Purpose: This prospective trial was conducted to evaluate the role of gefitinib in never-smokers with advanced or metastatic adenocarcinoma of the lung.
Patients and methods: The main inclusion criteria were stage IIIB/IV adenocarcinoma of the lung and status as a lifetime never-smoker. Patients received a 250-mg single oral daily dose of gefitinib until disease progression, unacceptable toxicity, or patient's refusal. Tumor response was assessed after every two 4-week cycles according to the World Health Organization response criteria. Additional analyses were performed to identify predictors of response and survival.
Results: Between August 2003 and March 2005, 72 Korean patients were enrolled; 55 chemotherapy naive, 17 previously treated; 6 male, 66 female; and ECOG PS 0/1/2, 24/42/4. All patients were assessed for response, toxicity, quality of life, and survival. Overall objective tumor response rate was 55.6% (95% confidence interval [CI], 43.4-67.3%). With a median follow-up of 23 months, the median survival time was 19.7 months (95% CI, 18.5-21.0 months) with a 1-year survival rate of 76.3%. The median duration of response was 6.8 months (95% CI, 4.7-9.0 months). Therapy-related improvement of symptoms and quality of life was observed within 2 to 4 weeks after the commencement of therapy in the responders. In a multivariate Cox proportional hazard model, good performance status and no prior history of chemotherapy were the two significant predictors of better survival (p = 0.005 and 0.042).
Conclusion: Gefitinib showed very promising antitumor activity and survival outcome in Korean never-smokers with adenocarcinoma of the lung. It seems to be a good alternative to standard chemotherapy as a first-line therapy for this subgroup.