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1.
Cancer Causes Control ; 31(6): 583-599, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32314107

RESUMO

PURPOSE: The purpose of this study was to investigate associations between pesticide exposures and risk of Hodgkin lymphoma (HL) using data from the North American Pooled Project (NAPP). METHODS: Three population-based studies conducted in Kansas, Nebraska, and six Canadian provinces (HL = 507, Controls = 3886) were pooled to estimate odds ratios and 95% confidence intervals for single (never/ever) and multiple (0, 1, 2-4, ≥ 5) pesticides used, duration (years) and, for select pesticides, frequency (days/year) using adjusted logistic regression models. An age-stratified analysis (≤ 40/ > 40 years) was conducted when numbers were sufficient. RESULTS: In an analysis of 26 individual pesticides, ever use of terbufos was significantly associated with HL (OR: 2.53, 95% CI 1.04-6.17). In age-stratified analyses, associations were stronger among those ≤ 40 years of age. No significant associations were noted among those > 40 years old; however, HL cases ≤ 40 were three times more likely to report ever using dimethoate (OR: 3.76 95% CI 1.02-33.84) and almost twice as likely to have ever used malathion (OR: 1.86 95% CI 1.00-3.47). Those ≤ 40 years of age reporting use of 5 + organophosphate insecticides had triple the odds of HL (OR: 3.00 95% CI 1.28-7.03). Longer duration of use of 2,4-D, ≥ 6 vs. 0 years, was associated with elevated odds of HL (OR: 2.59 95% CI 1.34-4.97). CONCLUSION: In the NAPP, insecticide use may increase the risk of HL, but results are based on small numbers.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Doença de Hodgkin/epidemiologia , Praguicidas , Adulto , Canadá/epidemiologia , Humanos , Kansas/epidemiologia , Nebraska/epidemiologia
2.
BMC Cancer ; 20(1): 171, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32126982

RESUMO

BACKGROUND: Silica and asbestos are recognized lung carcinogens. However, their role in carcinogenesis at other organs is less clear. Clearance of inhaled silica particles and asbestos fibers from the lungs may lead to translocation to sites such as the bladder where they may initiate carcinogenesis. We used data from a Canadian population-based case-control study to evaluate the associations between these workplace exposures and bladder cancer. METHODS: Data from a population-based case-control study were used to characterize associations between workplace exposure to silica and asbestos and bladder cancer among men. Bladder cancer cases (N = 658) and age-frequency matched controls (N = 1360) were recruited within the National Enhanced Cancer Surveillance System from eight Canadian provinces (1994-97). Exposure concentration, frequency and reliability for silica and asbestos were assigned to each job, based on lifetime occupational histories, using a combination of job-exposure profiles and expert review. Exposure was modeled as ever/never, highest attained concentration, duration (years), highest attained frequency (% worktime) and cumulative exposure. Odds ratios (OR) and their 95% confidence intervals (CI) were estimated using adjusted logistic regression. RESULTS: A modest (approximately 20%) increase in bladder cancer risk was found for ever having been exposed to silica, highest attained concentration and frequency of exposure but this increase was not statistically significant. Relative to unexposed, the odds of bladder cancer were 1.41 (95%CI: 1.01-1.98) times higher among men exposed to silica at work for ≥27 years. For asbestos, relative to unexposed, an increased risk of bladder cancer was observed for those first exposed ≥20 years ago (OR:2.04, 95%CI:1.25-3.34), those with a frequency of exposure of 5-30% of worktime (OR:1.45, 95%CI:1.06-1.98), and for those with < 10 years of exposure at low concentrations (OR:1.75, 95%CI:1.10-2.77) and the lower tertile of cumulative exposure (OR:1.69, 95%CI:1.07-2.65). However, no clear exposure-response relationships emerged. CONCLUSIONS: Our results indicate a slight increase in risk of bladder cancer with exposure to silica and asbestos, suggesting that the effects of these agents are broader than currently recognized. The findings from this study inform evidence-based action to enhance cancer prevention efforts, particularly for workers in industries with regular exposure.


