Gastric and Colo-rectal Cancer Mortality in Viet Nam in the Years 2005-2006


Background: The International Collaborative Epidemiological Study of Host and Environmental Factorsfor Stomach and Colorectal Cancers in Southeast Asian Countries (SEACs) has been conducted in Viet Namfrom 2003 to 2008 on a case-control basis. For further effective primary prevention, we examined gastric andcolorectal cancer mortality nationwide ineight regions of Viet Nam in 2005-06.
Methods: Both demographicdata and lists of all deaths in 2005-06 were obtained from all 10,769 commune health stations in Viet Nam. Fiveindicators included name, age, sex, date of death and cause of death was collected for each case. We selected onlycommunes having the list of deaths with clear cause for each case and crude mortality rate for all causes from300-600/100,000 as published by the Ministry of Health for a reasonable accuracy and completeness. Obtaineddata for all causes, all cancers, stomach and colorectal cancer deaths as well as demographic information wereprocessed using Excel software and exported to STATA 8.0 for estimation of world age-standardized cancermortality rates per 100,000.
Results: Data were available for 1,246 gastric cases, (819 male and 427 female) withage-standardized mortality rates from 12.7 to 31.3 per 100,000 in males and from 5.9 to 10.3 per 100,000 infemales in the 8 regions of the country. For colorectal cancers, 542 cases (268 male and 274 female) gavemortality rates from 4.0 to 11.3 per 100,000 in males and from 3.0 to 7.8 per 100,000 in females. Discussion:Stomach cancer mortality in males in the region of North East in the North Viet Nam (2005-06) was higher thanthat in Japan (2002) (31.3 versus 28.7 per 100,000) while colorectal cancer in Viet Nam was lower. While prevalenceof Helicobacter pyloris infection in Viet Nam was from 70-75% in both males and females, the stomach cancerrate in males was significantly higher than in females, 31.3 versus 6.8 per 100,000, suggesting an influence ofother environmental risk factors. Whether protective factors are operating against colorectal cancer in VietNam now needs to be explored.