The Japan Collaborative Cohort Study (JACC Study) for Evaluation of Canner Risk sponsored by the Ministry of Education, Science, Sports and Culture of Japan (Monbusho): Report of Selected Results by Site
BACKGROUND: The objective of this study was to examine the mortality and incidence of stomach cancer in the Japan Collaborative Cohort Study (JACC Study), and compare them with those of the general population of Japan. METHODS: The cohort study involved 127,477 people living in 45 municipalities in Japan. The deaths due to stomach cancer were ascertained by death certificates. The age-adjusted mortality rate per 100,000 was calculated based on 110,792 subjects aged between 40 and 79 years at the baseline in all study areas. The incident cases were defined as the subjects in whom stomach cancer had developed, or subjects who died of stomach cancer during the observed period of survey for cancer incidence. The age-adjusted incidence rate per 100,000 was ascertained and calculated in 64,820 people aged 40-79 years at the baseline living in 24 study municipalities with cancer registries. Then, the mortality rate was compared with the mortality data published in vital statistics of Japan of 1995, and the incidence rate compared with the incidence data published in The Research Group for Populationbased Cancer Registration in Japan of 1992. RESULTS: During more than 10 years of follow-up, there were 582 male deaths and 287 female deaths due to stomach cancer. The age-adjusted mortality rate was 93.4/100,000 person-year (95% confidence interval [CI]: 84.6-102.2) in males and 31.1 (95% CI: 27.0-35.3) in females. There were 646 incident cases in males and 370 in females. The age-adjusted incidence rate was 245.3 / 100,000 person-year (95% CI: 221.6-268.9) and 94.8 (95% CI: 83.0-106.6) in males and females, respectively. CONCLUSION: The mortality rate of stomach cancer in the JACC Study was lower than that in the vital statistics in Japan. Similar incidence rate of stomach cancer seems to be found between data of the JACC Study and that of the Research Group for Population-based Cancer Registration, but care is needed to interpret this similarity, because it might be due to different degree of completeness of incidence survey between the 2 studies J Epidemiol 2005; 15: S89-S97.
BACKGROUND: Despite a declining incidence, stomach cancer is still a dominant cancer in Japan. The association between dietary habits and stomach cancer risk was investigated in a large prospective study in Japan. METHODS: Data were obtained using a self-administered questionnaire from 1988 through 1990. Food frequency questionnaire was used to evaluate the consumption of 33 selected food items. Proportional hazard model was used to determine the hazard ratios (HRs) and their 95% confidence intervals (CIs) of stomach cancer for different levels of the dietary intakes. RESULTS: A western style breakfast showed an inverse association with stomach cancer risk in males (HR=0.49, 95% CI: 0.35-0.70). Women who consumed liver three to four times per week and more than once per day had a significant increased risk, respectively (HR=2.02, 95% CI: 1.12-3.63, HR=3.16, 95% CI: 1.16-8.62 ). A clear dose-response relationship between the intake of liver and stomach cancer risk was observed. We found no association between stomach cancer mortality and the consumption of fruit such as mandarin orange, and vegetables such as carrots and spinach in both men and women. The consumption of high salt foods such as miso soup and pickles was also not significantly associated with the mortality of stomach cancer in both sexes. CONCLUSION: This prospective study suggested that a western-style breakfast is associated with a lower risk of stomach cancer, although some differences in the association were seen between men and women. J Epidemiol 2005; 15: S98-S108.
BACKGROUND: In Japan, green tea has been drunk for a long time. Because it can be drunk casually, many people love drinking it. If such green tea has an effect to prevent stomach cancer, it will be a very convenient way to prevent the disease. METHODS: To examine the association between green tea consumption and the risk of stomach cancer, past epidemiologic studies including JACC Study were reviewed. RESULTS: Among eight case-control studies, five showed risk reduction with a statistically significant difference, and two studies showed risk reduction without a statistically significant difference. The remaining study showed the opposite result. Among six prospective studies regarding stomach cancer, no study showed risk reduction with a statistically significant difference. Four of the six studies showed no relation. In terms of study design, prospective studies, which are considered to be more reliable than case-controlled studies, tend to show no risk reduction. The results of case-control studies and prospective studies present considerably different impressions. CONCLUSIONS: Prospective studies showed no inverse association between the consumption of green tea and the risk of stomach cancer. J Epidemiol 2005; 15: S109-S112.
