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On November 9 and 10, 2015, the International Conference on Mesothelioma in Populations Exposed to Naturally Occurring Asbestiform Fibers was held at the University of Hawaii Cancer Center in Honolulu, Hawaii. The meeting was cosponsored by the International Association for the Study of Lung Cancer, and the agenda was designed with significant input from staff at the U.S. National Cancer Institute and National Institute of Environmental Health Sciences. A multidisciplinary group of participants presented updates reflecting a range of disciplinary perspectives, including mineralogy, geology, epidemiology, toxicology, biochemistry, molecular biology, genetics, public health, and clinical oncology. The group identified knowledge gaps that are barriers to preventing and treating malignant mesothelioma (MM) and the required next steps to address barriers. This manuscript reports the group’s efforts and focus on strategies to limit risk to the population and reduce the incidence of MM. Four main topics were explored: genetic risk, environmental exposure, biomarkers, and clinical interventions. Genetics plays a critical role in MM when the disease occurs in carriers of germline BRCA1 associated protein 1 mutations. Moreover, it appears likely that, in addition to BRCA1 associated protein 1, other yet unknown genetic variants may also influence the individual risk for development of MM, especially after exposure to asbestos and related mineral fibers. MM is an almost entirely preventable malignancy as it is most often caused by exposure to commercial asbestos or mineral fibers with asbestos-like health effects, such as erionite. In the past in North America and in Europe, the most prominent source of exposure was related to occupation. Present regulations have reduced occupational exposure in these countries; however, some people continue to be exposed to previously installed asbestos in older construction and other settings. Moreover, an increasing number of people are being exposed in rural areas that contain noncommercial asbestos, erionite, and other mineral fibers in soil or rock (termed naturally occurring asbestos[NOA]) and are being developed. Public health authorities, scientists, residents, and other affected groups must work together in the areas where exposure to asbestos, including NOA, has been documented in the environment to mitigate or reduce this exposure. Although a blood biomarker validated to be effective for use in screening and identifying MM at an early stage in asbestos/NOA-exposed populations is not currently available, novel biomarkers presented at the meeting, such as high mobility group box 1 and fibulin-3, are promising. There was general agreement that current treatment for MM, which is based on surgery and standard chemotherapy, has a modest effect on the overall survival (OS), which remains dismal. Additionally, although much needed novel therapeutic approaches for MM are being developed and explored in clinical trials, there is a critical need to invest in prevention research, in which there is a great opportunity to reduce the incidence and mortality from MM.

Questions remain about the effectiveness, dose, and timing of folic acid in preventing orofacial clefts. Case-control studies report conflicting results. There have been no cohort studies of orofacial clefts and the use of folic acid without other vitamins.

Objective: We examined the relation between whole grains, fruit, vegetables and dietary fiber and colon cancer risk in the prospective Cancer Prevention Study II Nutrition Cohort. Methods: In 1992–1993, 62,609 men and 70,554 women completed questionnaires on medical history, diet and lifestyle behaviors. After exclusions, we confirmed 298 cases of incident colon cancer among men and 210 among women through August 31, 1997. Results: Multivariate rate ratios (RR) and 95% confidence intervals (CI) for all dietary factors were null. However, a statistically non-significant 30% reduction in risk was observed for men with the highest vegetable intakes (RR = 0.69, CI = 0.47–1.03, top versus. bottom quintile, ptrend = 0.10). Men with very low (lowest tertile within the lowest quintile) intakes of vegetables and dietary fiber were at increased risk compared to those in the highest four quintiles of intake (vegetables RR = 1.79, CI = 1.22–2.61, ptrend = 0.04, and fiber RR = 1.96, CI = 1.24–3.10, ptrend = 0.006). Women with very low intakes of fruit were also at increased risk (RR = 1.86, CI =1.18–2.94, ptrend = 0.06). Conclusions: Higher intakes of plant foods or fiber were not related to lower risk of colon cancer. However, our data suggest that very low intakes of plant foods may increase risk, and that certain phytochemical subgroups may decrease risk.

