A prospective study of lifestyle factors and the risk of pancreatic cancer in Nord-Trøndelag, Norway

Objectives: Cancer of the pancreas is highly fatal and, despite extensive scrutiny, only cigarette smoking stands out as a likely causal agent in epidemiological studies. To explore to what extent different lifestyle factors are associated with the risk of pancreatic cancer, data from a large health screening survey in a county in Norway were analyzed. Methods: Our study included 31,000 men and 32,374 women initially free from any diagnosed cancer, and during 12 years of follow-up, 166 incident cases of pancreatic cancer were diagnosed at the Cancer Registry. Results: Compared with never smokers, we found a two-fold increased risk among current smokers, and a dose–response association with number of cigarettes (p for trend = 0.02 for both men and women) and with number of pack-years (p for trend = 0.02 for men and 0.01 for women). The risk among former smokers quitting more than 5 years before study entry was close to the risk of never smokers. Compared with persons who reported never or infrequently to be physically worn out after a day's work, the relative risk (RR) among those who nearly always became worn out was 2.9 (95% confidence interval (CI) = 1.4–5.8) for men and 3.8 (95% CI = 1.6–9.2) for women. Divorced or separated men had a risk of 3.1 (95% CI = 1.3–7.2) compared with married men. We observed a higher risk among women in occupations of high socioeconomic status (RR = 2.5; 95% CI = 1.2–5.2), and among men occupied in farming, agriculture or forestry (RR = 2.1; 95% CI = 1.1–4.0), compared with persons in occupations of low socioeconomic status. Conclusions: Our results confirm the findings of previous studies that indicate a causal role of cigarette smoking in pancreatic cancer. Moreover, we found that the risk of former smokers may approach the risk of never smokers within a few years subsequent to quitting.     

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

For a case-control study of risk factors for renal cell carcinoma, a mailed questionnaire was used to collect data on 518 cases and 1,381 population-based controls in Ontario, Canada. Active cigarette smoking increased risk twofold among males (odds ratio estimate [OR]=2.0, 95 percent confidence interval (CI)=1.4–2.8) and females (OR=1.9, CI=1.3–2.6). Passive smoking appeared to increase risk somewhat among nonsmokers (males: OR=1.6, CI=0.5–4.7; females: OR=1.7, CI=0.8–3.4). A high Quetelet index (QI) was associated with a twofold increase in risk in both sexes, although this was based on reported weight at age 25 years for males (OR=1.9, CI=1.2–3.1) and five years prior to data collection for females (OR=2.5, CI=1.4–4.6). Diuretic use was associated with significantly increased risk among females, but not among males. Phenacetin use increased risk, while acetaminophen use was not associated with altered risk, although few subjects used either compound. Multiple urinary tract infections increased risk, but only significantly in females (OR=1.9, CI=1.2–2.9). Our data indicate the need for further exploration of passive smoking and diuretics as risk factors, as well as elucidation of mechanisms by which high lifetime QI and frequent urinary-tract infections might increase risk of this cancer.Des Kreiger, Marrett, and Darlington are with the Department of Preventive Medicine and Biostatistics, University of Toronto, and Division of Epidemiology and Statistics, Ontario Cancer Treatment and Research Foundation, Canada. Dr Dodds is with the Keproductive Care Program of Nova Scotia, formerly of the Ontario Cancer Treatment and Research Foundation, Canada. Ms Hilditch is with the Ontario Cancer Treatment and Research Foundation Epidemiology Research Unit, University of Toronto, Canada. Address correspondence to Dr Kreiger Department of Preventive Medicine and Biostatistics, 12 Queen's Park Crescent West, 3rd Floor, McMurrich Building, University of Toronto, Toronto, Ontario M5S 1A8, Canada. This study was funded by a grant #01692 of the Ontario Ministry of Health.     

