Genetic polymorphism of aldehyde dehydrogenase 2 in patients with upper aerodigestive tract cancer

Background: Alcohol consumption is one of the major risk factors of the upp er aerodigestive tract (UADT) cancers; and combined cancers are frequently discovered in the patients with UADT cancer. The association between esopha geal cancer and alcohol-related metabolizing enzymes is well studied, but o nly a few examinations about the association between head and neck cancer a nd the enzymes were performed. Methods: Fifty-two patients with UADT cancer (head and neck cancer in 25, e sophageal cancer in 19, and multiple cancers in 8) were examined in the alc ohol habit and in the polymorphisms of aldehyde dehydrogenase 2 (ALDH2) and cytochrome P-4502E1. Results: Patients with multiple cancers had significantly higher ethanol co nsumption than the other two groups (p < 0.001). The frequency of ALDH2*1/2 *2 heterozygote was significantly lower (p = 0.009) in patients with head a nd neck cancer (5/25) than patients with esophageal cancer (11/19); The all ele frequency of P-4502E1 did not show a significant difference between the groups (p = 0.700). Conclusions: These results demonstrated the difference in the frequency of ALDH2 heterozygote between the patients with esophageal cancer and patients with head and neck cancer.