• Journal of Preventive Medicine and Public Health
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• v.48 no.6
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• pp.280-286
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• 2015

Objectives: Approximately 10% to 15% of lung cancer cases occur in never-smokers. Hormonal factors have been suggested to lead to an elevated risk of lung cancer in women. This systematic review (SR) aimed to investigate the association between hormonal replacement therapy (HRT) and the risk of lung cancer in women using cohort studies. Methods: We first obtained previous SR articles on this topic. Based on these studies we made a list of refereed, cited, and related articles using the PubMed and Scopus databases. All cohort studies that evaluated the relative risk of HRT exposure on lung cancer occurrence in women were selected. Estimate of summary effect size (sES) with 95% confidence intervals (CIs) were calculated. Results: A total of 14 cohort studies were finally selected. A random effect model was applied due to heterogeneity (I-squared, 64.3%). The sES of the 14 articles evaluating the impact of HRT exposure on lung cancer occurrence in women indicated no statistically significant increase in lung cancer risk (sES, 0.99; 95% CI, 0.90 to 1.09). Conclusions: These results showed that HRT history had no effect on the risk of lung cancer in women, even though the sES of case-control studies described in previous SR articles indicated that HRT had a protective effect against lung cancer. It is necessary to conduct a pooled analysis of cohort studies.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.13
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• pp.5389-5396
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• 2015

Diet is one of the major factors that can exert a majorly influence on colorectal cancer risk. This systematic review aimed to find correlations between various diet types, food or nutrients and colorectal cancer risk among Asian populations. Search limitations include dAsian populations residing in Asia, being published from the year 2008 till present, and written in the English language. A total of 16 articles were included in this systematic review. We found that red meats, processed meats, preserved foods, saturated/animal fats, cholesterol, high sugar foods, spicy foods, tubers or refined carbohydrates have been found by most studies to have a positive association with colorectal cancer risk. Inversely, calcium/dairy foods, vitamin D, general vegetable/fruit/fiber consumption, cruciferous vegetables, soy bean/soy products, selenium, vitamins C,E and B12, lycophene, alpha-carotene, beta-carotene, folic acid and many other vitamins and minerals play a protective role against colorectal cancer risk. Associations of fish and seafood consumption with colorectal cancer risk are still inconclusive due to many varying findings, and require further more detailed studies to pinpoint the actual correlation. There is either a positive or no association for total meat consumption or white meats, however their influence is not as strong as with red and processed meats.

• Toxicological Research
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• v.8 no.2
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• pp.317-329
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• 1992

Fifty chemicals are currently classified as human carcinogens based on epidemiologic and animal data. Humans are daily exposed to them from various sources of exposure via inhalation, dermal contact and oral ingestion. To reduce cancer risk to man, these human carcinogens should be appropriately regulated and monitored environmentally or biologically for routine human cancer risk assessment. A number of mathematical risk assessment models have been introduced, but any realistic and relevant model system is not available for humans. A mechanistic process for human cancer risk assessment was comprehensively reviewed and problems were also discussed. Here, a new conceptual approach using epidemiology and biological human monitoring was suggested for the most relevant method to study human cancer risk assessment.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.7023-7027
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• 2013

To evaluate the relationship between obesity, diet, physical activity and breast cancer in Thai women, we conducted a case control study with 1,130 cases and 1,142 controls. Informed consent was obtained from all participants and a structured questionnaire was performed by trained interviewers to collect information on demographic and anthropometric data, reproductive and medical history, residential history, physical activity and occupation as well as dietary habits. A significant positive association with an increased risk of breast cancer was observed in women body mass index (BMI) of ${\geq}25mg/m^2$ (OR=1.33, 95%CI 1.07-1.65), the risk being higher in postmenopausal women (OR=1.67, 95%CI 1.24-2.25). In addition, underweight BMI at ages 10 and 20 years showed an inverse association in all women (OR=0.70, 95%CI 0.56-0.88 and OR=0.74, 95%CI 0.59-0.93, respectively) and in those with a premenopausal status (OR=0.69, 95%CI 0.51-0.93 and OR=0.76, 95%CI 0.56-0.99, respectively). Regular exercise was associated with a decreased risk of breast cancer (OR=0.78, 95%CI 0.68-0.98). Interestingly, analysis by type of activity revealed significant protective effects for women who reported the highest levels of walking for shopping (OR=0.58, 95%CI 0.38-0.88). High consumption of vegetables and fruit were associated with a decreased risk of breast cancer, while high consumption of animal fat showed an increased risk in postmenopausal women. In conclusion, our results indicate that obesity and high consumption of animal fat are associated with breast cancer risk, particularly in postmenopausal women, while recreational physical activity has protective effects. It seems that primary prevention of breast cancer should be promoted in an integrated manner. Effective strategies need to be identified to engage women in healthy lifestyles.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.5
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• pp.2257-2262
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• 2014