BACKGROUND: Several epidemiologic studies reported the positive association between cigarette smoking and stomach cancer. The prevalence of smoking in men remains high in Japan compared to other developed countries. It is therefore of great importance to determine the impact of cigarette smoking on stomach cancer among the Japanese population. The Japan Collaborative Cohort Study (JACC Study) provided an opportunity to examine the association between smoking and the risk of mortality due to stomach cancer. METHOD: A baseline survey was conducted throughout Japan from 1988 through 1990 among 110,792 inhabitants of 45 areas. Data retrieved for 98,062 participants (43,482 male and 54,580 female) who provided sufficient information about their smoking habits, without any history of caner at the baseline. Of total 970,251 person-years, 757deaths due to stomach caner were identified. RESULTS: Current smokers were at a higher risk of death due to stomach cancer than non-smokers (Hazard ratio = 1.36; 95% confidence interval [CI]: 1.07, 1.73). The risk of stomach cancer for men who smoked 15 or more cigarettes per day was approximately 1.4-fold greater than that of non-smokers, and those who smoked 35 or more cigarettes per day had an approximately 1.7-fold higher risk of stomach cancer, although the dose-response trend among men was unclear (p for trend = 0.063). No associations between smoking and stomach cancer were detected among women. CONCLUSION: The present results, together with previous findings, strongly support a hypothesis that cigarette smoking increases the risk of stomach cancer in Japanese men. J Epidemiol 2005; 15: S113-S119.
BACKGROUND: The prognosis of stomach cancer with advanced stage remains poor. New biomarkers of the disease that may contribute to establish the potential screening strategy would be of value for the early detection of individuals at high risk of the disease. METHODS: We conducted a prospective, nested case-control analysis among apparently healthy men and women who were followed for up to 8 years in the Japan Collaborative Cohort (JACC) Study, to evaluate serum levels of insulin-like growth factor I, II, and binding protein 3 (IFG-I, IGF-II, and IGFBP-3), transforming growth factorβ-1 (TGFβ1), soluble fas (sFas) and superoxide dismutase activity (SOD) in 210 stomach cancer cases diagnosed in the JACC Study in relation to those levels in their 410 controls. RESULTS: Among 6 serum biomarkers tested for case-control differences, only sFas level in female stomach cancer cases was significantly higher than that of controls (2.22 pg/ml vs. 2.04 pg/mL, respectively; P = 0.013 by two-way analysis of covariance controlling for matching variable). CONCLUSION: None of the biomarkers consistently predicted future risk of stomach cancer in both men and women in the present analysis. Serum sFas level in women, however, should be studied much more thoroughly whether it provides meaningful refinement of risk stratification, or it elucidate the mechanisms of tumorigenesis in women. J Epidemiol 2005; 15: S120-S125.
BACKGROUND: Helicobacter pylori infection and serum pepsinogen values are strongly related with stomach cancer. The aim of this study was to know what were these factors among general population. METHODS: Subjects were randomly selected 633 control subjects in a nested case-control study for risk of stomach cancer. Most of them were from rural areas of Japan. Using frozen sera, pepsinogen I (PG I) and II (PG II) values and H. pylori antibody were measured. Those with PG I less than 50 ng/mL and the ratio of PG I to PG II (PG I/II) was less than 2.0 were defined as severe, those with PG I less than 70 ng/ml and PG I/II less than 3.0 were defined as mild and the other subjects were defined as no serological atrophy. RESULTS: About 70% of the subjects were H. pylori seropositive and the seroprevalence did not depend on age or sex. Percentages of those with severe serological atrophy increased with age from 10% in those aged 40-49 years to 38% in 70 and more, and percentages of those with mild serological atrophy were about 30% independent of age. CONCLUSIONS: The subjects, who were expected to represent populations of rural area of Japan, had high prevalence of both H. pylori infection and serological atrophy of gastric mucosa. These facts should be considered in discussing results of the nested case-control study. J Epidemiol 2005; 15: S126-S133.
