Association between alcohol, dietary factors and subsites of colorectal cancer: an ecological study

Background: Colorectal cancer is the fourth most common cancer, in terms of incidence throughout the world. There are some differences for risk factors involved in the incidence of tumor in different anatomical subsites of large bowel. However, most investigations have not studied the association between dietary factors and colorectal cancer subsites. Thus the current ecological study investigates the potential association between dietary factors and occurrence of cancer in different subsites of large bowel. Materials and methods: Data on colorectal cancer incidence and dietary factors was obtained by the subsites of colorectal cancer for the 32 countries were estimated between the years 1988 and 1992. The association between alcohol, dietary factors and cancer in different subsites of large bowel was then analyzed by using linear regression. Findings: Multivariate analysis showed a significant association between red meat consumption and proximal colon cancer incidence (p=0.02). In contrast, there was a significant association between alcohol consumption and distal colon cancer in men (p=0.03) and rectal cancer in both men and women (p=0.01 and p=0.04 respectively). Conclusion: Investigation on the incidence of cancer in anatomical subsites of large bowel separately might help us to identify etiological factors and preventive ways of this cancer.