CYP2E1 and lip and oral cavity carcinoma: A case-control study of 41 male oral cancer patients and 123 healthy controls found that people with the CYP2E1 c1/c2 or c2/c2 genotype had a higher risk of oral cancer (multicovariate-adjusted OR = 2.0; 95% CI, 0.8–5.4) than those with the c1/c1 genotype [27].