Aspirin chemoprevention for colorectal tumor recurrence was significantly observed (P < 0.05) in the male nonsmoker subset of the J-CAPP cohort genotyped for CYP2A6*1/*4 and *4,*7,*9/*4,*7,*9, i.e., the putative impaired phenotype (Table 1). The gene discussed is CYP2A6; the disease is colorectal neoplasm.