Slow acetylator genotype of N-acetyl transferase2 (NAT2) is associated with increased susceptibility to gallbladder cancer: the cancer risk not modulated by gallstone disease.

This study comprised 124 consecutive cases of proven GBC and 147 healthy controls. NAT2 polymorphisms were carried out using PCR-RFLP method. The NAT2 slow acetylator genotype was significantly associated with risk of GBC (OR 3.4, 95% CI =1.9-5.7 p = 0.000007). The NAT2 2*6 and 2*7 allele frequencies were higher in GBC and conferred significant risk of cancer (OR 1.9, 95% Cl = 1.2-2.9, p= 0.006; OR, 2.9, 95% Cl = 1.6-5.2, p = 0.0001). The haplotypes 2, 1, 1 and 1, 2, 1 were significantly higher (OR 3.7 95% Cl 2.1-7.0, p = 0.00001; OR 1.8 95% Cl =1.1-2.8, p = 0.008) in GBC. The risk of slow acetylator phenotype in GBC patients with or without gallstones was similar. These results suggest that NAT2 slow acetylator phenotype influences the susceptibility of gallbladder cancer and the risk is not modulated by gallstone disease.