BACKGROUND: In Japan, lung cancer is the top cause of cancer death in men and the third leading cause in women. Updated information on risk factors for lung cancer, therefore, is of great importance. The Japan Collaborative Cohort Study, a large prospective study started in 1988, has provided such information. METHODS: We reviewed published findings for lung cancer from the study. The endpoint was death from this cancer. RESULTS: The major findings were as follows. (1) The relative risks in current smokers versus nonsmokers were 4.46 in men and 3.58 in women. (2) Cigarette smoking accounted for 67.0% of lung cancer deaths in men and only 14.6% in women. (3) More than 15 years of smoking cessation may be required to decrease the risk of lung cancer to the level of never smokers. (4) A reduced risk was associated with frequent intake of green-leafy vegetables and fruit in men but not in women. These foods seemed to decrease the risk in male current or former smokers more than in female nonsmokers. (5) Serum levels of α- and β-carotenes,β-cryptoxanthin, and lycopene were inversely correlated with the risk in men. (6) In a preliminary study, serum 8-hydroxy-deoxyguanosine was higher in current smokers than in nonsmokers. CONCLUSIONS: The relative and attributable risks of smoking were smaller in Japan than in Western countries. In addition to smoking habits, therefore, we must pay attention to other risk factors for lung cancer or factors that modify the adverse effects of smoking including dietary factors. J Epidemiol 2005; 15: S134-S139.
BACKGROUND: Lung cancer mortality is inversely associated with high serum carotenoid levels and high intake of vegetables and fruits rich in carotenoids. The Japan Collaborative Cohort (JACC) Study was conducted to investigate whether serum levels of carotenoids, retinol, tocopherols, and folic acid were associated with risk for lung cancer death with follow-up through 1997. To examine the association by sex, we extended the follow-up and analyzed additional serum samples. METHODS: In the JACC Study, 39,242 subjects provided serum samples at baseline between 1988 and 1990. We identified 211 cases (163 men and 48 women) of death from lung cancer during about 10-year follow-up ending in 1999. Of the subjects who survived to the end of that follow-up, 487 controls (375 men and 112 women) were selected, and were matched to each case of lung cancer death for sex, age and participating institution. We measured serum levels of antioxidants in cases of lung cancer death and controls. Odds ratio (OR) for lung cancer death was estimated using conditional logistic models by sex. RESULTS: For men, the risk of lung cancer death was significantly lower for the highest quartile of serum α- and β-carotenes, lycopene, and β-cryptoxanthin than for the lowest quartile: the OR adjusted for smoking and other covariates were 0.41, 0.28, 0.46, and 0.39, respectively. For women, serum levels of α-carotene and zeaxanthin/lutein were inversely associated with risk of lung cancer, but the association was not significant. No association between lung cancer and serum levels of β-carotene, β-cryptoxanthin, and retinol was appeared among women. There was a suggestion that association between lung cancer and high serum levels of these components might differ between men and women. CONCLUSIONS: Higher serum levels of carotenoids appear to play a role in preventing death from lung cancer among Japanese men. Relationships between lung cancer and serum levels of some carotenoids appear to differ between sexes. However, further study with a large number of women cases needs to clarify the discrepancy between sexes. J Epidemiol 2005; 15: S140-S149.