A series of studies have explored the role of cytosolic serine hydroxymethyltransferase (SHMT1) C1420T polymorphism in cancer risk, but their results were conflicting rather than conclusive. To derive a more precise estimation of the association between C1420T and cancer risk, the present meta-analysis of 28 available studies with 15,121 cases and 18,023 controls was conducted. The results revealed that there was no significant association between the polymorphism and cancer risk overall. In stratified analysis by cancer type (breast cancer, gastrointestinal cancer, leukemia, lymphoma, and others), the results showed that 1420T allele was associated with decreased risk in leukemia (CT vs. CC: OR= 0.825, 95% CI =0.704-0.966; and CT+TT vs. CC: OR= 0.838, 95% CI = 0.722-0.973), but the same results were not present for other cancer types. When subgroup analysis was performed by source of control (population-based [PB] and hospital-based [HB]), a borderline inverse association was observed for the HB subgroup (CT vs. CC: OR= 0.917, 95% CI = 0.857-0.982) but not for the PB subgroup. Stratifying by geographic area (America, Asia and Europe), significant inverse association was only found in Asia subgroup (CT vs. CC: OR= 0.674, 95% CI = 0.522-0.870). In summary, the findings suggest that SHMT1 C1420T polymorphism is not associated with overall cancer development, but might decrease cancer susceptibility of Asians as well as reduce leukemia risk. Large well-designed epidemiological studies will be necessary to validate the risk identified in the current meta-analysis.

• Dementia and Neurocognitive Disorders
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• v.17 no.4
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• pp.137-147
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• 2018

Background and Purpose: Previous studies have suggested a decreased cancer risk among patients with Alzheimer's disease (AD). There remains a lack of data on the specific types of cancer and risk factors for developing cancer in AD. We evaluated the association between AD and cancer risk, and we examined specific types of cancer. Methods: A population-based longitudinal study was conducted using the National Health Insurance Service-Senior cohort for 2002-2013. A total of 4,408 AD patients were included in the study, as were 19,150 matched controls. Potential associations between the risk of cancer and AD were analyzed using Cox proportional hazard regressions. Results: Cancer developed in 12.3% of the AD group patients and in 18.5% of control group subjects. AD was associated with a reduced risk of cancer (hazard ratio [HR], 0.70; 95% confidence intervals, 0.64-0.78). The risk of head and neck cancers was significantly reduced (HR, 0.49), as were risks for cancers of the digestive tract, including stomach cancer (HR, 0.42), colorectal cancer (HR, 0.61), liver and biliary tract cancers (HR, 0.68), and pancreatic cancer (HR, 0.55). Lung and prostate cancer risks were also significantly lower for the AD group (HR, 0.52 and HR, 0.72, respectively). Conclusions: Our results showed an inverse association between AD and cancer. Further research involving a large number of patients in a hospital based-study is needed to address the biological associations between cancer development and dementia, including AD.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.7
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• pp.3993-4003
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• 2013

Scientific evidence for the primary prevention of cancer caused by physical activity of regular moderate-intensity or greater is rapidly accumulating in this field. About 300 epidemiologic studies on the association between physical activity and cancer risk have been conducted worldwide. The objectives of this paper were three-fold: (i) to describe briefly the components of physical activity and its quantification; (ii) to summarize the most important conclusions available from comprehensive reports, and reviews of the epidemiologic individual and intervention studies on a role physical activity in cancer prevention; (iii) to present proposed biological mechanisms accounting for effects of activity on cancer risk. The evidence of causal linked physical activity and cancer risk is found to be strong for colon cancer - convincing; weaker for postmenopausal breast and endometrium cancers - probable; and limited suggestive for premenopausal breast, lung, prostate, ovary, gastric and pancreatic cancers. The average risk reductions were reported to be 20-30%. The protective effects of physical activity on cancer risk are hypothesized to be through multiple interrelated pathways: decrease in adiposity, decrease in sexual and metabolic hormones, changes in biomarkers and insulin resistance, improvement of immune function, and reduction of inflammation. As there are several gaps in the literature for associations between activity and cancer risk, additional studies are needed. Future research should include studies dealing with limitations in precise estimates of physical activity and of a lack of consensus on what defines sedentary behavior of individuals and those linked with the proposed biomarkers to cancer risk and controlled exercise intervention trials.

