• Environmental Analysis Health and Toxicology
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• v.12 no.3_4
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• pp.31-41
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• 1997

Public concerns about hazardous health effect from the exposure to organic by-products of the chlorination have been increased. There are numerous studies reporting that chlorination of drinking water produces numerous chlorinated organic by-products including THMs, HAAs, HANs. Some of these products are known to be animal carcinogens. The purpose of this study was to estimate health risk of DBPs by chlorinated drinking water ingestion in Seoul based on methodologies that have been developed for conducting risk assessment of complex-chemical-mixture. The drinking water sample was collected seperately at six water treatment plant in Seoul at March, April, 1996. In tap water of households in Seoul, DBPs were measured wilfh the mean value of 36.6 $\mu$g/L. Risk assessment processes,. which include processes for the estimation of human cancer potency using animal bioassay data and calculation of human exposure, entail uncertainties. In the exposure assessment process, exposure scenarios with various assumptions could affect the exposure amount and excess cancer risk. The reference dose of haloacetonitriles was estimated to be 0.0023 mg/kg/day by applying dibromoacetonitrile NOAEL and uncertainty factor to the mean concentration. In the first case, human excess cancer risk was estimated by the US EPA method used to set the MCL (maximum contaminant level). In the second and third case, the risk was estimated for multi-route exposure with and without adopting Monte-Carlo simulation, respectively. In the second case, exposure input parameters and cancer potencies used probability distributions, and in the third case, those values used point estimates (mean, and maximum or 95% upper-bound value). As a result, while the excess cancer risk estimated by US EPA method considering only direct ingestion tended to be underestimated, the risk which was estimated by considering multi-route exposure without Monte-Carlo simulation and then using the maximum or 95% upper-bound value as input parameters tended to be overestimated. In risk assessment for Trihalomethanes, considering multi-route exposure with adopting Monte-Carlo analysis seems to provide the most reasonable estimations.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.5
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• pp.2141-2144
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• 2014

Background: Gastric cancer is the second most common cause of cancer death. It has a poor prognosis with only 5-10% of hereditary etiology. If it is diagnosed, it could be helpful for screening the other susceptible members of a family for preventive procedures. Usually it is identified by symptoms such as presence of cancer in different members of family, some special type of pathology such as diffused adenocarcinoma, having younger age and multiple cancer syndromes. Hence, designing a registry program can be a more practical way to screen high risk families for a preventive program. Materials and Methods: Based on the inclusion criteria, a questionnaire was prepared. After pilot on a small number of patients, the actual data was collected from 197 patients and processed in SPSS 16.0. Results: Totally, 11.8% of the patients were younger than 45 years old. Blood type 'A' was dominant and males had a higher risk behavior with higher consumption of unhealthy food. Adenocarcinoma was reported in majority of cases. 21.8% of the patients had the including criteria for familial gastric cancer (FGC). Conclusions: The high percentage of FGC population compared to the other studies have revealed a need to design an infrastructural diagnostic protocol and screening program for patients with FGC, plus preventive program for family members at risk which could be done by a precise survey related to frequency and founder mutations of FGC in a national registry program.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7731-7735
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• 2014

Colorectal cancer (CRC) is the third most common cause of death due to cancer in the worldwide and the incidence is also increasing in Turkey. Our present aim was to investigate any association between germ-line methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms and CRC risk in Turkey. A total of 86 CRC cases and 212 control individuals of the same ethnicity were included in the current study. Peripheral blood-DNA samples were used for genotyping by StripAssay technique, based on the reverse-hybridization principle and real-time PCR methods. Results were compared in Pearson Chi-square and multiple logistic regression models. The MTHFR 677TT (homozygous) genotype was found in 20.9% and the T allele frequency 4.2-fold increased in CRC when compared with the control group.The second SNP MTHFR 1298CC (homozygous) genotype was found in 14.0% and the C allele frequency 1.4-fold elevated in the CRC group. The current data suggest strong associations between both SNPs of germ-line MTHFR 677 C>T and 1298 A>C genotypes and CRC susceptibility in the Turkish population. Now the results need to be confirmed with a larger sample size.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.1-13
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• 2012

