BQ chewers with the CYP26A1 rs4411227 C allele and CYP26B1 rs9309462 C allele had the highest risk of oral and pharyngeal cancer compared with the subjects carrying the CYP26A1 rs4411227 G allele and CYP26B1 rs9309462 T allele (aOR = 10.03; 95%  CI = 1.05–95.60). This evidence concerns the gene CYP26A1 and pharynx cancer.