Asian Pacific Journal of Cancer Prevention, Vol 10, 2009 925 Food Intake and Colorectal Adenomas: A Case-Control Study in Malaysia Asian Pacific J Cancer Prev, 10, 925-932 Introduction Worldwide, more than ten million people are diagnosed with cancer and six million deaths occur every year (World Health Organization, 2003), while colorectal cancer (CRC) was estimated to be the third and fourth most commonly occurring cancer worldwide among men and women respectively in the year 2002. It was estimated to contribute to 9.5% and 9.3% of total cancer cases among males and females respectively in 2002 (International Association for Cancer Registries, 2002). Among Malaysians, colon cancer ranked third among cancers reported in males and females, accounting for 7.8% and 6.0% of all cancer cases in males and females respectively in 2003 (National Cancer Registry, 2003). It is a well-known fact that almost all CRCs arise from benign adenomatous polyps (Bond, 2000). These polyps are benign growths that protrude from the inner walls of colon and rectum, and are relatively common in people over the age of 50. American Society for Gastrointestinal Endoscopy (2006) estimated that an average 60 year-old without risk factors for polyps had a 25% chance of having Abstract It is well established that almost all colorectal cancers arise from benign, neoplastic adenomatous polyps. In previous studies, intake of fruits, vegetables and legumes were found to decrease the risk for colorectal adenomas (CRA) and colorectal cancer. This case-control study aimed to evaluate the role of a variety of foods in contributing to the risk of CRA in Malaysian subjects. One hundred and eighteen subjects were recruited into case (n=59) and control (n=59) groups at Hospital Kuala Lumpur (HKL). A pre-tested quantitative food frequency questionnaire (FFQ) was used to record the types of food items and frequency consumed. Logistic regression was used to determine the crude and adjusted odds ratios of the independent variables. Soy bean and soy products were associated with a reduced risk for CRA (OR = 0.38, 95% CI = 0.15-0.98), while tubers were associated with increase in risk four-fold (OR = 4.14, 95% CI = 1.60-10.70) and red meat intake was found to increase the risk two and a half-fold (OR = 2.51, 95% CI = 1.02-6.28). Higher servings of fruits and vegetables were found to significantly decrease the risk (OR fruits= 0.47, 95% CI = 0.30-0.74; OR vegetables = 0.49, 95% = 0.29-0.80). In conclusion, our data support protective roles for soy, fruits and vegetables in the aetiology of colorectal adenomas and increase in risk in those with high intakes of red meat and tubers. Food intake of an individual may have an influence on one’s risk for developing CRA. This finding warrants further investigation before the protective effect of these food items is to be accepted. New studies should explore the possibility of these associations among individuals in the general population especially with regard to different ethnic or other groups in Malaysia with low fruit and vegetable consumption. Key Words: Colorectal adenoma - FFQ - fruits - vegetables - red meat - soy a polyp. Although CRCs may arise from pre-existing adenomatous polyps or adenomas, however the progress of adenoma to cancer may take five to ten years (Young et al., 2002). Although true incidence of colorectal adenomas (CRA) are difficult to be calculated, Midgley and Kerr (1999) estimated its’ prevalence to be about 35% in Europe and USA, and between 10 - 15% in Asia and Africa. No Malaysian figure is available at this date. However, verbal information obtained from the experts in the field of colorectal cancer revealed that the figure may be between 10% and 20%. About 5% to 10% of adenomatous polyps are estimated to become malignant, a process that takes five to ten years (American Society for Gastrointestinal Endoscopy, 2006). The role of diet in the aetiology of CRC remains an area of active investigation. A predominantly plant-based diet is constantly associated with decreased risk of colorectal neoplasia. Intakes of fruits and grain appear to be inversely related to risk of CRC and polyps although less consistent evidence has been observed for vegetables (Pecipans & Sandler, 1994). Similarly, a recent study by Michels et al (2006) found that frequent consumption of RESEARCH COMMUNICATION Food Intake and Colorectal Adenomas: A Case-Control Study in Malaysia Amutha Ramadas 1 , Mirnalini Kandiah 2 1 School of Medicine and Health Sciences, Monash University, Sunway Campus, Bandar Sunway, 2 Department of Nutrition & Health Sciences, Faculty of Medicine & Health Sciences, Universiti Putra Malaysia, Selangor, Malaysia *For Correspondence: mirna@medic.upm.edu.my