Objective: To investigate the efficacy, time to progression, survival time and toxicity of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor Gefitinib (Iressa), a target therapy agent, in the treatment of advanced non-small cell lung cancer (NSCLC), and to analyze the factors affecting the efficacy and patients' survival.
Methods: From Nov. 2003 to May 2005, 91 patients with advanced NSCLC who failed from previous first-line chemotherapy were treated by gefitinib in this trial with a median chemotherapy cycle of six. Sixty-eight of these 91 patients (74.7%) had received a second-line chemotherapy. Seventy-six (83.5%) of the 91 patients had stage IV disease, and 42 (46.2%) had developed metastases at least two sites. Gefitinib was administered orally at a dose of 250 mg daily until disease progressed or severe toxicity developed. Clinical data were analyzed using chi-square test, Log-lank test, Cox regression and Kaplan-Meier survival analysis in SPSS 11.5.
Results: (1) Overall response rate was 20.9% (19/91) and the disease control rate (response and stable disease) was 63.7% (58/91). Patients'symptoms were improved in 72.7% (40/55), and ECOG score was improved or remained stable in 71.4% (65/91). The disease control rate of those who had adenocarcinoma, or received second-line chemotherapy or developed skin toxicity was significantly better than the other patients (P value = 0.04, 0.02, 0.00, respectively). (2) Median time to progress (TIP) was 5.0 months (95% CI 3.26-6.74). (3) Median following-up duration was 7.5 months (1-18. 5 months), and 1-year survival rate was 56.4%. Of the 56 patients (61.5%) who were still alive when following-up ended, 29 (51.8%) had stable disease, 20 had survived more than one year (12-18. 5 months). Non-smoker, stable diseases, skin toxicities, and controlled metastatic diseases during the treatment of gefitinib were the favorable factors affecting the survival (P value = 0.00, 0.00, 0.00, 0.01, respectively). (4) The main toxicity of gefitinib was grade I or II skin toxicity.
Conclusion: Gefitinib, a target therapy agent which may be an alternative, is effective and tolerable in the treatment for advanced NSCLC patients who have failed in the first-line or even second-line chemotherapy. It can remarkablely improve the disease control rate and disease-related symptoms, and also prolong survival in the responders.