GSTP1 polymorphism predicts treatment outcome and toxicities for breast cancer

This study aimed to investigate the association of the GSTP1 gene polymorphism with the outcomes and toxicities of treatments in breast cancer. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated for the association of GSTP1 polymorphism with tumour response and toxicities, and the hazard ratios (HRs) and 95% CIs were calculated for the association between GSTP1 polymorphism and overall survival (OS). The statistical analysis showed that the GSTP1 polymorphism was not associated with tumour response or OS. A significant increase in the incidence of toxicities was observed (GA vs. AA OR = 1.45, 95% CI = 1.04-2.01, P = 0.028; GG vs. AA OR = 1.47, 95% CI = 1.03-2.10, P = 0.036; recessive model OR = 1.54, 95% CI = 1.13-2.09, P = 0.006; and allele model OR = 1.35, 95% CI = 1.07-1.71, P = 0.011), especially in the chemotherapy ± surgery group (GA vs. AA OR = 1.64, 95% CI = 1.05-2.56, P = 0.030; recessive model OR = 1.72, 95% CI = 1.17-2.54, P = 0.006; and allele model OR = 1.57, 95% CI = 1.11-2.21, P = 0.010). Our results indicate that the GSTP1 polymorphism may be associated with increased toxicity, especially in patients treated with chemotherapy ± surgery.