Association of aflatoxin with gallbladder cancer in a case‐control study nested within a Chinese cohort

Abstract

AbstractWe evaluated whether aflatoxin B1 (AFB1) exposure was associated with later risk of developing gallbladder cancer (GBC). We measured AFB1‐lysine albumin adducts in baseline samples from the Shanghai Cohort Study of 18 244 men aged 45 to 64 years (recruited 1986‐1989). We included 84 GBC cases with sufficient serum and 168 controls matched on age at sample collection, date of blood draw and residence. We calculated adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) for detectable vs non‐detectable AFB1‐lysine albumin adducts and gallbladder cancer. AFB1‐lysine albumin adducts were detected in 50.0% of GBC cases, and risk of GBC was twice as high in those with detectable vs undetectable levels (OR = 2.0, 95% CI = 1.0‐3.9). ORs ranged from 1.8 (95% CI = 0.75‐4.3) for 0.5 to <1.75 pg/mg vs undetectable adduct levels to 2.2 (95% CI = 0.91‐5.6) for >3.36 pg/mg vs undetectable, suggesting a dose‐response (Ptrend = .05). When restricted to cases diagnosed before the median time to diagnosis after blood draw (18.4 years), results were similar (OR = 2.2, 95% CI = 0.80‐5.8) to those for the entire follow‐up duration. The OR was 9.4 (95% CI = 1.7‐51.1) for individuals with detectable AFB1‐lysine albumin adducts and self‐reported gallstones compared to individuals with neither. Participants with detectable AFB1‐lysine albumin adducts at baseline had increased risk of developing GBC, replicating the previously observed association between AFB1 exposure and providing the first evidence of temporality.