GSTP1 and neoplasm: At 24 months of follow-up, patients with advanced tumours (26.3% vs. 83.3%, p = 0.02) and patients with the GSTP1 ValVal genotype (0.0% vs. 31.7%, p = 0.047) had shorter event-free survival (EFS) than those with localised tumours and those harbouring the GSTP1 IleVal or ValVal genotype (Fig. 1C).