Dietary exposure to aflatoxin, or toxins produced by fungi affecting certain crops, may increase the risk for gallbladder cancer, according to new research.
“If aflatoxin is a cause of gallbladder cancer, it may have accounted for up to 20% of the gallbladder cancers in Shanghai, China, during the study period, and could account for an even higher proportion in high-risk areas,” investigators wrote.
While there is a known association between aflatoxin and an increased risk for hepatocellular carcinoma, researchers aimed to determine if there is also an association with an increased risk for gallbladder cancer. To do so, they compared aflatoxin B1 (AFB1)-lysine adducts in plasma samples from 209 patients with gallbladder cancer and gallstones and 250 controls with gallstones but without gallbladder cancer, identified within the Shanghai Biliary Tract Cancer case-control study.
They detected AFB1-lysine adduct in 32% of those with gallbladder cancer vs. 15% of controls (P < .0001). Thus, AFB1-lyine was almost three times more common in gallbladder cancer patients (OR = 2.71; 95% CI, 1.7-4.33).
Further, median AFB1-lysine levels were 5.4 pg/mg in those with gallbladder cancer who tested positive vs. 1.2 pg/mg in controls with detectable levels, and when comparing the highest vs. lowest quartiles, the odds ratio for gallbladder cancer was 7.61 (95% CI, 2.01-28.84).
They determined that the proportion of gallbladder cancers related to aflatoxin in the population was 20% (95% CI, 15-25).
Finally, they also evaluated 54 tumor tissue samples from patients with gallbladder cancer for the R249S mutation in TP53, which has a known association with aflatoxin exposure, but did not detect it in any of the samples.
“These findings of a strong association between aflatoxin and [gallbladder cancer] suggest that aflatoxin may be an important risk factor for [gallbladder cancer], which may have important public health implications,” the researchers concluded. “This study ... replicated the initial report from Chile in an independent study population from an entirely different part of the world.” – by Adam Leitenberger
Disclosures: The researchers report no relevant financial disclosures.