BACKGROUND: This review discusses the epidemiologic features of bile duct and gallbladder cancer in Japan, mainly focusing on results of Japan Collaborative Cohort Study (JACC Study) for Evaluation of Cancer Risk Sponsored by the Ministry of Education, Science, Sports and Culture of Japan (Monbusho) in comparison with results of other studies. METHODS: The theses and papers derived from JACC Study on bile duct and gallbladder cancer were all collected for this review. Hirayama's cohort study, which is a representative epidemiologic study, and a large scale case-control study on bile duct and gallbladder cancer in Japan by Kato et al. were also taken into consideration. Small scale cross-sectional studies or ecological studies and the studies conducted outside Japan were collected by the literature reference services on the web net such as Pub Med or Japan Centra Revuo Medicina (Igaku- Chuo- Zasshi) limited to the published after 1980 and use key words bile duct cancer, gallbladder cancer and epidemiology. RESULTS: In the JACC Study, high intake of fried food was regarded as a factor that significantly elevated the risk of the diseases (hazard ratio [HR] = 2.58, 95% confidence interval [CI]: 1.08-6.16 in males; HR = 2.98, 95% CI: 1.28-6.86 in females). The JACC Study indicated that a high intake of boiled beans had a significant preventive relation to the diseases in females (relative risk [RR] = 0.50, 95% CI: 0.26-0.98). High consumption of fish also had a significant preventive relationship to bile duct cancer in males (RR = 0.53, 95% CI: 0.26-0.98) and gallbladder cancer in females (RR = 0.43, 95% CI: 0.24- 0.79). A history of blood transfusion also had a significant relationship (HR = 2.27, 95% CI: 1.29-3.98) as which elevated the risk. The JACC Study determined bowel movement as a risk factor. The group with bowel movements less than once per six days had a significantly elevated hazard ratio (HR = 5.21, 95% CI: 1.25-21.68). CONCLUSION: As to recent epidemiologic features of bile duct and gallbladder cancer revealed by the JACC Study, its outline became obvious in comparison with the results of other studies. Evidence for the contribution of the JACC Study is strong because it provides some important findings on the epidemiology of bile duct and gallbladder cancer. J Epidemiol 2005; 15: S150-S156.
BACKGROUND: The objective of this article was to overview the epidemiology of pancreatic cancer. We summarize the results of the Japan Collaborative Cohort Study (JACC Study) and some previous studies. METHODS: References were mainly in a Medline search through Pub Med database. In addition, 3 papers about the JACC Study were quoted. RESULTS : In the JACC Study, the standardized mortality ratio of pancreatic cancer was 0.97 in females and 0.84 in males. Diabetes mellitus (DM) has increased the risk for pancreatic cancer in many studies. In the JACC Study, DM had a risk for pancreatic cancer in males (hazard ratio = 2.12). Cigarette smoking has been associated with pancreatic cancer in many studies. In the JACC Study, the hazard ratio for current smokers was 1.6 in males, and 1.7 in females. The ratio was 3.3 who smoked 40+ cigarettes/day in males. In the JACC Study, alcohol intake was not associated with pancreatic cancer. These results are consistent with the other studies. Coffee consumption has not been associated with pancreatic cancer in many studies. In the JACC Study, the hazard ratio significantly increased to 3.19 among men who consumed 4+ cups of coffee per day. The relationships between diet /nutrition and pancreatic cancer are not clear in many studies. CONCLUSION: The relation between smoking and pancreatic cancer is most consistently described. A further analysis of the relationships between family history, hormonal factors in females, dietary and nutritional factors, obesity, physical activity and pancreatic cancer is necessary. J Epidemiol 2005; 15: S157-S167.
