Cancer and environment: definitions and misconceptions.

BACKGROUND: Scientific evidence supports an association between environmental exposures and cancer. However, a reliable estimate for the proportion of cancers attributable to environmental factors is currently unavailable. This may be related to the varying definitions of the term "environment." The current review aims to determine how the reporting of the definition of the environment and of the estimates of environmentally attributable risks have changed over the past 50 years. METHODS: A systematic literature search was performed to retrieve all relevant publications relating to the environment and cancer from January 1960 to December 2010 using PubMed, EMBASE, Scopus, and Web of Science. Definitions of the environment and environmentally attributable risks for cancer were extracted from each relevant publication. RESULTS: The search resulted in 261 relevant publications. We found vast discrepancies in the definition of the environment, ranging from broad (including lifestyle factors, occupational exposures, pollutants, and other non-genetic factors) to narrow (including air, water, and soil pollutants). Reported environmentally attributable risk estimates ranged from 1% to 100%. CONCLUSIONS: Our findings emphasize the discrepancies in reporting environmental causation of cancer and the limits of inference in interpreting environmentally attributable risk estimates. Rather than achieving consensus on a single definition for the environment, we suggest the focus be on achieving transparency for any environmentally attributable risks.

Applying the Strategic Planning Process to a Large Research Consortium: The Example of the National Cancer Institute Cohort Consortium.

Strategic planning is conducted by many organizations to systematically evaluate and assess their current state, establish or update their mission and/or goals, and identify strategies and activities to achieve the goals. The National Cancer Institute (NCI) Cohort Consortium is a collaborative network of 62 prospective cohort studies and their affiliated investigators that focus on cancer etiology and outcome research. The organization's membership grew markedly from 10 cohort studies at its inception in 2001 to 59 cohort studies at the time of the launch of the Consortium's strategic planning in 2017. This paper describes the strategic planning process that was conducted to establish organizational goals and to develop strategies and activities consistent with the Consortium's mission. The process involved a 2-year iterative approach combining surveys and in-person meetings. The resulting goals focus on communication, career development, research facilitation, scientific gaps, and common scientific challenges. The NCI Cohort Consortium's strategic plan and evaluation of its progress will advance new initiatives in cancer etiology and survivorship research.

Circulating 25-hydroxyvitamin D and risk of pancreatic cancer: Cohort Consortium Vitamin D Pooling Project of Rarer Cancers.

Results from epidemiologic studies examining pancreatic cancer risk and vitamin D intake or 25-hydroxyvitamin D (25(OH)D) concentrations (the best indicator of vitamin D derived from diet and sun) have been inconsistent. Therefore, the authors conducted a pooled nested case-control study of participants from 8 cohorts within the Cohort Consortium Vitamin D Pooling Project of Rarer Cancers (VDPP) (1974-2006) to evaluate whether prediagnostic circulating 25(OH)D concentrations were associated with the development of pancreatic cancer. In total, 952 incident pancreatic adenocarcinoma cases occurred among participants (median follow-up, 6.5 years). Controls (n = 1,333) were matched to each case by cohort, age, sex, race/ethnicity, date of blood draw, and follow-up time. Conditional logistic regression analysis was used to calculate smoking-, body mass index-, and diabetes-adjusted odds ratios and 95% confidence intervals for pancreatic cancer. Clinically relevant 25(OH)D cutpoints were compared with a referent category of 50-<75 nmol/L. No significant associations were observed for participants with lower 25(OH)D status. However, a high 25(OH)D concentration (> or =100 nmol/L) was associated with a statistically significant 2-fold increase in pancreatic cancer risk overall (odds ratio = 2.12, 95% confidence interval: 1.23, 3.64). Given this result, recommendations to increase vitamin D concentrations in healthy persons for the prevention of cancer should be carefully considered.

Circulating 25-hydroxyvitamin D and risk of epithelial ovarian cancer: Cohort Consortium Vitamin D Pooling Project of Rarer Cancers.

