized dietary patterns among participants of a Canadian case-control study and related these dietary patterns to the incidence of breast cancer. METHODS: Dietary and other risk factor data from cases and controls of the Canadian National Enhanced Cancer Surveillance System were collected using self-administered questionnaires. Principal component factor analysis was used to classify individuals based on their dietary patterns. The relationship between these dietary patterns and breast cancer was evaluated using logistic regression. The derived odds ratios and their 95% confidence limits were adjusted for several factors, such as smoking, alcohol intake, environmental tobacco smoke exposure and obesity. RESULTS: In the 2,009 cases and 2,086 controls, three dietary patterns were identified: western, healthy and vitamin. The highest quartile of the 'healthy' dietary pattern was related to a 22% decrease in breast cancer risk (95% CI: 0.61-1.00), relative to the lowest quartile. The fourth quartile of the 'vitamin' dietary pattern was associated with a 14% decrease in breast cancer risk (95% CI: 0.70-1.04) relative to the first. No statistically significant associations between the 'western' dietary pattern and breast cancer were found. These associations were neither confounded nor modified by menopausal status. CONCLUSION: Our analyses reveal that individual dietary items tend to cluster together in such a way that there are three distinct dietary patterns in this sample of Canadian women. Some of these patterns, in turn, were associated with the risk of breast cancer. KEY WORDS: Breast cancer; case-control study; principal factor component analysis; dietary patterns OBJECTIFS: On connait mal le role du regime dans l'etiologie du cancer du sein malgre le grand nombre d'etudes sur le sujet. Dans la majorite de ces etudes, on utilise une demarche axee sur un nutriment particulier, ce qui ne tient pas compte des combinaisons d'aliments qui sont consommees. Une option de rechange a la demarche axee sur un seul nutriment consiste a reperer les grandes tendances de l'information sur les apports alimentaires et a les lier aux structures d'incidence des maladies. Notre enquete a caracterise les schemas alimentaires des participantes d'une etude castemoins canadienne et les ont lies a l'incidence du cancer du sein. METHODE: Des donnees sur le regime alimentaire et d'autres facteurs de risque provenant de cas et de temoins du Systeme national de surveillance accrue du cancer ont ete recueillies a l'aide de questionnaires a remplir soimeme. Nous avons utilise l'analyse factorielle en composantes principales pour classifier les repondantes d'apres leurs habitudes alimentaires. Nous avons evalue la relation entre ces schemas alimentaires et le cancer du sein au moyen d'analyses de regression logistique. Les rapports de cotes derives et leurs intervalles de confiance de 95% ont ete ajustes selon plusieurs facteurs, dont le tabagisme, la consommation d'alcool, l'exposition a la fumee secondaire du tabac et l'obesite. RESULTATS: Chez les 2 009 cas et les 2 086 temoins, nous avons defini trois schemas alimentaires : occidental, sain et vitamine. Le quartile superieur du schema alimentaire << sain >> etait lie a une reduction de 22% du risque de cancer du sein (IC de 95% : 0,61-1,00), comparativement au quartile inferieur. Le quatrieme quartile du schema alimentaire << vitamine >> etait associe a une reduction de 14% du risque de cancer du sein (IC de 95% : 0,70-1,04) comparativement au premier. Nous n'avons trouve aucune association significative entre le schema alimentaire << occidental >> et le cancer du sein. Ces associations n'etaient ni faussees, ni modifiees par le statut menopausique. CONCLUSION: Nos analyses revelent que les choix alimentaires individuels ont tendance a former des grappes qui dessinent trois schemas alimentaires distincts dans cet echantillon de Canadiennes. Certains de ces schemas etaient a leur tour associes au risque de cancer du sein. MOTS CLES: tumeurs du sein; etudes cas-temoins; analyse factorielle en composantes principales; habitudes alimentaires La traduction du resume se trouve a la fin de l'article. Can J Public Health 2016;107(1):e49-e55 doi: 10.17269/CJPH.107.5230, Breast cancer is a global health concern, with incidence rates steady or climbing in high-income countries and both incidence and mortality rates increasing in other countries. (1) In Canada, the [...]

