The XPD Lys751Gln Polymorphism has Predictive Value in Colorectal Cancer Patients Receiving Oxaliplatin-Based Chemotherapy: a Systemic Review and Meta-analysis

Background: The predictive value of the xeroderma pigmentosum group D (XPD) Lys751Gln polymorphismregarding clinical outcomes of patients with colorectal cancer (CRC) receiving oxaliplatin-based chemotherapyhas been evaluated in numerous published studies, but the results remain inconclusive. Therefore, we performeda meta-analysis to determine the precise role of the XPD Lys751Gln polymorphism in this clinical situation andoptimize individual chemotherapy. Materials and
Methods: A multiple search strategy was used to identify eligiblestudies. Pooled odds ratios (ORs), generalized odds ratio (ORG) and their 95% confidence intervals (CIs) wereused to estimate the objective response, while hazard ratios (HRs) with 95%CIs were used for progression-freesurvival (PFS) and overall survival (OS).
Results: A total of 17 studies including 2,286 patients met the inclusioncriteria. Overall, the XPD 751Gln allele was associated with a non-significant reduced objective response tooxaliplatin-based chemotherapy in all patients or in the Asian and Caucasian subgroups. However, poor PFSand OS of CRC patients treated with oxaliplatin-based regimens were significantly related to the XPD 751Glnallele 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 stratifiedanalysis 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 CRCundergoing oxaliplatin-based chemotherapy.