BACKGROUND: Host factors expressed by individual past medical history of hypertension, stroke, and myocardial infarction may have a relationship with colorectal cancer. METHODS: As part of the Japan Collaborative Cohort Study (JACC Study) for the Evaluation of Cancer Risk sponsored by the Ministry of Education, Science, Sports and Culture of Japan (Monbusho), we conducted a follow-up study of 110,792 Japanese inhabitants aged 40-79 years to reveal the relationship of past medical history of hypertension, stroke, and myocardial infarction at the baseline in 1988-1990 with colorectal cancer death for about 10 years up to the end of 1999. RESULTS: Past medical history of hypertension associated with an increased risk of female rectal cancer when analyzing all cancer cases with adjustment for age, body mass index, and exercise (hazard ratio [HR] = 1.97, 95% confidence interval [CI]; 1.13-3.43). Past medical history of myocardial infarction was also an increased risk for female rectal cancer (HR = 3.05, 95% CI; 1.28-7.28). Females who had a medical history of stroke had increased risk of rectal cancer without statistical significance. CONCLUSION: There was a positive association of past medical history of hypertension and myocardial infarction and an increased risk of rectal cancer in women. J Epidemiol 2005;15:S168-S172.
BACKGROUND: Because alcohol drinking is a potential risk factor for colorectal cancer, the trend in alcohol consumption in Japan may partly explain the increase in incidence and mortality rates of this malignancy until 1990-1995. METHODS: We analyzed data from the Japan Collaborative Cohort Study. From 1988 to 1990, 23,708 men and 34,028 women, aged 40-79 years, completed a questionnaire on lifestyle factors including drinking habits. Incidence rate ratios (IRR) were estimated by using proportional hazards models. RESULTS: During the mean follow-up of 7.6 years through December 1997, we documented 418 incidents of colon cancer and 211 of rectal cancer. Male ex- or current drinkers demonstrated a twofold risk for colon cancer compared with nondrinkers: the multivariate-adjusted IRR was 2.01 (95% confidence interval [CI] 1.09-3.68) for ex-drinkers and 1.97 (95% CI: 1.28-3.03) for current drinkers. The doseresponse relationship between alcohol consumption and the risk, however, was not clear. Female exdrinkers were at an increased risk without statistical significance. For rectal cancer, we found a slightly lower risk in light current drinkers who consumed less than 22 g ethanol per day: the multivariate IRR was 0.61 (95% CI: 0.33-1.13) for men and 0.69 (95% CI: 0.27-1.74) for women. Although the IRR for all current drinkers was almost unity in men, an increasing trend in risk was detected with increasing alcohol consumption in current drinkers (trend p = 0.027). CONCLUSIONS: Taking the findings from our study and other prospective investigations into consideration, more attention should be paid to alcohol consumption in the prevention of colon cancer in Japan. J Epidemiol 2005; 15: S173-S179.
BACKGROUND: Glucose intolerance may increase the risk of developing colorectal cancer. METHODS: In a sero-epidemiological nested case-control study, conducted as part of the Japan Collaborative Cohort Study (JACC Study) for Evaluation of Cancer Risk, we measured serum glycoalbumin in 123 patients with colorectal cancer and 279 controls. Conditional logistic regression was used to evaluate the risk of colorectal cancer. RESULTS: There were trends towards an association between high levels of glycoalbumin and an increased risk of colorectal cancer in men (odds ratio [OR] = 2.39; 95% confidence interval [CI]; 0.89- 6.36) and between high levels of glycoalbumin and a decreased risk of colorectal cancer in women (OR = 0.41; 95% CI, 0.14-1.04). CONCLUSIONS: A high level of glycoalbumin may increase the risk of colorectal cancer in men. The finding that high levels of glycoalbumin in women decreased their risk of colorectal cancer was inconsistent with previous reports, and may have been the result of limitations in the procedure in selecting samples and statistical power. J Epidemiol2005; 15: S180-S184.