Metabolic syndrome has become quite prevalent within our society. Over the past two decades, the prevalence of metabolic syndrome has sharply increased worldwide and it has become a major public health problem in several countries. It is associated with the global epidemic of obesity and diabetes mellitus and imposes numerous cardiovascular risks. Prostate cancer is the second most common cancer among men, surpassed only by non-melanoma skin cancer. A considerable body of evidence exists suggesting that some components of the metabolic syndrome have been associated with the risk of prostate cancer. These components include obesity, an abdominal fat distribution, and hyperinsulinemia. Androgen deprivation therapy (ADT) is the most widely used therapeutic modality in prostate cancer. It changed the body composition and lipid profile of men with prostate cancer. Androgen deficiency is associated with increased levels of total cholesterol, low-density lipoprotein (LDL)-cholesterol, increased production of proinflammatory factors, and increased thickness of the arterial wall and contributes to endothelial dysfunction. The aim of this review is to evaluate the association between metabolic syndrome and prostate cancer and to discuss the implications of androgen deficiency in men with cardiovascular risk factors. A comprehensive literature search was carried out with the use of PubMed from 1980 through 2011, and relevant articles pertinent to metabolic syndrome and prostate cancer are evaluated and discussed.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.2
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• pp.451-455
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• 2015

More than one million new patients suffer from breast cancer annually in the world. In developed countries, breast cancer is the most common malignancy diagnosed among women, and in developing regions, it often ranks second to cervical cancer. This study aimed to investigate the relationship between incidence of breast cancer and reproductive factors in North-West of Iran. This retrospective analytical control-case study was conducted with 235 breast cancer patients and 235 women in the control group. Data collection tools included a set of questions with interviews and patient medical records. Data were analyzed using statistical tests: t-test, Chi-square, Fisher, and Pearson correlation coefficient. Significantly increased risks were associated between breast cancer and older age at first pregnancy, age at menopause and history of contraceptive use. A trend for decreasing risk were observed with increasing parity. Findings of this study showed no association between breast cancer and age at menarche. The study results suggested that physiological and reproductive factors may play important roles in the development breast cancer among Iranian women.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5077-5083
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• 2013

Background: Breast cancer is the most frequent cancer in women globally and represents the second leading cause of cancer death among women (after lung cancer). India is going through epidemiologic transition. It is reported that the incidence of breast cancer is rising rapidly as a result of changes in reproductive risk factors, dietary habits and increasing life expectancy, acting in concert with genetic factors. Materials and Methods: In order to understand the existing epidemiological correlates of breast cancer in South India, a systematic review of evidence available on epidemiologic correlates of breast cancer addressing incidence, prevalence, and associated factors like age, reproductive factors, cultural and religious factors was performed with specific focus on screening procedures in southern India. Results: An increase in breast cancer incidence due to various modifiable risk factors was noted, especially in women over 40 years of age, with late stage of presentation, lack of awareness about screening, costs, fear and stigma associated with the disease serving as major barriers for early presentation. Conclusions: Educational strategies should be aimed at modifying the life style, early planning of pregnancy, promoting breast feeding and physical activity. It is very important to obtain reliable data for planning policies, decision-making and setting up the priorities.

• Journal of Digestive Cancer Research
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• v.1 no.2
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• pp.82-88
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• 2013

Cancer is the first leading cause of death in Korea and the second leading cause of death in the USA. There is extensive research into prevention of cancer and the support of oncology patients with diet or dietary supplements. In vitro and in vivo animal studies have indicated that antioxidants, including beta-carotene, alpha-tocopherol, and ascorbic acid, can yield anti-cancer effects in addition to providing protection against oxidative damage. Although many observational studies have shown that consuming fruits and vegetables can reduce the risk of some cancers, the results of several large-scale human intervention trials testing the benefits of a single or combined higher-dose of individual micronutrients have been inconsistent. Cancer can cause profound metabolic and physiological changes which may affect patients' nutrient requirements. Although the optimal route of nutrient delivery is through diet, cancer patients often suffer symptoms that disrupt their food intake, including anorexia, premature satiety, altered taste and smell, and changes in bowel mobility. In particular, micronutrient deficits can slow postoperative healing, contribute to depression symptoms, and decrease immune competence. Cancer patients are generally motivated to take dietary supplements to improve responses to treatment and quality of life. The Physician's Health Study II (PHS II) randomized controlled trial reported recently that daily multivitamin supplementation significantly, albeit modestly, reduced the risk of total cancer. Although evidence of multivitamin use benefits is limited in cancer patients, taking dietary supplements with constituents in the range of the recommended daily allowance according to the Dietary Reference Intake (DRI) recommendation is generally considered to be safe.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.7
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• pp.3113-3118
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• 2012

