The XPD Lys751Gln polymorphism has predictive value in colorectal cancer patients receiving oxaliplatin-based chemotherapy: A systemic review and meta-analysis

Abstract

Background: The predictive value of the xeroderma pigmentosum group D (XPD) Lys751Gln polymorphism regarding clinical outcomes of patients with colorectal cancer (CRC) receiving oxaliplatin-based chemotherapy has been evaluated in numerous published studies, but the results remain inconclusive. Therefore, we performed a meta-analysis to determine the precise role of the XPD Lys751Gln polymorphism in this clinical situation and optimize individual chemotherapy. Materials and Methods: A multiple search strategy was used to identify eligible studies. Pooled odds ratios (ORs), generalized odds ratio (ORG) and their 95% confidence intervals (CIs) were used to estimate the objective response, while hazard ratios (HRs) with 95%CIs were used for progression-free survival (PFS) and overall survival (OS). Results: A total of 17 studies including 2,286 patients met the inclusion criteria. Overall, the XPD 751Gln allele was associated with a non-significant reduced objective response to oxaliplatin-based chemotherapy in all patients or in the Asian and Caucasian subgroups. However, poor PFS and OS of CRC patients treated with oxaliplatin-based regimens were significantly related to the XPD 751Gln allele in the dominant model (PFS: HR = 2.10, 95%CI: 1.65-2.67; OS: HR = 3.18, 95%CI: 1.57-6.47). On stratified analysis by ethnicity, these relationships were more pronounced in Asians (PFS: HR = 2.49, 95%CI: 1.79-3.47; OS: HR = 5.25, 95%CI: 3.46-7.94) than in Caucasians (PFS: HR = 1.73, 95%CI: 1.22-2.46; OS: HR = 1.78, 95%CI: 1.06-2.99). Conclusions: The XPD Lys751Gln polymorphism may have prognostic value in patients with CRC undergoing oxaliplatin-based chemotherapy.