title: Meat, meat cooking methods and preservation, and risk for colorectal adenoma.
abstract: Cooking meat at high temperatures produces heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs). Processed meats contain N-nitroso compounds. Meat intake may increase cancer risk as HCAs, PAHs, and N-nitroso compounds are carcinogenic in animal models. We investigated meat, processed meat, HCAs, and the PAH benzo(a)pyrene and the risk of colorectal adenoma in 3,696 left-sided (descending and sigmoid colon and rectum) adenoma cases and 34,817 endoscopy-negative controls. Dietary intake was assessed using a 137-item food frequency questionnaire, with additional questions on meats and meat cooking practices. The questionnaire was linked to a previously developed database to determine exposure to HCAs and PAHs. Intake of red meat, with known doneness/cooking methods, was associated with an increased risk of adenoma in the descending and sigmoid colon [odds ratio (OR), 1.26; 95% confidence interval (95% CI), 1.05-1.50 comparing extreme quintiles of intake] but not rectal adenoma. Well-done red meat was associated with increased risk of colorectal adenoma (OR, 1.21; 95% CI, 1.06-1.37). Increased risks for adenoma of the descending colon and sigmoid colon were observed for the two HCAs: 2-amino-3,8-dimethylimidazo[4,5]quinoxaline and 2-amino-1-methyl-6-phenylimidazo[4,5]pyridine (OR, 1.18; 95% CI, 1.01-1.38 and OR, 1.17, 95% CI, 1.01-1.35, respectively) as well as benzo(a)pyrene (OR, 1.18; 95% CI, 1.02-1.35). Greater intake of bacon and sausage was associated with increased colorectal adenoma risk (OR, 1.14; 95% CI, 1.00-1.30); however, total intake of processed meat was not (OR, 1.04; 95% CI, 0.90-1.19). Our study of screening-detected colorectal adenomas shows that red meat and meat cooked at high temperatures are associated with an increased risk of colorectal adenoma.
authors.affiliation: Nutritional Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Bethesda, Maryland, USA. sinhar@nih.gov
authors.forename: Rashmi
authors.initials: R
authors.lastname: Sinha
authors.forename: Ulrike
authors.initials: U
authors.lastname: Peters
authors.forename: Amanda J
authors.initials: AJ
authors.lastname: Cross
authors.forename: Martin
authors.initials: M
authors.lastname: Kulldorff
authors.forename: Joel L
authors.initials: JL
authors.lastname: Weissfeld
authors.forename: Paul F
authors.initials: PF
authors.lastname: Pinsky
authors.forename: Nathaniel
authors.initials: N
authors.lastname: Rothman
authors.forename: Richard B
authors.initials: RB
authors.lastname: Hayes
mesh_terms: D000236:Adenoma / Q000209:etiology*; D000368:Aged; D001564:Benzo(a)pyrene; D002273:Carcinogens; D015179:Colorectal Neoplasms / Q000209:etiology*; D003296:Cooking; D004032:Diet; D005260:Female; D005519:Food Preservation; D006801:Humans; D007093:Imidazoles; D008297:Male; D008460:Meat; D008875:Middle Aged; D009153:Mutagens; D011810:Quinoxalines
chemical_list: D002273:Carcinogens; D007093:Imidazoles; D009153:Mutagens; D011810:Quinoxalines; D001564:Benzo(a)pyrene; C036990:2-amino-3,8-dimethylimidazo(4,5-f)quinoxaline; C049584:2-amino-1-methyl-6-phenylimidazo(4,5-b)pyridine