A role for vitamin D in ovarian cancer etiology is supported by ecologic studies of sunlight exposure, experimental mechanism studies, and some studies of dietary vitamin D intake and genetic polymorphisms in the vitamin D receptor. However, few studies have examined the association of circulating 25-hydroxyvitamin D (25(OH)D), an integrated measure of vitamin D status, with ovarian cancer risk. A nested case-control study was conducted among 7 prospective studies to evaluate the circulating 25(OH)D concentration in relation to epithelial ovarian cancer risk. Logistic regression models were used to estimate odds ratios and 95% confidence intervals among 516 cases and 770 matched controls. Compared with 25(OH)D concentrations of 50-<75 nmol/L, no statistically significant associations were observed for <37.5 (odds ratio (OR) = 1.21, 95% confidence interval (CI): 0.87, 1.70), 37.5-<50 (OR = 1.03, 95% CI: 0.75, 1.41), or > or =75 (OR = 1.11, 95% CI: 0.79, 1.55) nmol/L. Analyses stratified by tumor subtype, age, body mass index, and other variables were generally null but suggested an inverse association between 25(OH)D and ovarian cancer risk among women with a body mass index of > or =25 kg/m(2) (P(interaction) < 0.01). In conclusion, this large pooled analysis did not support an overall association between circulating 25(OH)D and ovarian cancer risk, except possibly among overweight women.

Circulating 25-hydroxyvitamin D and the risk of rarer cancers: Design and methods of the Cohort Consortium Vitamin D Pooling Project of Rarer Cancers.

The Cohort Consortium Vitamin D Pooling Project of Rarer Cancers (VDPP), a consortium of 10 prospective cohort studies from the United States, Finland, and China, was formed to examine the associations between circulating 25-hydroxyvitamin D (25(OH)D) concentrations and the risk of rarer cancers. Cases (total n = 5,491) included incident primary endometrial (n = 830), kidney (n = 775), ovarian (n = 516), pancreatic (n = 952), and upper gastrointestinal tract (n = 1,065) cancers and non-Hodgkin lymphoma (n = 1,353) diagnosed in the participating cohorts. At least 1 control was matched to each case on age, date of blood collection (1974-2006), sex, and race/ethnicity (n = 6,714). Covariate data were obtained from each cohort in a standardized manner. The majority of the serum or plasma samples were assayed in a central laboratory using a direct, competitive chemiluminescence immunoassay on the DiaSorin LIAISON platform (DiaSorin, Inc., Stillwater, Minnesota). Masked quality control samples included serum standards from the US National Institute of Standards and Technology. Conditional logistic regression analyses were conducted using clinically defined cutpoints, with 50-<75 nmol/L as the reference category. Meta-analyses were also conducted using inverse-variance weights in random-effects models. This consortium approach permits estimation of the association between 25(OH)D and several rarer cancers with high accuracy and precision across a wide range of 25(OH)D concentrations.

Correlates of circulating 25-hydroxyvitamin D: Cohort Consortium Vitamin D Pooling Project of Rarer Cancers.

Low vitamin D status is common globally and is associated with multiple disease outcomes. Understanding the correlates of vitamin D status will help guide clinical practice, research, and interpretation of studies. Correlates of circulating 25-hydroxyvitamin D (25(OH)D) concentrations measured in a single laboratory were examined in 4,723 cancer-free men and women from 10 cohorts participating in the Cohort Consortium Vitamin D Pooling Project of Rarer Cancers, which covers a worldwide geographic area. Demographic and lifestyle characteristics were examined in relation to 25(OH)D using stepwise linear regression and polytomous logistic regression. The prevalence of 25(OH)D concentrations less than 25 nmol/L ranged from 3% to 36% across cohorts, and the prevalence of 25(OH)D concentrations less than 50 nmol/L ranged from 29% to 82%. Seasonal differences in circulating 25(OH)D were most marked among whites from northern latitudes. Statistically significant positive correlates of 25(OH)D included male sex, summer blood draw, vigorous physical activity, vitamin D intake, fish intake, multivitamin use, and calcium supplement use. Significant inverse correlates were body mass index, winter and spring blood draw, history of diabetes, sedentary behavior, smoking, and black race/ethnicity. Correlates varied somewhat within season, race/ethnicity, and sex. These findings help identify persons at risk for low vitamin D status for both clinical and research purposes.

The National Cancer Institute Cohort Consortium: An International Pooling Collaboration of 58 Cohorts from 20 Countries.

Cohort studies have been central to the establishment of the known causes of cancer. To dissect cancer etiology in more detail-for instance, for personalized risk prediction and prevention, assessment of risks of subtypes of cancer, and assessment of small elevations in risk-there is a need for analyses of far larger cohort datasets than available in individual existing studies. To address these challenges, the NCI Cohort Consortium was founded in 2001. It brings together 58 cancer epidemiology cohorts from 20 countries to undertake large-scale pooling research. The cohorts in aggregate include over nine million study participants, with biospecimens available for about two million of these. Research in the Consortium is undertaken by >40 working groups focused on specific cancer sites, exposures, or other research areas. More than 180 publications have resulted from the Consortium, mainly on genetic and other cancer epidemiology, with high citation rates. This article describes the foundation of the Consortium; its structure, governance, and methods of working; the participating cohorts; publications; and opportunities. The Consortium welcomes new members with cancer-oriented cohorts of 10,000 or more participants and an interest in collaborative research. Cancer Epidemiol Biomarkers Prev; 27(11); 1307-19. ©2018 AACR.

