Some Japanese exhibit facial
flushing after drinking alcohol. Facial
flushing was considered to be caused by acetaldehydemia. The concentration of blood
acetaldehyde was concerned with the catalytic activity of
acetaldehyde dehydrogenase (ALDH).
Acetaldehyde dehydrogenase (ALDH)-2 polymorphism (rs671, Glu504Lys) was known to be associated with upper aerodigestive tract (UAT)
cancer due to modulation of ALDH2
enzyme activity. It remains controversial whether facial
flushing is useful in predicting UAT
cancer risk as a
surrogate marker of ALDH2 polymorphism. We conducted a case-control study to assess the risk of UAT
cancer and facial
flushing and ALDH2 polymorphism. Cases and controls were 585 UAT
cancer patients and matched 1170 noncancer outpatients of Aichi
Cancer Center Hospital. Information on facial
flushing and other lifestyle factors was collected via a self-administered questionnaire. Association between facial
flushing, polymorphism, and UAT
cancer was assessed by odds ratios and 95% confidence intervals by using conditional logistic regression models. The facial
flushing had no significant association with UAT
cancer, although ALDH2 Lys allele was significantly associated with UAT
cancer. No significant interaction between facial
flushing and alcohol consumption was observed in this study, whereas ALDH2 Lys allele had significant association with UAT
cancer. The misclassification between facial
flushing and ALDH2 genotype was observed in 18% of controls with ALDH2
Glu/Glu genotype and in 16% of controls with ALDH2 Glu/Lys genotype. Facial
flushing was less useful to predict UAT
cancer risk than genotyping ALDH2 polymorphism.