Siriporn Kamsa-ard

Reproductive Risk Factors for Thyroid Cancer: A Prospective Cohort Study in Khon Kaen, Thailand

BACKGROUND Because of the gender disparity in the incidence of thyroid cancer, this study aimed to determine the association between reproductive factors and thyroid cancer. METHODS A total of 10,767 eligible women from the Khon Kaen Cohort, recruited and interviewed between 1990 and 2001, were followed up until 2011. The data were linked to the Khon Kaen Population-Based Cancer Registry to detect thyroid cancer cases. RESULTS There was 17 thyroid cancer cases detected, an incidence of 11.2 per 100,000 person-years, of which 70.6 % were papillary tumors. The incidence was apparently greater among those with an early age of menarche, nulligravida women, and oral contraceptive users. CONCLUSIONS There was a trend for thyroid cancer to develop in relation to longer estrogen exposure. This evidence is inconclusive but warrants further investigation.

Trends in Incidence of Hepatocellular Carcinoma, 1990 - 2009, Khon Kaen, Thailand

BACKGROUND Liver cancer is the most frequent cancer among Thais especially people in northeastern Thailand, but there has as yet been no assessment of trend. The data of all cancers in Khon Kaen can be retrieved from data base of the Khon Kaen Cancer Registry (KKCR) which was established in 1984. OBJECTIVE To assess the incidence trend of hepatocellular carcinoma in Khon Kaen, Thailand, between 1990 and 2009. METHODS Population-based cases of liver cancer registered between 1985 and 2009 were retrieved from the KKCR data base and cases with diagnosis of hepatocellular carcinoma (HCC) with the coding C22.0 according to ICD-O were selected. Incidence trends were calculated using the Jointpoint analysis. RESULTS There were 7,859 cases of HCC during the study period. Males were affected two times more frequently than females. The most common age group of cases was 50 and 69 years (60.3%). Most patients were diagnosed based on radiology imaging (40.6%) while the morphology verification was 7%. The age-standardized rates (ASR) were 13.1 to 49.8 per 100,000 among males and 4.8 to 38.4 per 100,000 among females depending on year of diagnosis since 1985. Remarkably, the ASRs were clearly low during first few years of starting the registration. The overall ASRs of HCC were 30.3 per 100,000 in males (95% CI: 25.9 to 34.6) and 13.1 per 100,000 (95% CI: 10.4 to 15.8) in females. During 1990-2009, the trends in incidences have been decreasing significantly with the annual percent change (APC) of 6.2% per year (95% CI: -7.6 to -4.8) in males and by 6.5% per year in females (95% CI: -8.4 to -4.9). CONCLUSIONS The incidence trends have been decreasing in both sexes. The recent decline in incidence may represent a falling risk.

Survival Time and Molecular Subtypes of Breast Cancer after Radiotherapy in Thailand

BACKGROUND Breast cancer is an important cause of death among women. One way of classifying different forms of breast cancer is by molecular features, usually in terms of the four subtypes: luminal A, luminal B, HER2-enriched, and triple negative. OBJECTIVES This study aimed to investigate the association between molecular subtypes and survival among breast cancer patients treated with radiotherapy. MATERIALS AND METHODS A retrospective cohort study was conducted. The subjects were 272 breast cancer patients who had received treatment in the radiotherapy unit at Srinagarind Hospital, Thailand, between 1 January, 1999, and 31 May, 2009. The end of the study was 1 June, 2014. Overall survival was defined as the time elapsing between initial registration at the radiotherapy unit and death or the end of the study. Survival curves were estimated by the Kaplan-Meier method, and a multivariate analysis was performed using Coxs proportional hazard regression model. RESULTS The patient mean age was 47.5±10.4 at the time of diagnosis. Of the 272 patients, 146 (53.7%) were classified as luminal A, 12 (4.4%) as luminal B, 30 (11.0%) as HER2-enriched, and 84 (30.9%) as triple negative. The overall survival rates at 1, 3 and 5 years were 87.1%, 68.4% and 59.2%, respectively. According to molecular subtypes, HER2-enriched patients had the lowest 5-year survival rate (30.0 %, 95%CI: 15.02-46.55). The median follow-up time was 8.37 years. In the Cox model analysis a higher risk of death was found for patients with HER2-enriched (HRadj=3.34, 95%CI:1.96-5.67), triple negative (HRadj=2.17, 95%CI: 1.44-3.27), and stage IIlB (HRadj=2.20, 95%CI: 1.16-4.17) cancers. CONCLUSIONS The worst survival rates were among patients classified as HER2-enriched, triple negative and at stage IIIB. Early detection and an advanced treatment modality are needed to help these patients.