BACKGROUND: Recently, it has been hypothesized that inflammation increases the risk of colorectal cancer. We investigated whether serum levels of C-reactive protein (CRP), a biomarker of inflammation, are associated with colorectal cancer, using serum samples collected in the Japan Collaborative Cohort Study (JACC Study). METHODS: We conducted a nested case-control study in the JACC Study, investigating the relationship between the risk for colorectal cancer and serum levels of CRP determined by a high-sensitivity CRP enzyme immunoassay. The subjects recruited were 141 patients with colorectal cancer (63 males and 78 females) and 327 controls with no history of cancer (148 males and 179 females). Each case of colorectal cancer was matched for sex, age and participating institution to 2 or 3 controls. We used ttest to analyze mean differences in CRP levels between colorectal cancer cases and controls. Odds ratios (ORs) and their 95% confidence intervals (CIs) were calculated using a conditional logistic regression model after adjusting for the potential confounding factors. RESULTS: Serum CRP levels were not clearly associated with the risk of colorectal cancer. The OR of the highest serum CRP levels was 1.18 (95% CI: 0.68-2.06) for colorectal cancer and 1.42 (95% CI: 0.73-2.74) for colon cancer, compared to subjects with lowest serum levels. The OR for incidence of colorectal cancer showed a similar trend, but the difference was not significant. Thus, high serum CRP levels did not appear to increase the risk of colorectal cancer. CONCLUSIONS: The present results suggest that high serum CRP levels are not associated with the risk of colorectal cancer in the JACC Study. J Epidemiol 2005; 15: S185-189.
BACKGROUND: The relationships between dietary habits and urothelial cancer have been discussed in many epidemiologic studies, however, they have not been sufficiently elucidated. In the present study, the associations of dietary habits with the risk of urothelial cancer incidence were evaluated taking into consideration sex, age, and smoking habits. METHODS: The Japan Collaborative Cohort Study (JACC Study) was planned in the late 1980s as a large-scale cohort study surveying people comprehensively and detailing their lifestyles, and the study subjects were followed up until the end of 1997. Among the total of 110,792 participants, 26,464 men and 38,720 women were in areas where incident cases with cancer were identified. During the observation period, 95 men and 28 women suffered from urothelial cancer. Hazard ratios for dietary factors were calculated by Cox's proportional hazards model. RESULTS: Increasing age, male gender, and smoking history were all significantly associated with the risk of urothelial cancer. High consumption of pork was significantly associated with the risk. In contrast, high intakes of milk and fresh fish were significantly inversely associated with the risk. High intakes of Chinese cabbage and fruits were also significantly inversely associated with the risk of urothelial cancer. CONCLUSIONS: It is suggested that high intakes of milk, fresh fish, Chinese cabbage, and fruits have preventive effects against urothelial cancer. J Epidemiol 2005; 15: S190-S195.
BACKGROUND: Phytoestrogens may be associated with a reduced risk of hormone dependent neoplasms such as prostate and breast cancers. We tried to determine the validity of the association between serum phytoestrogen concentrations and dietary habits obtained from a food frequency questionnaire used in the Japan Collaborative Cohort Study (JACC Study) for Evaluation of Cancer Risk sponsored by the Ministry of Education, Science, Sports and Culture of Japan (Monbusho). METHODS: The subjects were 151 male controls who were selected for a nested case-control study for evaluating prostate cancer risk as part of the JACC Study. Dietary habits were determined using a food frequency questionnaire at baseline, and the concentrations of genistein, daidzein, and equol in frozenstored serum samples assayed in 2002 were compared. RESULTS: Tofu intake showed a significant association with the serum concentrations of genistein and daidzein (Spearman's correlation coefficients (rs) =0.30 and 0.27, respectively), and miso soup showed a slight association with serum concentrations of these phytoestrogens. In contrast, serum concentrations of equol were not associated with dietary intake of tofu and miso soup. After adjustment for serum daidzein concentration, serum equol concentration was associated with the intake of foods containing fat, meat, and coffee, but not green tea. CONCLUSIONS: Serum genistein and daidzein concentrations were significantly associated with dietary intake of tofu, and slightly with intake of miso soup. Consumption of fat, meat, and coffee may be associated with equol production by intestinal microflora in this sample set. J Epidemiol 2005; 15: S196-202.