The Cancer Epidemiology Descriptive Cohort Database: A Tool to Support Population-Based Interdisciplinary Research.

BACKGROUND: We report on the establishment of a web-based Cancer Epidemiology Descriptive Cohort Database (CEDCD). The CEDCD's goals are to enhance awareness of resources, facilitate interdisciplinary research collaborations, and support existing cohorts for the study of cancer-related outcomes. METHODS: Comprehensive descriptive data were collected from large cohorts established to study cancer as primary outcome using a newly developed questionnaire. These included an inventory of baseline and follow-up data, biospecimens, genomics, policies, and protocols. Additional descriptive data extracted from publicly available sources were also collected. This information was entered in a searchable and publicly accessible database. We summarized the descriptive data across cohorts and reported the characteristics of this resource. RESULTS: As of December 2015, the CEDCD includes data from 46 cohorts representing more than 6.5 million individuals (29% ethnic/racial minorities). Overall, 78% of the cohorts have collected blood at least once, 57% at multiple time points, and 46% collected tissue samples. Genotyping has been performed by 67% of the cohorts, while 46% have performed whole-genome or exome sequencing in subsets of enrolled individuals. Information on medical conditions other than cancer has been collected in more than 50% of the cohorts. More than 600,000 incident cancer cases and more than 40,000 prevalent cases are reported, with 24 cancer sites represented. CONCLUSIONS: The CEDCD assembles detailed descriptive information on a large number of cancer cohorts in a searchable database. IMPACT: Information from the CEDCD may assist the interdisciplinary research community by facilitating identification of well-established population resources and large-scale collaborative and integrative research. Cancer Epidemiol Biomarkers Prev; 25(10); 1392-401. ©2016 AACR.

Multiple Myeloma Mortality in Relation to Obesity Among African Americans.

Multiple myeloma (MM) incidence and mortality are higher among African Americans (AAs) than among other population groups. The prevalence of obesity is also elevated among AAs, but few studies have examined risk of this cancer in relation to body size among AAs. We combined data from seven prospective cohorts tracking mortality among 239 597 AA adults and used Cox proportional hazards regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for death because of MM according to body mass index (BMI) at cohort entry, adjusted for age (as time-scale) and sex. Relative to those with normal BMIs (18.5-25 kg/m(2)), mortality increased monotonically as BMI increased, with hazard ratios reaching 1.43 (95% CI = 1.03 to 1.97) for BMIs of 35 kg/m(2) or greater. The findings suggest that obesity is a risk factor for MM and a contributor to the elevated rates and rising incidence trends of MM among AAs in the United States.

A pooled analysis of body mass index and mortality among African Americans.

Pooled analyses among whites and East Asians have demonstrated positive associations between all-cause mortality and body mass index (BMI), but studies of African Americans have yielded less consistent results. We examined the association between BMI and all-cause mortality in a sample of African Americans pooled from seven prospective cohort studies: NIH-AARP, 1995-2009; Adventist Health Study 2, 2002-2008; Black Women's Health Study, 1995-2009; Cancer Prevention Study II, 1982-2008; Multiethnic Cohort Study, 1993-2007; Prostate, Lung, Colorectal and Ovarian Screening Trial, 1993-2009; Southern Community Cohort Study, 2002-2009. 239,526 African Americans (including 100,175 never smokers without baseline heart disease, stroke, or cancer), age 30-104 (mean 52) and 71% female, were followed up to 26.5 years (mean 11.7). Hazard ratios (HR) and 95% confidence intervals (CI) for mortality were derived from multivariate Cox proportional hazards models. Among healthy, never smokers (11,386 deaths), HRs (CI) for BMI 25-27.4, 27.5-29.9, 30-34.9, 35-39.9, 40-49.9, and 50-60 kg/m(2) were 1.02 (0.92-1.12), 1.06 (0.95-1.18), 1.32 (1.18-1.47), 1.54 (1.29-1.83), 1.93 (1.46-2.56), and 1.93 (0.80-4.69), respectively among men and 1.06 (0.99-1.15), 1.15 (1.06-1.25), 1.24 (1.15-1.34), 1.58 (1.43-1.74), 1.80 (1.60-2.02), and 2.31 (1.74-3.07) respectively among women (reference category 22.5-24.9). HRs were highest among those with the highest educational attainment, longest follow-up, and for cardiovascular disease mortality. Obesity was associated with a higher risk of mortality in African Americans, similar to that observed in pooled analyses of whites and East Asians. This study provides compelling evidence to support public health efforts to prevent excess weight gain and obesity in African Americans.