• Journal of Nutrition and Health
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• v.37 no.7
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• pp.550-556
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• 2004

Dietary pattern analysis is important complementary approach for identifying associations between diet and chronic disease. A case-control study was conducted in order to examine dietary patterns and the risk of colon cancer in Korea. Data were collected from both 137 cases with either colorectal cancer or large bowl adenomatous polyps and 134 controls regarding social-demographic characteristics and food intake using a semi-quantitative food frequency questionnaire. We conducted factor analysis and identified 6 major dietary patterns: 'Well-being diet' characterized by higher intakes of potatoes, yogurt, soybean paste and vegetables, 'Meat & fish', 'Milk & juice', 'Pork & alcohol', 'Rice & kimchi', and 'Coffee & cake'. We calculated factor scores for each participant and examined the associations between dietary patterns and colon cancer risk. After adjusting for potential confounders, there was a relative risk for colon cancer of 0.16 (95% confidence interval, 0.07 - 0.34) when comparing the highest with the lowest tertile of the 'Well-being' pattern. Significant trends of decreasing risk of colon cancer also emerged with the 'Milk & juice' (OR = 0.40, 95% CI = 0.20 - 0.79). In contrast, inverse associations of the risk were found for 'Pork & alcohol' (OR = 1.92, 95% CI = 0.93 - 3.97), 'Coffee & cake' (OR = 2.18, 95% CI = 1.07 - 4.46). For the 'Meat & fish' pattern, the decreased risk of colon cancer was observed in the second tertile, but not in the highest tertile when comparing to the lowest. The 'Rice & kimchi' pattern had a nonsignificant association with the risk. These data suggest that major dietary patterns derived from the FFQ associated with the risk of colon cancer in Korea. Since foods are not consumed in isolation, dietary pattern research in natural eating behavior may be useful for understanding dietary causes of colon cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.5839-5842
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• 2013

Aim: We assessed the association between genetic variants of XPG, XPA, XPD, CSB, XPC and CCNH in the nucleotide excision repair (NER) pathway and risk of prostate cancer. Methods: We genotyped the XPG, XPA, XPD, CSB, XPC and CCNH polymorphisms by a 384-well plate format on the MassARRAY(R) platform. Multivariate logistical regression analysis was used to assess the associations between the six gene polymorphisms and risk of prostate cancer. Results: Individuals carrying the XPG rs229614 TT (OR=2.01, 95%CI=1.35-3.27) genotype and T allele (OR=1.73, 95%CI=1.37-2.57) were moderately significantly associated with a higher risk of prostate cancer. Subjects with XPD rs13181 G allele had a marginally increased risk of prostate cancer, with adjusted OR(95%CI) of 1.53 (1.04-2.37). Moreover, individuals carrying with CSB rs2228526 GG genotype (OR=2.05, 95% CI=1.23-3.52) and G allele (OR=1.56, 95%CI=1.17-2.05) were associated with a higher increased risk of prostate cancer. The combination genotype of XPG rs2296147 T and CSB rs2228526 G allele had accumulative effect on the risk of this cancer, with an OR (95% CI) of 2.23(1.37-3.59). Conclusions: Our study indicates that XPG rs2296147 and CSB rs2228526 polymorphisms are significantly associated with increased risk of prostate cancer, and that combination of XPG rs2296147 T allele and CSB rs2228526 G allele is strongly associated with an increased risk.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.659-663
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• 2013

Introduction: Squamous cell carcinoma of esophagus (ESCC) is one of the most common cancers in China. Preserved vegetables are processed foods and consumed in high amounts in the high risk areas for ESCC. This study aimed to investigate the relationships of preserved vegetable consumption with ESCC and precancer lesions. Methods: Cases from Yanting cancer hospital with pathological diagnosis of primary cancer, along with controls and individuals diagnosed with precancer lesions by endoscopy with iodine staining were interviewed. Trained staff collected data on dietary habits 1 year before the interview. An unconditional logistic regression model was used to estimate odds ratios of preserved vegetable consumption for precancer lesions and cancer. Results: Adjusting for potential confounders, intake of preserved vegetables (OR=2.92, 95%CI 1.32~6.47) and longer intake period (OR=5.78, 95%CI 2.26~14.80) were associated with higher risk of ESCC. Compared with lowest intake frequency, the highest was associated with a 3.0-fold risk for precancer lesions and 3.59-fold risk for ESCC (both p<0.05). Conclusion: Consumption of preserved vegetables is a risk factor for esophageal lesions in high risk areas. The carcinogenicity of preserved vegetables needs investigation in further studies and the public health strategies for reducing the consumption might be initiated in high risk areas.