Assuntos
Asbestos/efeitos adversos , Doenças Profissionais/epidemiologia , Dióxido de Silício/efeitos adversos , Neoplasias da Bexiga Urinária/epidemiologia , Adulto , Idoso , Canadá , Estudos de Casos e Controles , Medicina Baseada em Evidências , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/induzido quimicamente , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/estatística & dados numéricos , Neoplasias da Bexiga Urinária/induzido quimicamente
3.
Occup Environ Med ; 76(9): 668-671, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31413189

RESUMO

OBJECTIVES: The causes of kidney cancer are not well understood though occupational exposures are thought to play a role. Crystalline silica is a known human carcinogen, and despite previous links with kidney disease, there have been few studies investigating its association with kidney cancer. We addressed this research gap using a population-based case-control study of Canadian men. METHODS: Questionnaire data were obtained from individuals with histologically confirmed kidney cancer, and population-based controls recruited from eight Canadian provinces (1994-1997). An industrial hygienist characterised participants' lifetime occupational exposure, and their confidence in the assessment (possibly, probably or definitely exposed) to silica on three dimensions (intensity, frequency and duration), and cumulative exposure was estimated. Logistic regression was used to estimate ORs and 95% CIs, adjusting for potential confounders. RESULTS: Nearly half of the 689 kidney cancer cases (49%) and 2369 controls (44%) had ever been occupationally exposed to crystalline silica. In a fully adjusted model, workers ever-exposed to silica had a slightly increased risk of kidney cancer relative to those who were unexposed (OR 1.10, 95% CI 0.92 to 1.32). Odds were modestly (and generally not statistically significantly) increased for models with duration of exposure and cumulative exposure, though exposure-response relationships were not evident. CONCLUSIONS: Our findings do not provide evidence that occupational exposure to crystalline silica increases risk of kidney cancer in men.


Assuntos
Neoplasias Renais/epidemiologia , Exposição Ocupacional , Dióxido de Silício/efeitos adversos , Adulto , Idoso , Canadá/epidemiologia , Estudos de Casos e Controles , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Inquéritos e Questionários
4.
Environ Int ; 122: 104-116, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30522823

RESUMO

BACKGROUND: Exposure to organophosphate ester (OPE) flame retardants and plasticizers is widespread and is of concern due to their toxicity. OBJECTIVES: To investigate relationships between and within OPE concentrations in air, dust, hands, electronic product wipes and urinary metabolites with the goal of identifying product sources and exposure pathways. METHODS: Women in Toronto and Ottawa, Canada, provided a urine sample, two sets of hand wipes, access to their homes for air and dust sampling, and completed a questionnaire. OPE concentrations were obtained for air and floor dust in the bedroom (n = 51) and most used room (n = 26), hand wipes (n = 204), and surface wipes of handheld (n = 74) and non-handheld electronic devices (n = 125). All air, dust and wipe samples were analyzed for 23 OPE compounds; urine samples (n = 44) were analyzed for 8 OPE metabolites. RESULTS: Five-8 OPEs were detected in >80% of samples depending on the sample type. OPE median concentrations in hand wipes taken 3 weeks apart were not significantly different. Palms had higher concentrations than the back of hands; both were significantly correlated. Concentrations of 9 OPEs were significantly higher in surface wipes of handheld than non-handheld electronic devices. Six OPEs in hand wipes were significantly correlated with cell phone wipes, with two to four OPEs significantly correlated with tablet, laptop and television wipes. Multiple regression models using hand wipes, cell phone wipes and dust explained 8-33% of the variation in creatinine-adjusted urinary metabolites; air concentrations did not have explanatory power. OPEs in cell phone wipes explained the greatest variation in urinary metabolites. CONCLUSIONS: Handheld electronic devices, notably cell phones, may either be sources or indicators of OPE exposure through hand-to-mouth and/or dermal uptake.