Hormonal Contraceptive Use and Breast Cancer in Thai Women

Background Breast cancer is the most common cancer in women worldwide. We investigated the association of hormonal contraceptive use and breast cancer in Thai women. Methods A cohort study was conducted in Khon Kaen, Thailand. There were 70 cases of histologically confirmed breast cancer among 11 414 women aged 30 to 69 years who were recruited as participants in the cohort study during the period from 1990 through 2001. The study population was followed-up until December 31, 2011. To identify factors associated with incidence of breast cancer, hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using a Cox proportional hazards model. Results The 11 414 women provided a total observation time of 157 200 person-years. Breast cancer risk among women with a history of hormonal contraceptive use was 1.31 times that of women without such a history, but the difference was not statistically significant (95% CI, 0.65–2.65). No type of hormonal contraceptive was associated with a significant increase in breast cancer risk as compared with women who had never used hormonal contraceptives (oral contraception: HR = 1.35, 95% CI, 0.65–2.78; injection contraception: HR = 1.25, 95% CI, 0.56–2.80), and there was no relationship between duration of hormonal contraceptive use and breast cancer. Conclusions There was no association between hormonal contraceptive use and breast cancer; however, this finding should be viewed with caution due to the small number of cases.

Relationship between the body mass index and abnormal pap smears.

This cross-sectional analytic study aimed to investigate any relationship between the body mass index (BMI) and an abnormal Pap smear. The subjects were 7,720 women aged 30-69 years who lived in Khon Kaen Province, Thailand, and had been recruited as participants in the Khon Kaen Cohort Study during 1990-2001. All had received Pap smear screening for cervical cancer. The data were analyzed using descriptive and inferential statistics. Multiple logistic regression was used to determine the relationship between body mass index and an abnormal Pap smear. The mean BMI was 24.53 kg/m(2) (SD =3.98), and 2.14% had abnormal Pap smears. Compared with the reference group of women with a BMI ≤ 22.9 kg/m(2), those with a body mass index of 23.0- 24.9 kg/m(2) had a reduced risk of an abnormal smear (OR(adj) = 0.92, 95%CI: 0.57-1.47), but women with a BMI 25.0-29.9 kg/m(2) were found to have an approximately 1.24 times higher risk (OR(adj) = 1.24, 95%CI: 0.86-1.80), and those with a BMI ≥ 30.0 kg/m2 had an approximately 1.63 times higher risk (OR(adj)=1.63, 95%CI: 0.98-2.69). The results indicated that the risk of Pap smear abnormalities is increased in women who have a higher than normal body mass index, but this finding was not statistically significant. Nevertheless, public health personnel should encourage women to maintain their BMI in the normal range to reduce the possible future risk of cervical cancer.

Betel Quid Chewing and Upper Aerodigestive Tract Cancers: A Prospective Cohort Study in Khon Kaen, Thailand

BACKGROUND This study aimed to determine the association between betel quid chewing and the occurrence of upper aerodigestive tract (UADT) cancers. METHODS A cohort of 17,388 subjects, recruited and interviewed over the 1990-2001 period, in Khon Kaen, Thailand, was followed up until 2011. The data were linked to the Khon Kaen Population-Based Cancer Registry. RESULTS The prevalence of betel quid chewing was 15.9%, with a female predominance (97.7%); the mean age of chewers was 57.7 years (SD 6.6). The overall incidence of UADT cancers from the cohort was 14.7 per 100,000 person-years, whereas the incidence among the chewers was 45.7. Betel nut chewing was the only major risk factor for UADT cancers in this population (HR=5.26, 95%CI=2.51- 11.0), while weak associations were found for tobacco smoking and alcohol (HR=1.16, 95%CI=0.45-3.01 and 1.47, 95%CI=0.72-3.03 respectively). CONCLUSIONS We found betel quid chewing to be a main risk factor for UADT cancers, resulting in a higher incidence in females. However, further study is required to explore the potential risk factors among non-chewers, non-smokers, and non-drinkers.

Risk Factors for Colorectal Cancer in Thailand.

BACKGROUND Colorectal cancer (CRC) is one of the most common cancers worldwide. This study aimed to investigate the risk factors for colorectal cancer in the Thai population. MATERIALS AND METHODS A cohort study was carried out in Khon Kaen, Thailand, including 71 cases of histologically confirmed CRC patients among 19,861 participants, aged 30-69 years, who were recruited for a cohort study during the period 1990-2001. Participants were followed-up until 31 December, 2013. To identify factors associated with the incidence of colorectal cancer, hazard ratios were evaluated using Cox proportional hazard regression. RESULTS No environmental variables could be shown to be significantly related to the risk of CRC. Although in our sample, CRC was more prevalent among males, ex-smokers, and those who drank alcohol beverages ≥ 50 gram/day, but we could not demonstrate significantly associations (HRmale= 1.67, 95% CI, 0.80-3.49, HR ex-smokers = 1.34, 95% CI, 0.52-3.46, and HRalc≥ 50 = 1.08, 95% CI, 0.43-2.71). Individuals within the sample with a family history of cancer, working hour >8 hours per day, and current-smokers appeared to have decrease risk of CRC, but again these relationship could not be shown to be significantly associated (HRfam cancer= 0.96, 95% CI, 0.85-1.09, HRwork>8= 0.84, 95% CI, 0.36-1.93, and HRcurrent-smoker = 0.51, 95% CI, 0.18-1.38). CONCLUSIONS We found no evidence of environmental factors effecting the risk of CRC. There is a need for further research to determine why factors identified risk in other populations appear to not be associated with CRC risk in Thais.