Cigarette smoking,glutathione-s-transferase M1 and t1 genetic polymorphisms,and breast cancer risk (United States)

Objective: It has been suggested that functional polymorphisms in genes encoding tobacco carcinogen-metabolizing enzymes may modify the relationship between tobacco smoking and breast cancer risk. We sought to determine if there is a gene–environment interaction between GSTM1 (GSTM1A and GSTM1B), and GSTT1 genotypes and cigarette smoking in the risk of breast cancer. Methods: Cases and controls were recruited in a case–control study conducted in Connecticut from 1994 to 1998. Cases were histologically confirmed, incident breast cancer patients, and controls were randomly selected from women histologically confirmed to be without breast cancer. A total of 338 cases and 345 controls were genotyped for GSTM1 and GSTT1. Results: None of the GSTM1 genotypes, either alone or in combination with cigarette smoking, was associated with breast cancer risk. There was, however, a significantly increased risk of breast cancer among postmenopausal women with a GSTT1 null genotype (OR = 1.9, 95% CI 1.2–2.9). There were also indications of increased risk of breast cancer associated with cigarette smoking for postmenopausal women with GSTT1-null genotype, especially for those who commenced smoking before age 18 (OR = 2.9, 95% CI 1.0–8.8). Conclusion: Women with a GSTT1-null genotype may have an increased breast cancer risk, especially postmenopausal women who started smoking at younger ages.     

The contribution of cigarette smoking to bladder cancer in women (pooled European data)

Background: Using a combined analysis of 11 case–control studies from Europe, we have investigated the relationship between cigarette smoking and bladder cancer in women. Methods: Available smoking information on 685 female bladder cancer cases and 2416 female controls included duration of smoking habit, number of cigarettes smoked per day, and time since cessation of smoking habit for ex-smokers. Results: There was an increasing risk of bladder cancer with increasing duration of smoking, ranging from approximately a two-fold increased risk for a duration of less than 10 years (odds ratio (OR) = 1.9, 95% confidence interval (CI) 1.1–3.1) to over a four-fold increased risk for a duration of greater than 40 years (OR = 4.1, 95% CI 3.0–5.5). A dose–response relationship was observed between number of cigarettes smoked per day and bladder cancer up to a threshold limit of 15–20 cigarettes per day, OR = 3.8 (95% CI 2.7–5.4), after which no increased risk was observed. An immediate decrease in risk of bladder cancer was observed for those who gave up smoking. This decrease was over 30% in the immediate 1–4 years after cessation, OR = 0.68 (95% CI 0.38–1.2). However, even after 25 years the decrease in risk did not reach the level of the never-smokers, OR = 0.27 (95% CI 0.21–0.35). Conclusion: The proportion of bladder cancer cases among women attributable to ever smoking was 0.30, (0.25–0.35) and to current smoking was 0.18 (0.14–0.22). These attributable proportions are less than those observed among men, although they are likely to increase in the future as the smoking-related disease epidemic among women matures.     

Physical activity,medical history,and risk of testicular cancer (Alberta and British Columbia,Canada)

In order to evaluate risk factors for germ cell cancers, we conducted a case-control study of 510 men with testicular cancer aged 15 to 79 years and 996 randomly selected age-matched controls in the provinces of British Columbia and Alberta, Canada. Subjects completed a mailed questionnaire providing data on education level, ethnic origin, medical history, smoking, occupation, and recreational and sports activity. The response rate among cases was 80.3 percent and among controls was 68.1 percent. After controlling for age and ethnic origin, undescended testis was associated positively with risk of testicular cancer (odds ratio [OR]=3.5; 95 percent confidence interval [CI]=2.2–5.7) as was inguinal hernia requiring surgery (OR=2.0, CI=1.3–2.9), and hydrocoele (OR=2.6, CI=1.4–5.1). Risk of testicular cancer increased with height, with subjects taller than 180 cm having a significantly increased risk compared with those 174 cm or less (OR=1.5, CI=1.1–2.1). A moderate to high level of recreational activity level was associated inversely with testicular cancer risk (OR=0.6, CI=0.5–0.8).This project was supported by the National Health Research and Development Program (6610-1340-53) and by Health Canada through a contract from the Action Plan on Health and the Environment.     