Assuntos
Telefone Celular , Exposição Ambiental , Retardadores de Chama , Organofosfatos , Plastificantes , Adulto , Canadá , Cidades , Poeira/análise , Feminino , Humanos , Organofosfatos/metabolismo , Organofosfatos/urina
5.
Cancer Med ; 7(11): 5478-5487, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30318772

RESUMO

BACKGROUND: Two germ line Fc-γ receptor (FCGR) polymorphisms, rs1801274 [FCGR2A; His(H)131Arg(R)] and rs396991 [FCGR3A; Phe(F)158Val(V)], produce altered proteins through amino acid substitutions. We previously reported that the FCGR2A H/H genotype was associated with longer overall survival (OS) in cetuximab-treated chemotherapy-refractory patients with metastatic colorectal cancer. Here, we aimed to replicate and extend this finding in the Canadian Clinical Trials Group CO.20 trial. METHODS: After germ line DNA genotyping, polymorphic relationships with survival were assessed using log-rank tests and hazard ratios (HR) from Cox proportional hazard models, adjusting for known prognostic factors. The dominant genetic inheritance model was used for the main analysis. RESULTS: Of 592 wild-type KRAS patients treated with cetuximab, those with the FCGR2A H/H genotype (n = 165, 28%) had improved OS (HR: 0.66, P < 0.001; median absolute benefit, 1.3 months) compared to those with R/- genotype (n = 427, 72%). Patients with H/R had intermediate results under a codominant genetic inheritance model (HR: 0.72, P = 0.003). No significant associations were found between FCGR3A genotype and OS. In an exploratory analysis, patients with the combination of FCGR2A H/H + FCGR3A F/F genotype had significantly better OS (HR: 0.33, P = 0.003; median absolute benefit, 12.5 months) than patients with the combination of double-variant R/R + V/V genotype. Progression-free survival results were similar to OS. Toxicity rates were not associated with either polymorphism. CONCLUSIONS: The FCGR2A genotype was associated with efficacy but not with toxicity in wild-type KRAS, cetuximab-treated colorectal cancer patients. FCGR3A genotype may modulate the relationship between FCGR2A polymorphism and outcome. FCGR2A is a promising biomarker for clinical management for these patients.


Assuntos
Neoplasias Colorretais/genética , Receptores de IgG/genética , Idoso , Alanina/análogos & derivados , Alanina/uso terapêutico , Antineoplásicos/uso terapêutico , Cetuximab/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Análise de Sobrevida , Triazinas/uso terapêutico
6.
Can J Public Health ; 109(4): 464-472, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30225576

RESUMO

OBJECTIVE: Previous studies considered the role of occupational causes in kidney cancer but were limited by small sample sizes and imprecise exposure assessment. This study examined the relationship between occupational exposure to asbestos and the risk of kidney cancer across a range of jobs in a large, population-based case-control study in Canada. METHODS: Data were from the case-control component of the National Enhanced Cancer Surveillance System, a study conducted between 1994 and 1997 in eight Canadian provinces. Male kidney cancer cases, histologically confirmed, and controls completed questionnaires on socio-demographics, anthropometry, diet, smoking, secondhand smoke exposure, and physical activity. Occupational histories were also collected, including each job held for at least 1 year since the age of 18. Occupational hygienists, blinded to case status, assigned exposure to asbestos, considering intensity, frequency, and probability of exposure (each 3-point scales). Logistic regression was used to estimate the odds of kidney cancer in exposed participants (defined using three metrics) compared to those without asbestos exposure. RESULTS: There were 712 cases and 2454 controls in these analyses. Ever-exposure to asbestos was associated with 20% increased odds of kidney cancer compared to unexposed workers (OR 1.2, 95% confidence interval 1.0-1.4 when including possibly exposed workers). A small increase in risk was observed with cumulative exposure, while increasing intensity of exposure was related to increased odds of kidney cancer. CONCLUSIONS: This study found some evidence for an association between occupational exposure to asbestos and kidney cancer. Higher intensity of exposure to asbestos had the strongest relationship with kidney cancer risk.