OBJECTIVE: Radon is an important risk factor for lung cancer. Here we use maps of the geographic variation in radon to estimate the lung cancer risk associated with living in high radon areas of Canada. METHODS: Geographic variation in radon was estimated using two mapping methods. The first used a Health Canada survey of 14,000 residential radon measurements aggregated to health regions, and the second, radon risk areas previously estimated from geology, sediment geochemistry and aerial gamma-ray spectrometry. Lung cancer risk associated with living in these radon areas was examined using a population-based case-control study of 2,390 lung cancer cases and 3,507 controls collected from 1994-1997 in eight Canadian provinces. Residential histories over a 20-year period were used in combination with the two mapping methods to estimate ecological radon exposures. Hierarchical logistic regression analyses were used to estimate odds ratios for lung cancer incidence, after adjusting for a comprehensive set of individual and geographic covariates. RESULTS: Across health regions in Canada, significant variation in average residential radon concentrations (range: 16-386 Bq/[m.sup.3]) and in high geological-based radon areas (range: 0-100%) is present. In multivariate models, a 50 Bq/[m.sup.3] increase in average health region radon was associated with a 7% (95% CI: -6-21%) increase in the odds of lung cancer. For every 10 years that individuals lived in high radon geological areas, the odds of lung cancer increased by 11% (95% CI: 1-23%). CONCLUSIONS: These findings provide further evidence that radon is an important risk factor for lung cancer and that risks are unevenly distributed across Canada. KEY WORDS: Radon; lung cancer; geographic; case-control; Canada OBJECTIF: Le radon est un important facteur de risque du cancer du poumon. Nous utilisons ici des cartes de variation spatiale du radon pour estimer le risque de cancer du poumon associe au fait de vivre dans les regions du Canada fortement exposees au radon. METHODE: Nous avons estime la variation spatiale du radon a l'aide de deux methodes de cartographie. La premiere a fait appel a une enquete de Sante Canada regroupant 14 000 mesures du radon dans les habitations par region sanitaire, et la deuxieme, a des estimations anterieures des regions exposees au radon par la geologie, la geochimie sedimentaire et la spectrometrie gamma aeroportee. Nous avons examine le risque de cancer du poumon associe au fait de vivre dans ces zones exposees au radon a l'aide d'une etude populationnelle cas-temoins menee entre 1994 et 1997 aupres de 2 390 cas de cancer du poumon et de 3 507 temoins dans huit provinces canadiennes. Nous avons combine les lieux de residence des sujets au cours des 20 annees precedentes avec les deux methodes de cartographie pour estimer les expositions ecologiques au radon. Des analyses de regression logistique hierarchiques ont permis d'estimer les rapports de cotes de l'incidence du cancer du poumon, apres avoir tenu compte d'un ensemble exhaustif de covariables individuelles et geographiques. RESULTATS : Les regions sanitaires du Canada different considerablement en ce qui a trait a leurs concentrations moyennes en radon dans les habitations (intervalle : 16-386 Bq/[m.sup.3]) et aux zones geologiques fortement exposees au radon (intervalle : 0-100 %). Dans les modeles multivaries, une hausse de 50 Bq/[m.sup.3] du radon dans une region sanitaire moyenne etait associee a une hausse de 7 % (IC de 95 % : -6-21 %) de la probabilite de cancer du poumon. Pour chaque tranche de 10 ans pendant laquelle les sujets avaient vecu dans des zones geologiques fortement exposees au radon, la probabilite du cancer du poumon augmentait de 11 % (IC de 95 % : 1-23 %). CONCLUSIONS : Ces constatations sont des preuves supplementaires que le radon est un important facteur de risque du cancer du poumon, et que les risques sont inegalement repartis au Canada. MOTS CLES : radon; tumeurs du poumon; regions geographiques; etudes cas-temoins; Canada, Radon is a colourless, odourless, naturally occurring gas released from the breakdown of uranium in soils. Exposure to radon occurs primarily indoors, where levels can accumulate to high concentrations. The [...]