Alcohol consumption and mortality: the Khon Kaen Cohort Study, Thailand.

Background The prevalence of alcohol consumption among Thais is high, around 30%. We quantified the relationship between alcohol drinking and mortality in a rural population in the most populous region of Thailand. Methods The data were from the Khon Kaen Cohort Study. About 24 000 Thai adults were enrolled between 1990 and 2001, and follow-up for vital status continued until March 16, 2012. Mortality data were obtained from the Bureau of Policy and Strategy, Ministry of the Interior, Thailand. A Cox proportional hazards model was used to analyze the association between alcohol drinking and death, controlling for age, education level, and smoking, and floating absolute risk was used to estimate the 95% confidence intervals of hazard ratios. Results In total, 18 457 participants (5829 men and 12 628 women) were recruited, of whom 3155 died (1375 men and 1780 women) during a median follow-up period of 13.6 years. Although alcohol drinking was common (64% of men and 25% of women), the amounts consumed were very low (average, 4.3 g/day in men and 0.8 g/day in women). As compared with never drinkers, mortality risk was lower among current drinkers and higher among ex-drinkers. Current drinking was not associated with mortality from cancer or diseases of the circulatory system, although ex-drinkers appeared to have a higher risk of death from the latter. Conclusions The leading causes of mortality were not associated with current alcohol drinking at the low consumption levels observed in this population.

Lack of Association between Red Meat Consumption and a Positive Fecal Immunochemical Colorectal Cancer Screening Test in Khon Kaen, Thailand: a Population- Based Randomized Controlled Trial

Background: There is convincing evidence from epidemiological studies that meat consumption increases colorectal cancer (CRC) risk. However, assessment of any association with a positive fecal immunochemical test (FIT) in CRC screening has been limited. If a link could be shown this might be helpful for establishing a risk group for colonoscopy. Objective: This study aimed to assess any association between meat consumption and other lifestyle factors and a positive FIT result in a Thai population. Methods: A cross-sectional analytical study was conducted with 1,167 participants in a population-based randomized controlled trial. CRC was screened from May 2016 - February 2017. Subjects aged 45-74 years who met the eligibility criteria were randomly allocated to the study arm. A positive FIT was determined with cut-off 100 ng/mL. Multiple logistic regression was used to analyze any relationship between lifestyle factors and a positive FIT. Result: The total number of subjects was 1,060 (90.8% return rate of FIT). With FIT100, FIT150, and FIT200, positive tests were found in 92 (8.68%), 74 (6.98%), and 60 (5.66%), respectively. No significant associations were noted with any of the variables, except for being aged 60-74 years (ORadj = 1.62, 95%CI: 1.03-2.54) Borderline significance was observed for high consumption of vegetables (ORadj = 0.62, 95%CI: 0.36-1.07) and being male (ORadj = 1.39, 95%CI:0.87-2.22). Conclusion: Despite the evidence from the literature, no association was here found between a positive FIT result and meat consumption or other well-established lifestyle parameters. Being aged 60-74 years was a risk factor which should be taken into account in CRC screening strategy in countries like Thailand with limited access to endoscopy.

Risk Factors for Cholangiocarcinoma in Thailand: A Systematic Review and Meta-Analysis

Background and objective: Cholangiocarcinoma remains a serious public health concern in Thailand. While many of the risk factors for cholangiocarcinoma in western countries are well-recognized, it remains unclear whether they are the same in Thailand. We set out to investigate the risk factors for cholangiocarcinoma in Thailand. Methods: Starting March 4, 2016, we reviewed studies found using pre-specified keywords on SCOPUS, Pro Quest Science Direct, PubMed, and online public access catalog of Khon Kaen University. Two review authors independently screened studies for inclusion criteria, extracted data, and assessed the studied Risk of Bias. The Newcastle-Ottawa Scale and the Joanna Briggs Institute Critical Appraisal Tools were used to assess the quality of included studies. The risk effects of factors were estimated as a pooled adjusted odds ratio with a 95% confidence interval. The heterogeneity of results was considered using the I-square, Tau-square and Chi-square statistics. Results: A strong association was found between cholangiocarcinoma and age, Opisthorchis viverrini infection, eating raw cyprinoid fish, family history of cancer, liquor consumption, and taking praziquantel. There was only a mild association found between eating nitrite-containing foods, fresh vegetables, education, smoking behavior, and sex. No association was found between cholangiocarcinoma and eating fermented fish (Pla-ra), northeastern Thai or Chinese sausage, sticky rice, meat, chewing betel nut, or eating fruit. There were two protective factors including fresh vegetables consumption and education attainment. Conclusion: There are unique risk factors of cholangiocarcinoma in Thailand, including age, Opisthorchis viverrini infection, eating raw cyprinoid fish, family history of cancer, liquor consumption, and taking praziquantel.