Risk factors for renal cell carcinoma in Denmark. I. Role of socioeconomic status,tobacco use,beverages, and family history

Risk factors for renal cell carcinoma were examined in a population based case-control study in Denmark. A total of 368 cases and 396 age- and gender-matched controls were interviewed in their homes. Increased risk was associated with low socioeconomic status. For men, an increasing risk with decreasing socioeconomic status was seen (odds ratio [OR]=2.2, 95 percent confidence interval [CI]=1.0–4.6 for men in the lowest socioeconomic stratumcf the highest). For women, the risk was lower in the highest socioeconomic stratum compared with the rest (OR=2.4, CI=0.9–5.9 for the lowest stratacf the highest). Cigarette smoking was a risk factor in men with an OR=2.3 (CI=1.1–5.1) for cigarette smokers with a total consumption of more than 40 pack-years compared with nonsmokers. Family history of kidney cancer was associated with an increased risk in both genders (for men, OR=4.1, CI=1.1–14.9; for women, OR=4.8, CI=1.0–23). Observations were inconsistent regarding coffee and alcohol consumption, and we found no association with tea drinking. The association with socioeconomic status remained after adjustment for other factors.     

Cigarette and alcohol consumption and the risk of colorectal cancer in Shanghai, China.

The relation of cigarette smoking and alcohol drinking to colorectal cancer risk has been inconsistent in the epidemiological literature. In a population-based case-control study of colorectal cancer in Shanghai, China, where the incidence rates are rising sharply, we examined the association with tobacco and alcohol use. Cases were aged 30-74 years and newly diagnosed with cancers of the colon (N = 931) or rectum (N = 874) between 1990 and 1992. Controls (N = 1552) were randomly selected among Shanghai residents, frequency-matched to cases by gender and age. Information on lifetime consumption of tobacco and alcohol, as well as demographic and other risk factors, was obtained through in-person interviews. Associations with cigarette smoking and alcohol use were estimated by odds ratios (ORs) and 95% confidence intervals (CIs). Among women, the prevalence of smoking and alcohol drinking was low, and no significant association with colon or rectal cancer was observed. Although cigarette smoking among men was not related overall to colon or rectal cancer risk, there was a 50% excess risk of rectal cancer (OR 1.5, 95% CI 0.9-2.5) among those who smoked 55 or more pack-years. Among men, former alcohol drinkers had an increased risk of colon cancer (OR 2.3, 95% CI 1.4-3.7) but not rectal cancer, while current drinkers had a 30-50% excess risk of colon cancer only among those with long-term (30+ years) and heavy (>560 g ethanol/week) consumption. The excess risks were mainly associated with hard liquor consumption, with no material difference in risk between proximal and distal colon cancer. Although cigarette smoking and alcohol drinking in general were not risk factors for colorectal cancers in Shanghai, there were small excess risks for rectal cancer among heavy smokers and colon cancer among heavy drinkers.     

Alcohol Consumption, Smoking and Risk of Gastric Cancer: Case—Control Study from Moscow, Russia

Objectives: To examine the risk of gastric cancer associated with alcohol consumption and smoking in men and women in Moscow, Russia. Materials and methods: A case-control study which includes 448 cases and 610 controls was conducted. Cases consisted of patients with newly diagnosed histologically confirmed gastric cancer. Controls were patients admitted during the study period to the hospital with diagnoses other than cancer and/or gastrointestinal diseases. Information on demographic variables, smoking, alcohol consumption and diet was collected from all subjects. Venous blood was drawn from 361 cases and 441 controls. A serological test for Helicobacter pylori immunoglobulin G was performed. Results: Alcohol consumption, particularly vodka consumption, was found to increase the risk of gastric cancer. In men the effect of hard liquor drinking was stronger for cancer of the cardia (OR = 3.4, CI = 1.2–10.2), while in women the effect was stronger for cancer of sites other than gastric cardia (OR = 1.5, CI = 1.0–2.3). Smoking increased the risk of developing gastric cancer in men, but not in women. In men a dose-response relationship between mean number of cigarettes smoked per day (p = 0.03), pack-years of cigarettes smoked (p = 0.01) duration of smoking (p = 0.08) and the risk of cancer of gastric cardia was observed. Further statistical analysis revealed interactions between effect of smoking and alcohol consumption and between smoking and H. pylori infection status. Conclusions: The findings further support the role of alcohol consumption and smoking in the etiology of gastric cancer.     