BACKGROUND: The incidence of kidney cancer is high in Western and Northern Europe and North America, and low in Asia. Although the incidence of kidney cancer in Japan is lower than the rates in the other industrialized countries, there is no doubt that it is increasing. METHODS: We evaluated the risk factors for kidney cancer death using the database of the Japan Collaborative Cohort (JACC) Study (i.e., medical history, anthropometry, and lifestyle including dietary habits). The analytic cohort included 47,997 males and 66,520 females aged 40 years and older. The Cox proportional hazards model was used to determine adjusted relative risks. RESULTS: A total of 36 males and 12 females died from kidney cancer during the follow-up of 9.6 ± 2.6 years and 9.9 ± 2.2 years, respectively. A medical history of hypertension, a fondness for fatty food, and consumption of black tea were associated with an increased risk of kidney cancer death while an intake of taro, sweet potato and potato was associated with a decreased risk. CONCLUSIONS: The present study showed four factors to be related to kidney cancer death. However, further studies may be needed to evaluate risk factors for kidney cancer death in Japan because the number of kidney cancer death in the present study was small. J Epidemiol 2005; 15: S203-S211.
BACKGROUND: Using a large-scale cohort of about 110,000 people established in 45 areas throughout Japan from 1988 through 1990, the study attempted to uncover the joint effects of combined smoking and alcohol intake on esophageal cancer mortality. METHODS: A cohort established from 1988 through 1990 included 46,465 men and 64,327 women aged 40 years and older and younger than 80. The number of female smokers and drinkers was low, and women were excluded from the analysis for that reason. In addition, 308 people with histories of malignant neoplasm, and 3,579 with unclear smoking and drinking data were also excluded, resulting in 42,578 people available for analysis. A follow-up of these individuals was conducted until 1999. Cox proportional hazards model was used for the analysis. RESULTS: The joint effects of number of cigarettes and amount of alcohol consumed per day were compared with non-smokers and non-drinkers or those consuming less than one unit of alcohol per day. An increased synergistic esophageal cancer mortality risk (3.88) for both smoking and drinking was observed for those smoking 20 cigarettes or less per day and drinking one unit of alcohol or more but less than three units per day, with the risk rising (6.30) for those smoking at least 21 cigarettes and drinking at least three units of alcohol per day. Even in non-smokers with increased alcohol consumption, and in non-drinkers or those drinking at most one drink per day with increased smoking, no increased risk was observed. CONCLUSIONS: In this cohort study of a Japanese population, increased esophageal cancer mortality risk was observed only when both factors of alcohol and tobacco intake were present simultaneously. J Epidemiol 2005;15:S212-S219.
BACKGROUND: We wished to determine the validity of the association between serum carotenoid concentrations and dietary habits obtained from a food frequency questionnaire in the Japan Collaborative Cohort Study (JACC Study) for Evaluation of Cancer Risk sponsored by the Ministry of Education, Science, Sports and Culture of Japan (Monbusho). METHODS: The subjects were 866 male and 569 female controls in nested case-control studies for evaluating the risk of lung, colorectal, and urothelial cancers as parts of the JACC Study. Dietary habits were assessed using a food frequency questionnaire, and serum samples were obtained at baseline. Serum carotenoid concentrations of frozen-stored sera were measured and compared with the results of the survey. RESULTS: In males, consumption of dairy products, some oily foods, vegetables, fruits, and boiled beans correlated positively with serum carotenoid concentrations, whereas ingestion of boiled rice and sansai (edible wild plants) was negatively correlated with serum carotenoids. In females, only fruit consumption was positively correlated with serum carotenoid concentration, whereas ingestion of butter, sansai, and potatoes were negatively correlated. Some specific associations, between serum lycopene and tomato consumption and between serum β-cryptoxanthin and ingestion of oranges, were observed in both sexes. CONCLUSIONS: In males, serum carotenoid concentrations were slightly associated with intake of foods rich in carotenoids. The lack of associations in females suggests that the food frequency questionnaire did not validly evaluate females' dietary habits concerning carotenoids in the JACC Study. J Epidemiol 2005; 15: S220-S227.