Epidemiological evidence and association of human papillomavirus with esophageal cancer in northeastern Thailand: a case-control study.

Recently, epidemiological evidence of high-risk human papillomavirus (hrHPV) and its association with the increasing risk of esophageal cancer (EC) have been described. However, the involvement of such a virus in the pathogenesis of EC is still inconclusive in the literature. Therefore, our objective was to clarify the epidemiology of HPV infections in primarily diagnosed EC cases and validate this correlation with hospital-based control patients using a retrospective study with a case-control model. Here, we reported that the overall prevalence of HPV DNA was statistically associated with an increased risk of EC (OR, 3.3; 95% CI, 2.5-4.3). Interestingly, a history of gastroesophageal reflux disease (GERD) was constituted and significantly associated with HPV prevalence (adjusted OR, 4.6; 95% CI, 2.2-9.5). Furthermore, our meta-analysis in public databases also indicated that the combined OR and 95% CI between HPV infection and EC risk were 3.31 and 2.53-4.34, respectively, with significant heterogeneity (I2 = 78%). Variations in the geographic study, tissue type, and detection method remain potential predictors of heterogeneity. In addition, publication bias and sensitivity analysis were not observed, and the results exhibited stable outcomes. Collectively, we specify the recent epidemiological evidence in a validation of the distributed HPV, which might be statistically associated with an increased risk of EC. However, additional high-quality studies with larger sample sizes are needed to further verify the link between HPV and EC.

Relationship between Helicobacter Pylori Infection and the Risk of Esophageal Cancer in Thailand.

OBJECTIVE: Esophageal cancer (EC) is a multifactorial disease and a leading cause of mortality. Epidemiological and molecular studies have provided evidence that Helicobacter pylori (H. pylori) infection is an important cause of gastric carcinogenesis and thus, may be related to EC. However, esophagus H. pylori infection in Thai patients with newly diagnosed EC has not been reported. Moreover, the evidence of the association with H. pylori to EC is controversial. This study investigated the possible association between H. pylori infection with a virulence gene and EC in Thailand. METHODS: A case-control study was conducted that involved 105 newly diagnosed EC patients and 108 healthy controls. The prevalence of H. pylori infection detected in formalin-fixed, paraffin-embedded EC tissue in esophageal biopsy specimens from the subjects was measured using real-time PCR. All the data were collected in face to face interviews using a structured questionnaire. Multivariable unconditional logistic regression was used to calculate and analyses the odds ratios (ORs) of the data. RESULTS: A significant association was found between H. pylori infection and EC (p < 0.001, 95% CI:3.11-10.48). H. pylori-positive subjects had a 2.76 times higher risk of developing ESCC. Moreover, the H. pylori-positive subjects who were CagA-positive had slightly higher ORs and statistically significant risk factors. CONCLUSIONS: H. pylori infection was found to be associated with a risk of EC in Thailand, and among the H. pylori-positive subjects who were CagA-positive had a higher risk factor of ESCC but not of EAC.

The relationship between P16INK4A and TP53 promoter methylation and the risk and prognosis in patients with oesophageal cancer in Thailand.

DNA methylation can regulate the expression of tumour suppressor genes P16 and TP53, environmental factors, which are both important factors related to an increased risk and prognosis of oesophageal cancer (EC). However, the association between these two genes methylation status, as well as the effects of gene-environment interactions, EC risk remains unclear. A Hospital-based case-control study data were collected from 105 new EC cases and 108 controls. Promoter methylation status was investigated for P16 and TP53 genes using methylation-specific polymerase (MSP) chain reaction methods with SYBR green. Logistic and Cox regression models were used to analyse the association of P16 and TP53 promotor methylation status with EC risk and prognosis, respectively. Our results suggest P16, TP53 methylation significantly increased the risk of EC (OR = 5.24, 95% CI: 2.57-10.66, P < 0.001; OR = 3.38, 95% CI: 1.17-6.67, P < 0.001, respectively). In addition, P16 and TP53 promoter methylation status and the combined effects between environmental factors and its methylations in tissue were correlated with the EC risk and prognosis of EC patients. As a new biomarker, the methylation of P16 and TP53 can serve as a potential predictive biomarker of EC.

Association between infection with Campylobacter species, poor oral health and environmental risk factors on esophageal cancer: a hospital-based case-control study in Thailand.

BACKGROUND: Previous studies have shown the association between Campylobacter species infection and that environmental factors, poor oral hygiene in particular, are linked to an increased risk of esophageal cancer (EC). However, no study has reported on these factors in Thailand. Thus, this study's objective was to evaluate the impact of the relationship between Campylobacter infection and environmental factors on EC incidence in the population of Thailand. METHODS: Data from a case-control study were collected from 105 newly diagnosed EC cases and 105 controls recruited from 2007 to 2017. Infection with Campylobacter spp. was detected in the formalin-fixed paraffin-embedded (FFPE) tissue of EC taken from gastroesophageal biopsy specimens obtained from the participants, and evaluated using TaqMan® real-time PCR. Multivariable logistic regression was performed to calculate the odds ratios (ORs) and perform data analysis. RESULTS: Smoking, alcohol use, a family history of cancer, history of gastroesophageal reflux disease, poor oral hygiene and Campylobacter spp. infection were shown to be significant risk factors for EC (p < 0.05). The combination of poor oral hygiene and infection with Campylobacter spp. constituted significant risk for EC (p < 0.001). In addition, the risk of EC in subjects co-infected with C. rectus and C. concisus that practiced poor oral hygiene was even higher and was significant (ORadj = 4.7; 95% CI 2.41-9.98; p = 0.003). CONCLUSIONS: In Thailand, the major risk factors for EC are smoking status, alcohol drinking, family history of cancer, GERD, poor oral hygiene and Campylobacter spp. infection. This study found Campylobacter spp. prevalence to be associated with EC and appears to be enhanced by poor oral hygiene, suggesting that a combination of poor oral hygiene and Campylobacter species infection may together act as an important etiological risk factor for EC.

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.