Objective: Calcium, vitamin D, and dairy product intake may reduce the risk of colorectal cancer. We therefore examined the association between these factors and risk of colorectal cancer in a large prospective cohort of United States men and women. Methods: Participants in the Cancer Prevention Study II Nutrition Cohort completed a detailed questionnaire on diet, medical history, and lifestyle in 1992–93. After excluding participants with a history of cancer or incomplete dietary information, 60,866 men and 66,883 women remained for analysis. During follow-up through 31 August 1997 we documented 421 and 262 cases of incident colorectal cancers among men and women, respectively. Multivariate-adjusted rate ratios (RR) were calculated using Cox proportional hazards models. Results: Total calcium intake (from diet and supplements) was associated with marginally lower colorectal cancer risk in men and women (RR = 0.87, 95% CI 0.67–1.12, highest vslowest quintiles, ptrend = 0.02). The association was strongest for calcium from supplements (RR = 0.69, 95% CI 0.49–0.96 for ≥500 mg/day vsnone). Total vitamin D intake (from diet and multivitamins) was also inversely associated with risk of colorectal cancer, particularly among men (RR = 0.71, 95% CI 0.51–0.98, ptrend = 0.02). Dairy product intake was not related to overall risk. Conclusions: Our results support the hypothesis that calcium modestly reduces risk of colorectal cancer. Vitamin D was associated with reduced risk of colorectal cancer only in men.

Linxian, China, is a region with high incidence of esophageal cancer and a history of poor nutritional status. Nutrition Intervention Trials were conducted in this area from 1985 through 1991 and found a reduction in total cancer mortality in the group receiving supplementation of beta-carotene/selenium/alpha-tocopherol. The positive results of those trials have, in part, been ascribed to the poor nutritional status of this population. To investigate more recent food patterns, nutrient intakes, and seasonal variations in the diet, dietary surveys were conducted among the residents of Linxian in 1996. Food consumption data were collected among 104 households in spring and 106 households in autumn using a method of food inventory changes. Intake of nutrients was estimated and compared to the Chinese Recommended Dietary Allowance (RDA). In both seasons, the five most common food groups consumed were cereals, fresh vegetables, yams, seasonings, and eggs. Low nutrient intakes were found for selenium (79% RDA and 66% RDA), zinc (72% RDA and 62% RDA), vitamin B2(64% RDA and 52% RDA), and calcium (53% RDA and 39% RDA) in both spring and autumn. A large seasonal variation was seen in the consumption of leafy vegetables, root vegetables and eggs, all of which might have contributed to the lower intake of vitamin A (25% RDA), vitamin C (75% RDA), protein (76% RDA), and vitamin E (78% RDA) in autumn. These indicate that the nutrient intake in Linxian is inadequate for a number of vitamins and minerals including those shown to be associated with esophageal cancer.

Cigarette smoking is associated with increased risk of stomach cancer in many studies but there are limited data on this relationship in women and on risk associated with use of tobacco products other than cigarettes. We examined stomach cancer death rates in relation to cigarette smoking in women and use of cigarette, cigar, pipe, or smokeless tobacco in men in a nationwide prospective mortality study in the United States (US). Cohort follow-up from 1982–96 identified 996 and 509 stomach cancer deaths among 467,788 men and 588,053 women, respectively. Cox proportional hazards models were fitted to estimate rate ratios (RR) and 95% confidence intervals (CI) using non-users of tobacco as the referent group. Multivariate-adjusted RRs were the highest for men who currently smoked cigars (RR = 2.29, 95% CI = 1.49–3.51) or cigarettes (RR = 2.16, 95% CI = 1.75–2.67) and both increased with smoking duration. Women who currently (RR = 1.49, 95% CI = 1.18–1.88) or formerly (RR = 1.36, 95% CI = 1.08–1.71) smoked cigarettes were at significantly increased risk, as were men who formerly smoked cigarettes (RR = 1.55, 95% CI = 1.28–1.88), or currently (RR = 1.81, 95% CI = 1.40–2.35) or formerly (RR: 1.57, 95% CI = 1.22–2.03) used more than one type of tobacco. Men who reported a history of chronic indigestion or gastroduodenal ulcer had substantially higher mortality rates associated with current cigarette (RR = 3.45, 95% CI = 2.05–5.80) or cigar (RR = 8.93, 95% CI = 4.02–19.90) smoking, as did men who were current aspirin users. If causal, the estimated proportion of stomach cancer deaths attributable to tobacco use would be 28% in US men and 14% in women. We conclude that prolonged use of tobacco products is associated with increased stomach cancer mortality in men and women. The accumulated evidence from this and other studies support reconsidering stomach cancer as a tobacco-related cancer. © 2002 Wiley-Liss, Inc.

