Lifestyle-related risk factors for stomach cancer in northeast Thailand.

BACKGROUND: Stomach cancer is not common in Thailand but the life styles of the Thai population are changing to become more Western so that information for planning control programme of stomach cancer is necessary. The highest incidence rates of this neoplasm are found in Eastern Asia, ranging from age-standardized rates of 95.5/105 (men) and 40.1/105 (women) in Yamagata, Japan to 4.1/105 (men) and 2.1/105 (women) in Khon Kaen, Northeast of Thailand. In Thailand, the estimated age-standardized incidence rates in 1993, 1996 were 4.9/105, 4.1/105 in men and 3.0/105 , 2.6/105 in women. Risk factors for stomach cancer in Thai population are unclear, but possibly include low intake of vegetables and fruits, alcohol drinking, tobacco smoking and high intake of salt. OBJECTIVE: To investigate various aspects of dietary factors, smoking, and alcohol drinking in determining risk of stomach cancer in Thai population. METHODS: A case-control study was conducted in Khon Kaen, Thailand during 2002-2006, to study the role of these factors in stomach cancer. 101 stomach cancer cases and 202 matched controls (case : control = 1:2) by sex, age (? 3 years) and region were recruited from Srinagarind Hospital and Khon Kaen Regional Hospital, in Khon Kaen Province. All of cases were histologically confirmed. Controls had a variety of diseases, the main ones being disease of the eye. Information on dietary habits, alcohol drinking and smoking were collected by a structured questionnaire, blood samples were collected for further study. RESULTS: The distribution of the general characteristics by case-control status, the distribution of age and sex were similar in cases and controls. In the final analysis, the factors that found to be higher risk but not statistically significant were long-term filter cigarette smoking (OR=1.9, 95%CI: 0.85-4.50), long-term alcohol consumption (OR=1.2, 95%CI: 0.51-2.60) and low intake of vegetables and fruits (OR=1.2, 95%CI: 0.74-1.96). A high intake of vegetable oil (OR=4.5, 95%CI: 1.00.-20.17) was found to be associated with increased risk, and similar tendencies were noted for pork oil (OR=1.4, 95%CI: 0.63-3.01) and jeaw prik (mainly chilly with plara broth) (OR=1.2, 95%CI: 0 .76- 2.01). CONCLUSION: Our study confirmed protective effects of a high intake of fruits and vegetables against stomach cancer development and showed a high intake of sauces to increase risk of stomach cancer as in other countries in Asia.

Trends in incidences of stomach and colorectal cancer in Khon Kaen, Thailand 1985-2004.

BACKGROUND: The life styles of Thai people are changing with westernization and this would be expected to have an impact on the prevalence of cancer and other non-communicable diseases. For planning control programmes it is necessary to monitor change over time and the present study was conducted to provide information on stomach and colorectal cancer incidence rates in Khon Kaen Cancer Registry (KKCR), established in 1984 at the Faculty of Medicine, Srinagarind Hospital, Khon Kaen University. OBJECTIVE: To assess trends in urban and rural areas of Khon Kaen province during 1985 - 2004. METHODS: Data for stomach and colorectal cancer with an ICD-O diagnosis (coding C16 , C18 - C20) from the population-based cases of the KKCR, registered between 1985 and 2004, were retrieved and incidence trends were calculated using the Generalized Linear Model method (GLM), which generates incidence-rate-based logarithms. RESULTS: The study population comprised 2,530 cases, 721 of stomach (males 449, females 272) and 1809 of colorectal (males 976, females 833) cancer. Most cases were aged 35-75 years. According to the histopathological diagnosis, the most common was adenocarcinoma with over 90 percent. The overall age-standardized incidence rates (ASR) for stomach cancer were 4.5 and 1.4 per 100 000 in males and females, respectively, during 1985-1989, 3.7 and 2.0 during 1990-1994, 3.0 and 2.2 during 1995-1999 and 3.6 and 1.8 during 2000-2004 . The respective figures for colorectal cancer were 3.3 and 2.6, 4.6 and 3.1, 5.4 and 3.5 and finally 5.8 and 5.3. In both urban and rural areas males were affected more frequently than females, although a shift was evident towards decrease in the se ratio was evident for colorectal cancers over time. DISCUSSION: The results of this study showed slight increase in the incidence of colorectal cancer in Khon Kaen province, while rates for stomach cancer remained quite stable. The findings indicate a need for continuing research in stomach and colorectal cancer epidemiology, with subdivision into particular sites within these two sections of the gut.