Assuntos
Asbestos/toxicidade , Neoplasias Renais/induzido quimicamente , Doenças Profissionais/induzido quimicamente , Exposição Ocupacional/efeitos adversos , Canadá/epidemiologia , Estudos de Casos e Controles , Humanos , Neoplasias Renais/epidemiologia , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/epidemiologia , Exposição Ocupacional/estatística & dados numéricos , Fatores de Risco
7.
Ann Work Expo Health ; 62(8): 978-989, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30059990

RESUMO

Introduction: Kidney cancer is the fifth most common incident cancer in Canadian men. Diesel and gasoline exhausts are common workplace exposures that have been examined as risk factors for non-lung cancer sites, including the kidney, but limitations in exposure assessment methods have contributed to inconsistent findings. The objective of this study was to assess the relationship between occupational gasoline and diesel engine exhausts and the risk of kidney cancer in men. Methods: The National Enhanced Cancer Surveillance System (NECSS) is a Canadian population-based case-control study conducted in 1994-1997. Incident kidney cancer cases were identified using provincial registries, while the control series was identified through random-digit dialing, or provincial administrative databases. Self-reported questionnaires were used to obtain information on lifetime occupational history and cancer risk factors. Two hygienists, blinded to case status, coded occupational histories for diesel and gasoline exhaust exposures using concentration, frequency, duration, and reliability. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) separately by exhaust type. The separate and combined impacts of both engine exhausts were also examined. ORs were adjusted for age, province, body mass index, occupational secondhand smoke exposure, and education. Results: Of the kidney cancer cases (n = 712), 372 (52%) had exposure to both exhausts at some point, and 984 (40%) of the controls (n = 2457) were ever exposed. Workers who had ever been exposed to engine exhausts were more likely to have kidney cancer than those who were never exposed (OR diesel = 1.23, 95% CI = 0.99-1.53; OR gasoline = 1.51, 95% CI = 1.23-1.86). Exposure to gasoline exhaust was consistently associated with kidney cancer in a dose-response manner (P value for trends in highest attained and cumulative exposure both <0.0001). Those men with high cumulative exposure to both gasoline and diesel exhaust had a 76% increased odds of kidney cancer (95% CI = 1.27-2.43). Conclusions: This study provides evidence that occupational gasoline, and to a lesser extent, diesel exhaust exposure may increase the risk of kidney cancer.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Neoplasias Renais/epidemiologia , Doenças Profissionais/epidemiologia , Exposição Ocupacional/análise , Emissões de Veículos/análise , Adulto , Canadá/epidemiologia , Estudos de Casos e Controles , Gasolina , Humanos , Incidência , Neoplasias Renais/etiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/etiologia , Exposição Ocupacional/efeitos adversos , Razão de Chances , Reprodutibilidade dos Testes , Fatores de Risco , Inquéritos e Questionários
9.
Cancer Epidemiol Biomarkers Prev ; 25(12): 1537-1549, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27566420

RESUMO

Lung cancer remains the leading cause of cancer mortality worldwide. Known histomolecular characteristics and genomic profiles provide limited insight into factors influencing patient outcomes. Telomere length (TL) is important for genomic integrity and has been a growing area of interest as agents targeting telomerase are being evaluated. Chromosome 5p15.33, an established cancer susceptibility locus, contains a telomerase-regulatory gene, TERT, and CLPTM1L, a gene associated with cisplatin-induced apoptosis. This review offers a summary of the clinical utility of 5p15.33 polymorphisms and TL. A total of 621 abstracts were screened, and 14 studies (7 for 5p15.33, 7 for TL) were reviewed. Endpoints included overall survival (OS), progression-free survival (PFS), therapy response, and toxicity. Of the 23 genetic variants identified, significant associations with OS and/or PFS were reported for rs401681 (CLPTM1L), rs4975616 (TERT-CLPTM1L), and rs2736109 (TERT). Both shorter and longer TL, in tumor and blood, was linked to OS and PFS. Overall, consistent evidence across multiple studies of 5p15.33 polymorphisms and TL was lacking. Despite the potential to become useful prognostic biomarkers in lung cancer, the limited number of reports and their methodologic limitations highlight the need for larger, carefully designed studies with clinically defined subpopulations and higher resolution genetic analyses. Cancer Epidemiol Biomarkers Prev; 25(12); 1537-49. ©2016 AACR.