Large-scale, prospective cohort studies have played a critical role in discovering factors that contribute to variability in cancer risk in human populations. Epidemiologists and volunteers at the American Cancer Society (ACS) were among the first to establish such cohorts, beginning in the early 1950s and continuing through the present, and these ACS cohorts have made landmark contributions in many areas of epidemiologic research. The Cancer Prevention Study II Nutrition Cohort was established in 1992 and was designed to investigate the relation between diet and other lifestyle factors and exposures and the risk of cancer, mortality, and survival. The cohort includes over 84,000 men and 97,000 women who completed a mailed questionnaire in 1992. New questionnaires are sent to surviving cohort members every other year to update exposure information and to ascertain new occurrences of cancer; a 90% response rate was achieved for follow-up questionnaires in 1997 and 1999. Reported cancers are verified through medical records, registry linkage, or death certificates. The cohort is followed actively for all cases of incident cancer and for all causes of death. Through a collaborative effort among ACS national and division staff, volunteers, and the American College of Surgeons, blood samples were collected from a subgroup of 40,000 cohort members and are in storage at a central repository for future investigation of dietary, hormonal, genetic, and other factors and cancer risk. Collection of DNA samples from buccal cells in an additional 50,000 cohort members is underway currently and will be completed in 2002. This new cohort of both men and women promises to be particularly valuable for the study of cancer occurrence, mortality, and survival as they relate to obesity and weight change, physical activity at various points in life, vitamin supplement use, exogenous hormone use, other medications (such as aspirin and nonsteroidal anti- inflammatory drugs) and cancer screening modalities. Cancer 2002;94:2490–2501. © 2002 American Cancer Society. DOI 10.1002/cncr.101970

Large-scale, prospective cohort studies have played a critical role in discovering factors that contribute to variability in cancer risk in human populations. Epidemiologists and volunteers at the American Cancer Society (ACS) were among the first to establish such cohorts, beginning in the early 1950s and continuing through the present, and these ACS cohorts have made landmark contributions in many areas of epidemiologic research. The Cancer Prevention Study II Nutrition Cohort was established in 1992 and was designed to investigate the relation between diet and other lifestyle factors and exposures and the risk of cancer, mortality, and survival. The cohort includes over 84,000 men and 97,000 women who completed a mailed questionnaire in 1992. New questionnaires are sent to surviving cohort members every other year to update exposure information and to ascertain new occurrences of cancer; a 90% response rate was achieved for follow-up questionnaires in 1997 and 1999. Reported cancers are verified through medical records, registry linkage, or death certificates. The cohort is followed actively for all cases of incident cancer and for all causes of death. Through a collaborative effort among ACS national and division staff, volunteers, and the American College of Surgeons, blood samples were collected from a subgroup of 40,000 cohort members and are in storage at a central repository for future investigation of dietary, hormonal, genetic, and other factors and cancer risk. Collection of DNA samples from buccal cells in an additional 50,000 cohort members is underway currently and will be completed in 2002. This new cohort of both men and women promises to be particularly valuable for the study of cancer occurrence, mortality, and survival as they relate to obesity and weight change, physical activity at various points in life, vitamin supplement use, exogenous hormone use, other medications (such as aspirin and nonsteroidal anti-inflammatory drugs) and cancer screening modalities. Cancer 2002;94:500–11. © 2002 American Cancer Society.

Objective:Multivitamins contain several nutrients, including folic acid, which are hypothesized to reduce colon cancer risk. Previous epidemiologic studies have suggested that effects of multivitamins containing substantial amounts of folic acid (introduced in 1973) may not be evident until 15 or more years since first use. Methods:We examined the association between daily multivitamin use and colon cancer mortality among 806,397 US men and women in the Cancer Prevention Study II cohort who completed a questionnaire at enrollment in 1982 and were followed for mortality through 1998. Results:After multivariate adjustment, multivitamin use at enrollment showed little association with colon cancer mortality. After 15 years since first use of a multivitamin potentially containing folic acid, we observed slightly decreased risk of colon cancer mortality (rate ratio (RR) = 0.89, 95% confidence interval (CI) 0.80–0.99). Consistent with previous reports, this association was stronger among participants consuming two or more alcoholic drinks per day (RR = 0.71, 95% CI 0.56–0.91). Conclusion:Our results are consistent with a modest reduction in colon cancer mortality associated with use of folic acid-containing multivitamins among moderate to heavy alcohol users.