A case-control study of thyroid cancer in women under age 55 in Shanghai (People's Republic of China)

A population-based interview study of 207 case-control pairs investigated reproductive, dietary, and other factors thought likely to increase thyroid cancer risk among women of reproductive age in Shanghai. Of particular interest were factors that might help explain the striking female over male excess in this age group. Risk was strongly associated with prior goiter or benign nodules (odds ratio [OR]=7.0, 95 percent confidence interval [CI]=2.5–27.5) and miscarriage as outcome of first pregnancy (OR=9.9, CI=2.0–48.4). Weaker associations were seen for women who were ever-pregnant (OR=2.1, CI=1.1–4.2), ever had an induced abortion (OR=1.6, CI=0.9–2.9), and ever used oral contraceptives (OR=1.7, CI=1.0–3.1). Compared with controls, cases gained significantly more weight from menarche to highest nonpregnant weight (P trend <0.01). Overall, cases ate more fish and shellfish, but there was no trend with level of consumption. More cases had a parent, sibling, or child with thyroid disease (OR=5.2, CI=2.5–12.1). Our findings relating to goiter and benign nodules and various reproductive factors support earlier studies. Consumption of seafood was difficult to evaluate; more detailed dietary data are needed to assess iodine intake.Drs Preston-Martin, Duda, and Mack are at the University of southern California School of Medicine, Los Angeles, CA, USA. Dr Jin is with the Shanghai Cancer Institute, Shanghai, People's Republic of China. Address correspondence to Dr Preston-Martin at the Department of Preventive Medicine, University of Southern California School of Medicine, Los Angeles, CA 90033, USA. This project was partially supported by awards SIG-2 and FRA-329 from the American Cancer Society.     

Smoking,alcohol, coffee,tea, caffeine,and theobromine: risk of prostate cancer in Utah (United States)

Data from a population-based study of newly diagnosed cases of prostate cancer (n=362) and age-matched controls (n=685) conducted in Utah (United States) between 1983 and 1986 were used to determine if cigarette smoking, alcohol, coffee, tea, caffeine, and theobromine were associated with prostate cancer risk. These factors were examined since their use differs in the Utah population, which is comprised predominantly of members of the Church of Jesus Christ of Latter-day Saints (LDS or Mormon), from most other populations. Pack-years of cigarettes smoked, alcohol intake, and consumption of alcohol, coffee, tea, and caffeine were not associated with prostate cancer risk. Compared with men with very low levels of theobromine intake, older men consuming 11 to 20 and over 20 mg of theobromine per day were at increased risk of prostate cancer (odds ratio [OR] for all tumors = 2.06, 95 percent confidence interval [CI]=1.33–3.20, and OR=1.47, CI=0.99–2.19, respectively; OR for aggressive tumors = 1.90, CI=0.90–3.97, and OR=1.74, CI=0.91–3.32, respectively). We present biological mechanisms for a possible association between prostate cancer and theobromine. This finding needs further exploration in studies with a wider range of theobromine exposures and more men with aggressive tumors.Dr Slattery is with the University of Utah School of Medicine, Salt Lake City, UT, USA. Dr West is with the Northerm California Cacer Center, Alameda, CA, USA. Address correspondence to Dr Slattery, Department of Family and Preventive Medicine, University of Utah School of Medicine, 50 North Medical Drive, Salt Lake City, UT 84132, USA. This study was supported in part by grant number CA 34804 from the US National Cancer Institute.     

Age and risk factors for colon cancer (United States and Australia): Are there implications for understanding differences in case-control and cohort studies?