Assuntos
Cromossomos Humanos Par 5 , Neoplasias Pulmonares/genética , Polimorfismo de Nucleotídeo Único , Homeostase do Telômero , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Proteínas de Membrana/genética , Proteínas de Neoplasias/genética , Prognóstico , Telomerase/genética
10.
Cancer Epidemiol Biomarkers Prev ; 25(2): 374-80, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26656293

RESUMO

BACKGROUND: Telomeres protect from DNA degradation and maintain chromosomal stability. Short telomeres have been associated with an increased risk of cancer at several sites. However, there is limited knowledge about the lifestyle determinants of telomere length. We aimed to determine the effect of three factors, known to be important in cancer etiology, on relative leukocyte telomere length (rLTL): alcohol consumption, smoking, and physical activity. METHODS: This cross-sectional study included 477 healthy volunteers ages 20 to 50 years who completed a questionnaire and provided a fasting blood sample. Multiplex quantitative real-time PCR (qPCR) was used to measure rLTL. Regression coefficients were calculated using multiple linear regression while controlling for important covariates. RESULTS: There was no association between alcohol consumption and rLTL. Daily smokers and those in the middle and lower tertile of pack-years smoking had shorter rLTL than never daily smokers (P = 0.02). Data were suggestive of a linear trend with total physical activity (P = 0.06). Compared with the lowest quartile, the highest quartile of vigorous physical activity was associated with longer rLTL. A significant linear trend of increasing rLTL with increasing vigorous physical activity was observed (P = 0.02). CONCLUSIONS: Cigarette smoking and vigorous physical activity have an impact on telomere length. Smoking was related to shorter telomere length while vigorous physical activity was related to longer telomeres. IMPACT: The findings from this study suggest that lifestyle may play an important role in telomere dynamics and also suggest that engaging in healthy behaviors may mitigate the effect of harmful behaviors on telomere length.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Leucócitos/metabolismo , Atividade Motora/fisiologia , Fumar/efeitos adversos , Adulto , Estudos Transversais , Humanos , Leucócitos/citologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Encurtamento do Telômero , Adulto Jovem
11.
Cancer Med ; 4(12): 1948-62, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26511593

RESUMO

The International Agency for Research on Cancer has classified diesel exhaust as a carcinogen based on lung cancer evidence; however, few studies have investigated the effect of engine emissions on bladder cancer. The purpose of this study was to investigate the association between occupational exposure to diesel and gasoline emissions and bladder cancer in men using data from the Canadian National Enhanced Cancer Surveillance System; a population-based case-control study. This analysis included 658 bladder cancer cases and 1360 controls with information on lifetime occupational histories and a large number of possible cancer risk factors. A job-exposure matrix for engine emissions was supplemented by expert review to assign values for each job across three dimensions of exposure: concentration, frequency, and reliability. Odds ratios (OR) and their corresponding 95% confidence intervals were estimated using logistic regression. Relative to unexposed, men ever exposed to high concentrations of diesel emissions were at an increased risk of bladder cancer (OR = 1.64, 0.87-3.08), but this result was not significant, and those with >10 years of exposure to diesel emissions at high concentrations had a greater than twofold increase in risk (OR = 2.45, 1.04-5.74). Increased risk of bladder cancer was also observed with >30% of work time exposed to gasoline engine emissions (OR = 1.59, 1.04-2.43) relative to the unexposed, but only among men that had never been exposed to diesel emissions. Taken together, our findings support the hypothesis that exposure to high concentrations of diesel engine emissions may increase the risk of bladder cancer.


Assuntos
Gasolina/efeitos adversos , Exposição Ocupacional/efeitos adversos , Neoplasias da Bexiga Urinária/epidemiologia , Neoplasias da Bexiga Urinária/etiologia , Emissões de Veículos/toxicidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Canadá/epidemiologia , Estudos de Casos e Controles , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Razão de Chances , Vigilância da População , Fatores de Risco
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