We mailed a health survey to the 18,408 residents of a California retirement community and compared the 11,550 respondents on a number of characteristics by time of response. Early respondents were more likely to be the “worried well,“ that is healthy individuals who see their doctor regularly, receive disease detection screening, and follow healthful life-style practices. Later respondents tended to answer questions regarding their mental function and emotional status more negatively. Early and late respondents did not differ in the rates of death or hospitalization during the first 5 years of the study; non respondents had a higher incidence of hospitalization than respondents in year 1 and higher death rates in the first 3 years, but not thereafter. (Epidemiology 1993; 4:375–379)

A prospective cohort study of 318 human immunodeficiency virus 1 (HIV-1)-infected and 309 seronegative pregnant women was carried out in Butare, Rwanda. Birth weight was significantly lower among singleton infants born alive to HIV-1-infected mothers compared with those born alive to seronegative mothers (2706 g vs.2825 g; P= 0.002). Crown-to-heel length, head circumference, chest circumference and placental weight were also reduced. Maternal HIV-1 infection was significantly associated with intrauterine growth retardation but not with preterm birth. Differences in the body mass index and weight/head ratio suggest that the adverse impact on live born infants may have been most severe towards the end of pregnancy, resulting in a lean infant with a relatively large head. The higher frequency of intrauterine growth retardation could not be explained by potential confounding factors such as maternal cigarette smoking, history of sexually transmitted diseases or sociodemographic characteristics. The neonatal physical examination did not reveal any differences in clinical signs or symptoms within 48 hours of birth except for the presence of conjunctivitis which was more common among infants of HIV-1-infected mothers. The perinatal and neonatal mortality rates were not significantly affected by maternal HIV-1 status.

Objectives: This study evaluates time trends in colon and rectal cancer incidence and mortality among the three major race/ethnic groups (Hispanics, American Indians, and non-Hispanic Whites) in New Mexico (United States). Methods: We used data from the New Mexico Tumor Registry (NMTR) and computed average annual age-standardized incidence and mortality rates. Colon cancer incidence rates were further examined by anatomical subsite. Estimated annual percent change (EAPC) in incidence and mortality over time were computed using Poisson regression. Results: Invasive colorectal cancer incidence rates increased from 1969-89 in all three race/ethnic groups, but decreased among non-Hispanic Whites in 1990-94, while rates continued to increase among minority populations, especially among minority men. Over the 26-year period, EAPC in colon cancer incidence among men was 3.6 percent for Hispanics, 4.7 percent for American Indians, and 0.7 percent for non-Hispanic Whites. Right-sided colon cancers were more common among American Indian women, and among all women aged 65 years and older. Mortality rates decreased steadily among non-Hispanic Whites over the study period, especially among women. Conclusions: Studies are needed to identify important modifiable risk factors and to develop strategies to increase the use of colorectal cancer screening-procedures among the minority populations.

As part of a prospective study begun in 1981, we evaluated 8,600 postmenopausal women and 5,049 men residing in a southern California retirement community for risk factors for hip fracture. Incidence rates were twice as high in women as in men, but in both sexes the rates nearly doubled every 5 years between 70 and 90 years. Active exercise was strongly and negatively associated with hip fracture risk in both sexes; the age-adjusted relative risk was 0.6 and 0.5 for females and males, respectively, for 1 or more hours of exercise per day compared with less than 1/2 hour of exercise. A high body mass index (upper tertile of weight divided by height squared) was associated with a strong reduction in hip fracture risk for females (RR = 0.5). Current cigarette smokers had a significantly increased risk (RR = 1.8 and RR = 2.2 for females and males, respectively) compared with never-smokers, but the risk for past smokers was not different from that of lifetime nonsmokers. Other factors related to reduced hip fracture risk in women were high parity, late age at menarche, and long menstrual cycle length. These age-adjusted relative risk estimates did not change materially in multivariate analysis when adjusted simultaneously for age, active exercise, body mass, smoking, and, for women, age at menarche and number of children. Among estrogen users, the lowest risk of hip fracture was observed for recent users (RR = 0.8), while users who had stopped estrogen use 15 or more years ago had a relative risk of 1.1, suggesting that the protective effect of estrogen dissipates after many years since cessation of estrogen therapy