Introduction: Cancer is the second cause of death in Kuwaiti people after cardiovascular diseases. This study is the first in the country to describe epidemiological measures related to cancer in this population. Methods: Data obtained from the Kuwait cancer registry included all Kuwaiti patients between years 2000-2009. Analyses were conducted using age-specific rates, the age-standardization-direct method, 95% confidence intervals (95% CI), cumulative risk by the age of 74 years, limited-duration prevalence, mortality and forecasting to year 2029. Results: It was noted that the commonest cancer sites were colorectal with an age standardized incidence rate (ASIR) of 16.1/100,000 in males and breast (49.4/100,000) in the female population. The trend of cancer incidence (1974-2009) showed no statistically significant change. First causes of death due to cancer were female breast 8(6.4-9.6)/100,000 and lung (males) 8.1/100,000 (6.6-10.0). The risk of developing cancer by the age of 74 was 13.4% (1/8) and 14.3% (1/7) in males and females respectively, and the risk of dying from cancer in the same age group was 1/17 and 1/23. By the end of 2009, prevalent cases represented 0.52% of the Kuwaiti population. In the year 2029, the total number of cancer cases is expected to reach 1200 cases compared to 889 cases in 2009. Conclusions and recommendations: The most common cancers in Kuwait (breast, colorectal and lung) are largely preventable. Prompt and effective interventional prevention programs that vigorously involve diet, anti-smoking and physical activity for both sexes are urgently required.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.5609-5614
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• 2013

Background: Colorectal cancer is the third most common cancer in both men and women in the world and the second leading cause of cancer-related deaths. The incidence of colorectal cancer has increased in Iran in the past three decades and is now considered as a serious problem for our society. This cancer has two types hereditary and non-hereditary, 80% of cases being the latter. Considering that the relationship between SNPs with diseases is a concern, many researchers believed that they offer valuable markers for identifying genes responsible for susceptibility to common diseases. In some cases, they are direct causes of human disease. One SNP can increase risk of cancer, but when considering the rate of overlap and frequency of DNA repair pathways, it might be expected that SNP alone cannot affect the final result of cancer, although several SNPs together can exert a significant influence. Therefore identification of these SNPs is very important. The most important loci which include mutations are: MLH1, MSH2, PMS2, APC, MUTYH, SMAD7, STK11, $XRCC_3$, $DNMT_1$, MTHFR, Exo1, $XRCC_1$ and VDR. Presence of SNPs in these genes decreases or increases risk of colorectal cancer. Materials and Methods: In this article we reviewed the Genes and SNPs associated with non-hereditary and hereditary of colorectal cancer that recently were reported from candidate gene y, meta-analysis and GWAS studies. Results: As with other cancers, colorectal cancer is associated with SNPs in gene loci. Generally, by exploring SNPs, it is feasible to predict the risk of developing colorectal cancer and thus establishing proper preventive measures. Conclusions: SNPs of genes associated with colorectal cancer can be used as a marker SNP panel as a potential tool for improving cancer diagnosis and treatment planning.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.1
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• pp.57-61
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• 2010

Objective: Second primary malignancy (SPM) that occur in various period and region are important factors that deteriorate long-term survival rate in patients who recovered from oral cancer. Researches such as chemoprevention are being tried to reduce occurrence of SPMs. Only if analysis of clinical features of patients who develop SPM such as period, region and factors precedes, adequate prevention and treatment of SPM is possible. But, there are few researches about clinical features of SPMs that have primary lesion in oral cavity. In this study, we analysis that occurrence rates, regions that happen, risk factors and effect to survival rates of 2nd primary malignancies in oral cancer patients. From this survey, we willing to collect basic data for prevention and early diagnosis of SPMs. Methods: The medical records of 139 patients of oral oncology clinic of National Cancer Center who had up to 2-years follow up records after surgical or radiological treatment due to squamus cell carcinoma of oral cavity were reviewed. In these patients, survey of occurrence rate of SPMs, duration, survival rate and risk factors about occurrence of SPMs such as history of smoking, body mass index, age, sex, stage of primary lesion and history of radiologic treatment were achieved. Results: There are 15 patients who developed SPM in 139 cases. The actual occurrence rate of SPM was 10.79% and SPM were more likely to occur in male patients with 11 male Vs 4 female patients. Median age of these patient is 61.47 within 32 to 74 range. The regions that develop SPM are oral cavities (2 cases), stomach (4 cases), esophagus (2 cases), lung (2 cases) and others (1 case each breast, larynx, cervix, liver and kidney). In addition, metachronous cancers were 11 cases which happened more common than 4cases of synchronous cancers. Surveys of risk factors that relate to development of SPMs, such as sex, age, history of radiologic treatment, body mass index, history of smoking and stage of primary disease were done. Among them, factor of sex is only appear statistically significant (P=0.001), but rest are not significant in statistically. Conclusion: Occurrence rates of SPMs were reported from 10% to 20% by precede study. In this study, occurrence rate of SPMs is 10.79% that is similar to results of precede research. In comparison of 5-yr survival rates of groups that develop SPMs or not, there is statistically significance between two groups. Present treatment modalities of SPMs are surgical operation, radiotherapy, chemotherapy and combination of these modalities. In choosing the treatment modality, we must consider the first treatment modality, region of primary disease, region of SPMs and general conditions of patient. Because development of SPMs have big effect on prognosis, prevention of SPMs must regard to important objective of treatments in patients of SCCa in oral cavity.