Data from two population-based case-control studies were used to investigate the effect of age on colon cancer risk. Dietary intake data were assessed from a study conducted in Utah (United States) between 1979 and 1983; reproductive data were assessed from a study conducted in Adelaide (Australia) between 1979 and 1980. Data from both studies were assessed for their impact on those less than 65 years of age and those 65 or more years of age. Intake of energy, fat, and protein had a greater impact on risk among older men than among younger men. Risk estimates for the upper quartile of intake relative to the lowest quartile of intake were 8.5 (95 percent confidence interval [CI]=1.7–43.0) for energy, 8.2 (CI=1.6–41.3) for protein, and 7.2 (CI=1.6–31.4) for total fat for older men, while comparable risk estimates were 2.4 (CI=0.6–9.1) for energy, 3.0 (CI=0.7–13.6) for protein, and 1.9 (CI=0.5–7.1) for total fat among younger men. Similar trends were seen for older women for energy and protein. -carotene decreased colon cancer risk among younger men (odds ratio [OR]=0.4, CI=0.1–1.2) and women (OR=0.1, CI=0.1–0.5), although not among older men (OR=1.2, CI=0.3–4.9) and women (OR=1.9, CI=0.6–64). Calcium decreased risk of colon cancer among older men (OR=0.1, CI=<0.1–0.8) and younger women (OR=0.2, CI=<0.1–0.7). Women who were diagnosed at age 65 or older and were nulliparous had a tenfold increase in colon cancer risk (CI=2.4–47.9) relative to women who had an early age at first birth. Women diagnosed with colon cancer before age 65 did not experience an increase of colon cancer risk associated with being nulliparous. These data suggest that age at diagnosis may interact with other factors to alter risk of colon cancer.This study was supported by grant number R01 CA48998 and P01 CA50305 from the US National Cancer Institute. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the National Cancer Institute.     

Hormonal risk factors for endometrial cancer: modification by cigarette smoking (United States)

Objectives: To evaluate whether smoking modifies the risk of endometrial cancer associated with body mass index (BMI), postmenopausal hormone use, and other hormonal factors. Methods: Using multivariate adjusted models we examined interview data from a population-based case–control study of Wisconsin women (n = 740 cases, n = 2372 controls). Results: The relative risk for endometrial cancer associated with current smoking was 0.8 (95% CI: 0.6–1.0) compared to never smokers. No clear dose–response relationship was evident for pack-years smoked. When examined according to smoking status the risk associated with the highest quartile of BMI seemed to be greater among non-smokers (OR = 3.6, 95% CI: 2.4–5.3) than among current smokers (OR = 2.8, 95% CI: 1.4–5.6). Among postmenopausal women the risk associated with current use of postmenopausal hormones appeared to be greater among non-smokers (OR = 3.3, 95% CI: 2.3–4.9) than among current smokers (OR = 2.7, 95% CI: 1.3–5.5). Risk for long-term use (10 or more years) compared with never users was 8.3 (95% CI: 4.6–15.1) among never smokers and 2.5 (95% CI: 0.8–7.9) among current smokers. The risk associated with non-insulin-dependent diabetes was greater among non-smokers (OR = 2.5, 95% CI: 1.7–3.6) than current smokers (OR = 1.1, 95% CI: 0.4–3.1). There was no modifying effect of smoking on the risk associated with parity. Conclusion: These results suggest that smoking moderates the risk associated with endometrial cancer among women at greatest risk, specifically women who are obese or who use postmenopausal hormones.     

