Abstract 4460A: Meat-related compounds and colorectal cancer risk by anatomical subsite

Abstract

Abstract The most recent consensus statement issued by the World Cancer Research Fund and the American Institute for Cancer Research concluded that the evidence to support a positive association between intake of red and processed meat and colorectal cancer was convincing, yet the evidence for specific mechanisms explaining these associations remained inconclusive. To identify responsible compounds that may account for the previously observed statistical associations between meat and colorectal cancer, the present study examined associations between red meat, processed meat, and meat-derived heterocyclic amines (HCAs), polycyclic aromatic hydrocarbons (PAHs), nitrites, and nitrates and colorectal cancer in a population-based case-control study in central and northeast Pennsylvania. This population is at particularly high risk for colorectal cancer compared to the U.S. as a whole (54.5/100,000 in PA versus 48.8/100,000 in the U.S. at the start of this study in 2007). Participants (989 colorectal cancer cases and 1,033 healthy controls) completed a 137-item food frequency questionnaire, the National Cancer Institute's (NCI) Diet History Questionnaire (DHQ), which included a meat module that was linked to a database of nitrites and nitrates. The meat module also allowed for the use of NCI's Computerized Heterocyclic Amines Resource for Research in Epidemiology of Disease (CHARRED) software application to generate estimates of HCAs and PAHs. Odds ratios (ORs) and 95% confidence intervals (CIs) for associations between meat variables and colorectal cancer, stratified by anatomical subsite, were estimated from unconditional logistic regression models. After multivariable adjustment, there were no associations between red or processed meat and colorectal cancer. Nitrite plus nitrate intake was positively associated with proximal colon cancer (OR = 1.54, 95% CI = 1.03-2.31, P-trend = 0.025). A positive association was observed between 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (DiMeIQx) and colorectal cancer (OR = 1.36, 95% CI = 1.02-1.82, P-trend = 0.027). Total mutagenic activity was positively associated with distal colon cancer (P-trend = 0.049). There was no association between benzo[a]pyrene and total colorectal cancer or any sub-site. These results indicate that HCAs, PAHs, nitrites, and nitrates may be risk factors for colorectal cancer, but additional studies that examine risk factors stratified by anatomical subsite are warranted. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4460A. doi:1538-7445.AM2012-4460A