Known as the PIONEER trial, this study was a prospective, multinational, epidemiological study of epidermal growth factor receptor (EGFR) mutations in patients from Asia with newly diagnosed advanced lung adenocarcinoma. Eligible patients had untreated stage IIIB/IV adenocarcinoma. EGFR mutation status of tumor samples was determined. The results showed that of 1482 patients from seven Asian regions, 43.4% of patients were female, median age was 60 years (range, 17-94), and 52.6% of patients were never-smokers. EGFR mutation status was evaluable in tumors from 1450 patients (97.8%) (746 [51.4%] positive; 704 [48.6%] negative). Country, sex, ethnicity, smoking status, pack-years (all p < 0.001), disease stage (p = 0.009), and histology type (p = 0.016) correlated significantly with EGFR mutation frequency. Mutation frequency was 61.1% in females, 44.0% in males; lower in patients from India (22.2%) compared with other areas (47.2%- 64.2%); highest among neversmokers (60.7%); and decreased as pack-year number increased (>0-10 pack-years, 57.9%; >50 pack-years, 31.4%) (similar trend by sex). Ethnic group (p < 0.001) and packyears (p < 0.001) had statistically significant associations with mutation frequency (multivariate analysis); sex was not significant when adjusted for smoking status. The authors conclude that there is high EGFR mutation frequency (51.4% overall) in tumors from Asian patients with adenocarcinoma. J Thorac Oncol. February 2014. PMID: 24419411.