Alcoholism and cancer risk: a population-based cohort study

The incidence of cancer was studied in a population-based cohort of 9,353 individuals (8,340 men and 1,013 women) with a discharge diagnosis of alcoholism in 1965–83, followed up for 19 years (mean 7.7). After exclusion of cancers in the first year of follow-up, 491 cancers were observed cf 343.2 expected through 1984 (standardized incidence ratio [SIR] = 1.4,95 percent confidence interval [CI] = 1.3–1.6). A similar excess risk of cancer was seen among men (SIR = 1.4, CI = 1.3–1.6) and among women (SIR = 1.5, CI = 1.1–2.0). We observed the established associations with cancers of the oral cavity and pharynx (SIR = 4.1, CI = 2.9–5.7), esophagus (SIR = 6.8, CI = 4.5–9.9), larynx (SIR = 3.3, CI = 1.7–6.0), and lung (SIR = 2.1, CI = 1.7–2.6), although confounding by smoking likely increased these risk estimates. While there was evidence of increased risk for pancreatic cancer (SIR = 1.5, CI = 0.9–2.3), alcoholism did not elevate the incidence of cancer of the stomach (SIR = 0.9, CI = 6–1.4), large bowel (SIR = 1.1, CI = 0.8–1.5), prostate (SIR = 1.0, CI = 0.8–1.3), urinary bladder (SIR = 1.0, CI = 0.6–1.5), or of malignant melanoma (SIR = 0.9, CI = 0.3–1.9). Among women, the number of breast cancers observed was close to expected (SIR = 1.2, CI = 0.6–2.2), although a significant excess number of cervical cancers occurred (SIR = 4.2, CI = 1.5–9.1). The results of this study, one of the first to evaluate the incidence of cancer in a population-based cohort of alcoholics of both sexes, are consistent with smaller previous studies, which were usually limited to cancer mortality and of short follow-up.Dr Adami is with the Cancer Epidemiology Unit, University Hospital, Uppsala, Sweden. Drs McLaughlin and Hsing are with the Biostatistics Branch, National Cancer Institute, Bethesda, MD, USA. Dr Wolk is with the Cancer Epidemiology Unit, University Hospital, Uppsala, Sweden. Dr Ekbom is with the Department of Surgery and with the Cancer Epidemiology Unit, University Hospital, Uppsala, Sweden. Dr Persson is with the Department of Obstetrics and Gynaecology and with the Cancer Epidemiology Unit, University Hospital, Uppsala, Sweden. Address correspondence to Dr Adami, Cancer Epidemiology Unit, University Hospital, S-751 85 Uppsala, Sweden. The work was performed at the Cancer Epidemiology Unit, Uppsala University, Sweden; the research was supported by grants from the Swedish Cancer Society.     

Predictors of pancreatic cancer mortality among a large cohort of United States adults

Objectives: Cigarette smoking is considered an important risk factor for pancreatic cancer, but other purported risk factors are less well established. To learn more about the epidemiology of this important cause of mortality we examined associations with a variety of possible risk factors for death from pancreatic cancer in a large, prospective study of United States adults. Methods: We used proportional hazards models to obtain adjusted estimates of relative risks (hazards ratios). During 14 years of follow-up, 3751 persons died of pancreatic cancer in a cohort of 483,109 men and 619,199 women who had no reported history of cancer at enrollment in 1982. Results: Cigarette smoking at baseline was associated with fatal pancreatic cancer among men (multivariate relative risk [RR] = 2.1, 95% confidence interval [CI] 1.9–2.4) and among women (RR = 2.0, 95% CI 1.8–2.3). A trend in risk was observed with increasing number of cigarettes smoked per day among current smokers at baseline. With several variables included in separate models for men and women, we found additional factors to be predictive of pancreatic cancer mortality, including family history of pancreatic cancer, black race, diabetes, and increased body mass index. History of gallstones was predictive of pancreatic cancer among men. An inverse association with vegetable consumption was observed among men, that was not statistically significant. Conclusion: Our findings confirm that cigarette smoking is an important predictor of pancreatic cancer mortality, and identify several other factors that may contribute to increased risk.     

Reproductive factors and colon cancer: the influences of age,tumor site,and family history on risk (Utah,United States)

The Utah (United States) Population Database was used to evaluate the associations between reproductive factors and colon cancer risk and the impact that family history, age at diagnosis, and tumor site have on these associations. From the cohort of (White) women in the database, all first-primary cases of colon cancer (n=819) and controls who had complete fertility information (n=3, 202) were examined. The majority of tumors (68.6 percent) among women diagnosed at age 64 years or less were in the distal segment of the colon, while among women 65 or older, the majority of tumors (55.7 percent) were proximal. Women diagnosed before age 65 had a lower risk of colon cancer with increasing numbers of liveborn children (odds ratio [OR]=0.6, 95 percent confidence interval [CI]=0.3–0.9 for women with five or more children compared with women with one or two children). A long interval between first and second births (first birth-interval) was associated with increased risk of tumors in the distal segment of the colon (OR=1.4, CI=1.0–2.0) and among women diagnosed before age 65 (OR=1.6, CI=1.0–2.5); a longer, average birth-interval was associated with increased risk of proximal tumors (OR=1.5, CI=1.1–2.1). A longer, first birth-interval increased the risk associated with a family history of colon cancer, as did a longer average birth-interval and an older age at first or last birth. From these data, it appears that reproductive factors have heterogeneous effects on the risk of colon cancer that vary with age at diagnosis, tumor site, and family history of disease.This study was supported by grant and contract numbers CA48998 and CN0552 from the US National Cancer Institute. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the National Cancer Institute.     

