Role of N-acetyltransferase phenotype in human susceptibility to bladder carcinogenic arylamines.

N-acetyltransferase activity is species-specific and in animal experiments a determinant of the susceptibility of each species to arylamine bladder carcinogens. The effect of N-acetylation is that of inactivation. In humans, N-acetyltransferase activity is also genetically determined so that two N-acetyltransferase phenotypes exist, a rapid acetylator phenotype and a slow acetylator phenotype. N-acetyltransferase phenotype was determined in 71 bladder cancer patients and in 74 control subjects from Copenhagen. The distribution of the slow acetylator phenotype among the bladder cancer patients was 65% in control to 51% among the control subjects, indicating that the N-acetyltransferase phenotype also in humans may be a determinant of the susceptibility of each individual to arylamine carcinogens. In addition, this finding indicates that carcinogenic arylamines also play a role in bladder carcinogenesis in Copenhagen. Such studies may identify risk groups in a population and may reveal geographical areas with arylamine induced bladder cancer.