The conduct of public health surveillance and epidemiologicinvestigations would be enhanced by a cost-effective method for thecollection of population-based cancer risk-factor data. We assessed thefeasibility of ascertaining such data from hospital medical records duringroutine abstraction of information from a cancer registry. We examined themedical records of a representative sample of prostate and lung cancer casesdiagnosed during 1992 and 1993 from the New Mexico (United States) TumorRegistry (NMTR) database. Registry personnel abstracted ancillary informationfrom the medical records of 575 prostate and 273 lung cancer cases. Ofmedical records from 848 cases, 90 percent documented a history of tobaccouse, 77 percent contained any family medical history, and 48 percentdocumented occupational information sufficient to allow coding into standardoccupational groups. Availability of occupation and industry varied bypatient ethnicity, age at diagnosis, marital status , and type of hospital,indicating the potential for bias in studies using occupational informationfrom medical records. Our findings suggest that risk factor informationabstracted from medical records may provide valuable information for publichealth surveillance, but is generally too incomplete to serve as a singlesource of exposure information for etiologic studies. Family histories inmedical records may be sufficient for population-based ascertainment ofaffected relative pairs for genetic epidemiology studies for some cancertypes.

Minority women in New Mexico (United States)—including American Indian and Hispanic women—have shown disproportionately high incidence rates of invasive cervical cancer during the 1960s and 1970s. Several public health programs in New Mexico were directed toward early detection of cervical cellular abnormalities, particularly targeting the state's minority women. To evaluate the effectiveness of these programs, we examined the New Mexico Surveillance, Epidemiology, and End Results (SEER) data collected from 1969–92, and calculated average annual, age-specific, and age-adjusted incidence rates by ethnic group (American Indian, Hispanic, and non-Hispanic White) for five-year time intervals. We also calculated age-adjusted mortality rates for cervical cancer in the same ethnic groups using state vital records. Age-adjusted incidence rates for invasive cervical cancer show substantial temporal decreases, especially for minority women in the state. The age-adjusted incidence rate decreased by 66 percent, from 30.3 to 10.3 per 100,000 for American Indian women, and by 61 percent, from 26.1 to 10.2 per 100,000 for Hispanic women. A stage shift to earlier stages of cervical neoplasia occurred over the study period, with a substantially higher proportion of in situ compared with invasive cancers diagnosed in the most recent cf the most remote time period. The ratio of incidence rates of in situ to invasive cancers changed dramatically for both American Indian and Hispanic women. Cervical cancer mortality rates decreased steadily among Hispanic women from 1958 to 1992; the decrease among American Indian women was less stable and fluctuated due to small numbers. Ongoing targeted sceening programs should help to reduce cervical cancer incidence and mortality further in New Mexico.

Cancer surveillance is a fundamental component of national or sub-national cancer control planning and research. Cancer incidence and mortality data allow countries to monitor change in cancer incidence, mortality, and survival over time, by geographic region, and by demographic characteristics. Such data provide important clues to form hypotheses for cancer etiologic research, including research to examine environmental contributions to cancer. Strengthening cancer surveillance systems is urgently needed to conduct high quality research in environmental pollution and cancer in many countries. The United States National Cancer Institute Center for Global Health organized the first symposium on Environmental Contributions to Cancer during the 16th International Conference of Pacific Basin Consortium (PBC) for Environment and Health. PBC provided an important forum for dialog to establish partnerships and collaborations among researchers of environmental pollution and cancer.

This study evaluated risk factors associated with prevalent HIV-1 infection among pregnant women in a semi-rural but densely populated area surrounding the town of Butare in Rwanda. Overall seroprevalence was 9.3% in 5690 pregnant women who sought antenatal care at one of five health centres. Factors associated with higher seroprevalence of HIV-1 included history of multiple sexual partners, history of at least one sexually transmitted disease (STD), relatively high socioeconomic status (SES), being unmarried, young age at first pregnancy, and low gravidity. Women who had used oral contraceptives, smoked more than one cigarette per day, whose partners were circumcised, and had had sex to support themeselves were also at higher risk of being infected. A history of blood transfusion in the past 5 years was not associated with HIV-1 infection. History of multiple sexual partners, history of STD, high household income, partner circumcision, and past oral contraceptive use remained strongly associated with HIV-1 infection even when simultaneously controlling for other covariates. Among legally married women who lacked sexual behaviour risk factors, history of STD, high SES, young age at first pregnancy, and low gravidity were significantly assodated wlth HIV-1 seroprevalence.