Breast Cancer and Dietary Factors in Taiwanese Women

Objectives To examine the effect of the consumption of dietary factors on the risk of breast cancer in a case–control study in Taiwan.Methods Two-hundred-and-fifty cases and 219 age-matched controls between the ages of 25 and 74 were interviewed in person between 1996 and 1999. Usual consumption of dietary habits including 100 foods was assessed using a food frequency questionnaire and a nutrient database developed and validated in Taiwanese populations.Results Cases consumed significantly more fat than controls. Cases also consumed statistically significant less supplements such as vitamins and mineral than controls. Food group analyses showed that highest quartile of beef and pork intake significantly increased risk in younger women (OR = 2.5, 95% CI = 1.0–6.0) and all women (OR = 2.5, 95% CI = 1.1–3.3). The age- education- and total calorie-adjusted odds ratio (OR) of breast cancer risk comparing the highest and second highest quartile of fat intake to the lowest quartile was 5.1, 95% confidence interval (CI): 2.1–13 and 3.5, 95% CI: 1.4–8.7 among those younger cases (≤40). A multiple regression model indicates a protective effect of supplements (OR: 0.40, 95% CI: 0.3–07) and a harmful effect of dietary fat (OR: 2.6, 95% CI: 1.4–5.0) for the highest versus lowest quartile in all women.Conclusions Our results indicate a strong protective effect of dietary supplements and a harmful effect of dietary fats on the risk of breast cancer among women in Taiwan. These findings should be confirmed in future follow-up studies. Specific amount of dietary supplements and dietary fats should be quantified for a more accurate evaluation on the risk for breast cancer in this population.^★ Supported by the Koo Foundation Cancer Center Research Fund.     

Tobacco,alcohol, and diet in the etiology of laryngeal cancer: a population-based case-control study

Cancer of the larynx constitutes an increasingly important problem in Polish males during the last 25 years. A population-based case-control study of laryngeal cancer among people under 65 years of age was conducted in Lower Silesia, a province in Southwest Poland, from 1986 to 1987, with 249 newly-diagnosed cancer cases and 965 controls. The estimated relative risk (RR) for smoking and alcohol are both very high: for smoking more than 30 cigarettes, RR=59.7 (95 percent confidence interval [CI]: 13.0–274); for drinking vodka regularly for more than 30 years, RR=10.4 (95 percent CI: 4.0–27.2). Exposures to alcohol and tobacco show a clear multiplicative effect in all categories of exposure. The risk was shown to be reduced by quitting smoking (RR=0.3, 95 percent CI: 0.14–0.64, after 10 years) or by having a history of intermittent smoking. Poor nutrition was also identified as a strong independent risk factor. However, data quality regarding this factor is not as high as for tobacco and alcohol. Smoking alone accounts in this study for an estimated 95.2 percent of all the cases of laryngeal cancer.This work was conducted within the framework of the PR-6 Cancer Control in Poland-National Cancer Program and was supported by the Humboldt Foundation.     

