Chemotherapy Response in East Asian Non-small Cell Lung Cancer Patients Harboring Wild-Type or Activating Mutation of Epidermal Growth Factor Receptors

Abstract

Previous exploratory analysis of epidermal growth factor receptor (EGFR) mutational status in tumor samples from randomized clinical studies suggested that patients with activating mutation of the EGFR had better survival than those harboring wild-type EGFR. We analyzed the EGFR sequence of tumor samples from advanced stage non-small cell lung cancer patients previously participated in treatment clinical trials. Responses to chemotherapy and survival of EGFR mutation-positive or -negative patients were compared. Tumor samples from 122 patients were available for analysis. EGFR mutation was present in 58 patients (47.5%). In 105 stage IIIB/IV patients, there was a nonstatistically significant trend toward a higher chemotherapy response rate of patients with mutated EGFR than those with wild-type EGFR (44.6% versus 30.6%, p = 0.162). Female, never-smoking, and adenocarcinoma patients lived longer than male (p = 0.0139), smoking (p = 0.0045), or nonadenocarcinoma (p = 0.0151) patients. There was no difference in the survival of patients with mutated or wild-type EGFR (p = 0.2159). There was no difference in progression-free survival of first-line chemotherapy between patients with wild-type or mutation in EGFR (6.6 months versus 6.1 months). There is a nonstatistically significant trend toward a higher chemotherapy response rate in patients with mutated EGFR than those with wild-type EGFR. EGFR gene mutation is not a predictive biomarker for progression-free and overall survival to cytotoxic chemotherapy in East Asians with advanced non-small cell lung cancer.