Well-done meat consumption, NAT1 and NAT2 acetylator genotypes and prostate cancer risk: the multiethnic cohort study.

BACKGROUND Prostate cancer (PC) is the most common male malignancy in the United States and disparities in risk exist among ethnic/racial groups. A high intake of well-done meat and the presence of the rapid NAT1 and slow NAT2 acetylator genotypes, as modifiers of the carcinogenic effect of heterocyclic amines, were hypothesized to increase PC risk and possibly explain these ethnic differences in risk. METHODS This study examined the associations between well-done (red) meat consumption, NAT1 and NAT2 acetylator genotypes, and PC risk among five ethnicities (African American, Native Hawaiian, Japanese American, Latino, and Caucasian) in a case-control study of PC nested within the Multiethnic Cohort study. Cases (n = 2,106) and controls (n = 2,063) were genotyped for eight single nucleotide polymorphisms in NAT1 and seven single nucleotide polymorphisms in NAT2 that characterized all common alleles for these genes. Well-done meat intake was computed based on responses to a detailed food frequency questionnaire including a question on meat preference. Conditional logistic regression was used in the analysis. RESULTS There was no evidence of an increased risk associated with preference for well-done meat, intake of well-done meat, and NAT1 or NAT2 genotypes (jointly or separately). CONCLUSIONS These results do not support the hypothesis that exposure to heterocyclic amines is associated with risk of PC. However, additional studies with more precise exposure measures are needed.