Sexually transmitted diseases and other urogenital conditions as risk factors for prostate cancer: a case–control study in Wayne County,Michigan

Objective To investigate associations between prostate cancer and sexually transmitted diseases (STDs), prostatitis, benign prostatic hyperplasia (BPH), and vasectomy in a population-based case–control study in Wayne County, Michigan, among African American and white men aged 50–74 years.Methods: Incident prostate cancer cases (n=700) from 1996–1998 were identified from the Metropolitan Detroit Cancer Surveillance System. Controls (n=604) were identified through random digit dialing and Medicare recipient lists, and frequency matched to cases on age and race. History of potential prostate cancer risk factors was ascertained through in-person interview.Results: Prostate cancer was not associated with STD or vasectomy history. History of prostatitis was associated with prostate cancer among all subjects (odds ratio [OR]=1.8, 95% confidence interval [CI]: 1.1, 2.9) and in African American men (OR=2.2, 95% CI: 1.1, 4.6). History of BPH was associated with prostate cancer among all subjects (OR=2.4, 95% CI: 1.8, 3.3); significant associations were observed in both African American (OR=2.7, 95% CI: 1.6, 4.4) and white (OR=2.3, 95% CI: 1.5, 3.4) men.Conclusions: Among all subjects, prostate cancer was associated with prostatitis and BPH history, but not with STD or vasectomy history. Prevention efforts could be enhanced if inflammatory or infectious etiologies are found to be of importance in the subsequent development of prostate cancer.     

Bladder cancer: epidemiology and risk factors in Bulawayo,Zimbabwe

The incidence of bladder cancer, and the importance of some selected risk factors in its etiology, were estimated from the data collected in the cancer registry of Bulawayo, Zimbabwe, during the period 1963–77. Cancer cases were interviewed with a standard questionnaire, and more than 70 percent of these were complete. Incidence rates in the urban population of Bulawayo in the first 10-year period were relatively high, with age standardized rates of 17.9 per 100,000 in men and 9.5 in women. Risk-factor distribution was compared in 680 bladder cancer cases (494 males, 186 females) and a control group comprising other cases with non-tobacco-related cancers (8,201). Seventy-one percent of bladder cancer cases were squamous cell carcinomas. The presence of schistosomiasis, evaluated from past history of bilharzia or hematuria, was associated with a significantly increased risk of bladder cancer in both genders (odds ratio [OR]=3.9 for men, 5.7 for women), a result reflected in the differing risk by province of residence, which correlated with the prevalence of infection among cancer cases. The proportion of bladder cancer attributable to schistosomiasis was estimated to be 28 percent. Social status, as reflected by education level, also influenced risk (ORs for literatecf illiterate males=0.6), but tobacco smoking in men had no effect on the risk of squamous cell tumors. For transitional cell carcinomas or adenocarcinomas, there was a nonsignificant increased risk of 2.0 in the highest smoking categories (15 g of tobacco per day), compared with non smokers.     

Occupational risk factors for lung cancer among nonsmoking women: a case-control study in Missouri (United States)

Occupationally related risk of lung cancer among women and among nonsmokers has not been widely studied. A recently conducted population-based, case-control study in Missouri (United States) provided the opportunity to evaluate risk of lung cancer associated with several occupational factors. Incident cases (n=429) were identified through the Missouri Cancer Registry for the period 1986 through 1991, and included 294 lifetime nonsmokers and 135 ex-smokers who had stopped at least 15 years prior to diagnosis or had smoked for less than one pack-year. Controls (n=1,021) were selected through driver's license and Medicare files. Risk was elevated among women exposed to asbestos (ever: odds ratio [OR]=3.5, 95 percent confidence interval [CI]=1.2–10.0; >9 yrs: OR=4.6, CI=1.1–19.2) and pesticides (ever: OR=2.4, CI=1.1–5.6; >17.5 yrs: OR=2.4, CI=0.8–7.0). Risk also was elevated among dry cleaning workers (ever: OR=1.8, CI=1.1–3.0; >1.125 yrs: OR=2.9, CI=1.5–5.4). Occupational risks for lung cancer among women merit further study.Drs Brownson and Chang are with the Missouri Department of Health, Columbia, MO, USA. Dr Alavanja is with the Epidemiology and Biostatistics Program, National Cancer Institute, Rockville, MD, USA. Dr Chang directs the Missouri Cancer Registry with the Missouri Department of Health. Address correspondence to Dr Brownson, Division of Chronic Disease Prevention and Health Promotion, Missouri Department of Health, 201 Business Loop 70 West, Columbia, MO 65203, USA. This study was supported in part by US National Cancer Institute contracts NO1-CP7-1096-01 and NO1-CP7-1096-02.