Abstract 2825: Red meat and heterocyclic amine intake, metabolic pathway genes, and bladder cancer risk

Abstract

Abstract We analyzed the association between meat intake, heterocyclic amines and bladder cancer (BC) risk using data collected in a large case-control study. The study included 884 histologically confirmed BC cases and 878 healthy controls matched to cases by age (± 5 years), gender and ethnicity. Epidemiologic and dietary data were collected using structured questionnaires via an in-person interview. Dietary intake was reported on the National Cancer Institute- Block 135-item food frequency questionnaire (FFQ). Multivariate unconditional logistic regression was used to estimate odds ratios (ORs) and the 95% confidence intervals (95% CI). Compared to those in the lowest quartile of total red meat intake, the ORs for the second, third and fourth quartiles of total red meat intake were 1.04 (95% CI: 0.78-1.39), 1.58 (95% CI: 1.19-2.10), and 1.49 (95% CI:1.21-1.99), respectively (P-for trend =0.001). Higher intakes of beef steaks, pork chops and bacon were each associated with increased BC risk in a dose-response pattern. For example, the ORs for the second, third and fourth quartiles of beef steak intake were 1.04 (95% CI: 0.78-1.39), 1.19 (95% CI: 0.89-1.57), and 1.54 (95% CI: 1.17-2.04), respectively (P-for trend =0.001). In addition, high intake of fried chicken and fried fish also conferred significantly increased risk. When assessed in doneness level, compared to the rare done level, intakes of red meat with medium done and well done level were associated with 1.46- fold (95% CI: 1.13-1.89) and 1.94-fold (95% CI: 1.52-2.49) increased risk (P for trend<0.001). Intakes of heterocyclic amine (HCA) were available in a subset of 177 cases and 306 controls. Compared to the first quartile (the lowest quartile of intake), the ORs for the second, third, and fourth quartiles were 1.18 (95% CI: 0.63-2.23), 1.64 (95% CI: 0.89-3.00), and 2.58 (95% CI: 1.43-4.66), respectively (P for trend<0.001). We further assessed joint effects of red meat and genetic variants in the pathways relevant to HCA metabolism. We found that the risk associated with high red meat intake was most significant among subjects carrying high number of unfavorable genotypes in the pathway. Compared with subjects in the lowest quartile of red meat intake and who carried low number of unfavorable genotypes (less than 6), subjects carrying seven or more unfavorable genotypes and whose red meat intake was in the highest quartile were at 4.74-fold increased risk (95% CI=2.78-8.10; P<0.001). These results strongly support that red meat intake and genetic variants in the HCA metabolic pathways jointly influence bladder cancer susceptibility. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2825.