A pooled analysis of body mass index and pancreatic cancer mortality in african americans.

BACKGROUND: Pancreatic cancer is a leading cause of cancer-related mortality in the United States and both incidence and mortality are highest in African Americans. Obesity is also disproportionately high in African Americans, but limited data are available on the relation of obesity to pancreatic cancer in this population. METHODS: Seven large prospective cohort studies pooled data from African American participants. Body mass index (BMI) was calculated from self-reported height and weight at baseline. Cox regression was used to calculate HRs and 95% confidence intervals (CI) for levels of BMI relative to BMI 18.5-24.9, with adjustment for covariates. Primary analyses were restricted to participants with ≥5 years of follow-up because weight loss before diagnosis may have influenced baseline BMI in cases who died during early follow-up. RESULTS: In follow-up of 239,597 participants, 897 pancreatic cancer deaths occurred. HRs were 1.08 (95% CI, 0.90-1.31) for BMI 25.0 to 29.9, 1.25 (95% CI, 0.99-1.57) for BMI 30.0 to 34.9, and 1.31 (95% CI, 0.97-1.77) for BMI ≥35.0 among those with ≥5 years of follow-up (Ptrend = 0.03). The association was evident among both sexes and was independent of a history of diabetes. A stronger association was observed among never-smokers (BMI ≥30 vs. referent: HR = 1.44; 95% CI, 1.02-2.03) than among smokers (HR = 1.16; 95% CI, 0.87-1.54; Pinteraction = 0.02). CONCLUSION: The findings suggest that obesity is independently associated with increased pancreatic cancer mortality in African Americans. IMPACT: Interventions to reduce obesity may also reduce risk of pancreatic cancer mortality, particularly among never-smokers.

Frontiers in cancer epidemiology: a challenge to the research community from the Epidemiology and Genomics Research Program at the National Cancer Institute.

The Epidemiology and Genomics Research Program (EGRP) at the National Cancer Institute (NCI) is developing scientific priorities for cancer epidemiology research in the next decade. We would like to engage the research community and other stakeholders in a planning effort that will include a workshop in December 2012 to help shape new foci for cancer epidemiology research. To facilitate the process of defining the future of cancer epidemiology, we invite the research community to join in an ongoing web-based conversation at http://blog-epi.grants.cancer.gov/ to develop priorities and the next generation of high-impact studies.

Educational needs assessment for pediatric health care providers on pesticide toxicity.

PURPOSE: This pilot project, carried out under the National Strategies for Health Care Providers: Pesticides Initiative, assessed the attitudes, beliefs and practices of pediatricians, nurse practitioners, physicians assistants, and nurses in the metropolitan Washington, D.C., area and the surrounding rural counties regarding health effects of pesticide toxicity and continuing education on pesticide toxicity in the years 2001-2002. METHODS: Data were collected from practitioners (physicians, physician assistants, and nurse practitioners) and nurses using questionnaires as well as from practitioners using focus groups. Sites for questionnaire distribution and focus groups were selected to represent a variety of practice types and geographic settings. One-hundred-sixty questionnaires from practitioners and 43 from nurses were analyzed. These issues were probed further in six focus groups with 29 participants. RESULTS: Most respondents in both groups did not frequently diagnose or ask questions about pesticide toxicity on patient histories. Most focus group participants were more comfortable answering questions about acute pesticide toxicity, and many relied on poison control centers for assistance with management of acute cases. They expressed less understanding and more uncertainties about chronic toxicity. When asked questions by patients, 64% of practitioners and 69% of nurses felt poorly prepared to answer them. Forty percent of practitioners but only 26% of nurses felt it was important to obtain more information on pesticides. There were divergent preferences on ways to obtain continuing medical education (CME) in general, but a recurrent theme was the need to make CME on pesticide toxicity clinically relevant and one topic among several in a CME conference. Lectures and short courses were the most commonly preferred modes of education among both practitioners and nurses. CONCLUSION: Educational materials to reach this population of pediatric clinicians on pesticides, as well as other environmental health topics, should make the case justifying the importance of the topics, highlight information of clinical relevance, and use a variety of media. These results should be confirmed before being generalized to a broader group of clinicians, although the consistency of findings between focus groups suggests they are robust, at least for this geographic area.