ERCC1 expression as a predictor for chemosensitivity in recurrent colorectal cancer patients receiving cisplatinum (CDDP) plus S-1 chemotherapy.

13065 Background: To test the hypotheses of whether the relative mRNA expression of excision cross complement-1 (ERCCI) are associated with response to CDDP+S-1 chemotherapy in recurrent colorectal cancer (CRC). We assessed the relationship between ERCC1 mRNA expression levels and the response.,Thirty four patients with relapsed CRC were treated with cisplatin 30 mg/m on Day 1 and Day 8, and S-1 twice daily (BSA = 1.5 m, 60 mg/day) for 21 days, followed by a 2-week period of no treatment. cDNA was derived from paraffin-embeded tumor specimens to determine ERCC1 mRNA expression relative to the internal reference gene beta-actin using fluorescence-based, real-time reverse transcriptase polymerase chain reaction (Taqman) system.,Among 34 CRC patients, 4 patients were evaluated as CR, 13 as PR, and 17 as NC/PD. Relative ERCC1 mRNA gene expression level showed significant difference by the response with median expression levels of 0.70/1.33/1.80 in CR/PR/NC+PD patients respectively (P = 0.04).,These data suggest that intratumoral ERCC1 mRNA expression levels are independent predictive markers of response to CDDP+S-1 chemotherapy in colorectal cancer. No significant financial relationships to disclose.