The predictive values of carcinoembryonic antigen (CEA) in patients with metastatic non-small cell lung cancer (NSCLC) treated with gefitinib

Abstract

22145 Background: Gefitinib inhibits the signaling of the EGFR tyrosine kinase and has shown activity in the treatment of advanced NSCLC, especially in Asian patients. Mutation in EGFR exon 19 and 21 have been shown to be the strongest predictor of response to gefitinib. Other clinical factors which also predict for response include female gender, adenocarcinoma, never smoker and Asian ethnicity. Recently, CEA was reported as a predictive factor of the efficacy of gefitinib and its level was associated with the frequency of EGFR mutation. Methods: We retrospectively reviewed records of 125 patients with metastatic NSCLC who received gefitinib as the only treatment and identified 24 cases that had at least one CEA serum level determined before starting gefitinib and response could be evaluated. 9 cases had serial serum CEA determined during the gefitinib therapy. Response was evaluated every 2 months by CT scans and using the RECIST criteria. Pre-treatment CEA>5 ug/L was defined as abnormal. Results: See T...