OBJECTIVE To investigate whether polymorphisms in ERCC1,XPD,XPG,XRCC1 genes are associated with clinical outcomes inadvanced gastric cancer (AGC) patients treated with oxaliplatin-based chemotherapy.METHODS The genetic polymorphisms in ERCC1,XPD,XPG,XRCC1 were determined in 94 advanced gastric cancer patientstreated with oxaliplatin-based chemotherapy,using TaqMan-MGBprobes.The clinical response of 60 patients with stage Ⅳ disease,time to progression (TTP) and overall survival (OS) of 94 patientswere evaluated.RESULTS The overall disease control rate (CR + PR + SD) of the60 patients in stage Ⅳ was 70% (42/60).Patients with XRCC1 399G/G,XPG 46 C/C genotypes showed enhanced response to theoxaliplatin-based chemotherapy compared to those with othergenotypes (P<0.05).The median OS and TTP of the patientswere 5.5 months and 9.0 months,respectively.Among the 4types of polymorphisms in the study,XRCC1 399 G/A + A/A,XPG 46 C/T + T/T genotypes were regarded to be associatedwith chemoresistance and poor survival (P<0.05).Combinationanalysis of the 2 polymorphisms using the Kaplan-Meier methodrevealed that the TTP and OS of the patients with a number of riskgenotypes were significantly shortened (P<0.05).No significantassociation was found between the genotypes of the XPD codon751,the ERCC1 codon 118 and the clinical outcome (P>0.05).CONCLUSION Testing for XRCC1 399,XPG 46 polymorphismsmay allow identification of the gastric cancer patients whowill benefit from oxaliplatin-based chemotherapy.Specificpolymorphisms may influence clinical outcomes of AGCpatients.Selecting specific chemotherapy based on pretreatmentgenotyping represents an innovative strategy that warrantsprospective studies. OBJECTIVE To investigate whether polymorphisms in ERCC1, XPD, XPG, XRCC1 genes are associated with clinical outcomes in advanced gastric cancer (AGC) patients treated with oxaliplatin-based chemotherapy. METHODS The genetic polymorphisms in ERCC1, XPD, XPG, XRCC1 were determined in 94 advanced gastric cancer patientstreated with oxaliplatin-based chemotherapy, using TaqMan-MGBprobes. The clinical response of 60 patients with stage Ⅳ disease, time to progression (TTP) and overall survival (OS) of 94 patientswere evaluated .RESULTS The overall disease control rate (CR + PR + SD) of the 60 patients in stage IV was 70% (42/60). Patients with XRCC1 399G / G, XPG 46 C / C genotypes showed enhanced response to the oxaliplatin-based chemotherapy compared to those with other genotypes (P <0.05 ). The median OS and TTP of the patientswere 5.5 months and 9.0 months, respectively. Amm the 4types of polymorphisms in the study, XRCC1 399 G / A + A / A, XPG 46 C / T + T / T genotypes were considered to be associatedwith chemoresista nocturnal and poor survival (P <0.05) .Combinationanalysis of the 2 polymorphisms using the Kaplan-Meier methodrevealed that the TTP and OS of the patients with a number of riskgenotypes were significantly shortened (P <0.05) .No significantassociation was foundbetween the genotypes of the XPD codon 751, the ERCC1 codon 118 and the clinical outcome (P> 0.05). CONCLUSION Testing for XRCC1 399, XPG 46 polymorphisms allow the identification of the gastric cancer patients whowill benefit from oxaliplatin-based chemotherapy. Particular polymorphisms may influence the clinical outcomes of AGC patients .Selecting specific chemotherapy based on pretreatmentgenotyping represents an innovative strategy that warrants prospective studies.