Clinical features of gefitinib-responders with non-small cell lung cancer

Abstract

19136 Background: Although chemotherapy improves survival in advanced NSCLC patients, it appears to have reached a therapeutic plateau and novel approaches are urgently required. Under these circumstances, inhibition of the epidermal growth factor receptor (EGFR) tyrosine kinase has emerged as a therapeutic option in patients with NSCLC. Gefitinib, an oral EGFR tyrosine kinase inhibitor (EGFR- TKI), is a leading agent in this class of novel therapeutic agents. Several predictive factors of gefitinib sensitivity have been well described. However, few studies have investigated the clinical features of gefitinib-responders. In the present study, we reviewed the outcomes of gefitinib-responders treated with gefitinib at our institution. Patients and Methods: We retrospectively evaluated the clinical courses of 31 NSCLC patients between October 2004 and June 2007 who received 250 mg/day gefitinib orally and achieved either a complete or partial response. These patients form the basis of this study. There were 17 women and 14 men. There were 13, 3 and 15 patients with cigarettes-year ≥400, cigarettes-year<400 and never a smoker, respectively. Results: At 6 months, patients who achieved either a complete or partial response all were adenocarcinoma. Favorable efficacy was observed in the primary lesion and metastases to the lung, pleura, peritoneum, pericardium, liver, brain and bone. The brain metastasis was the site of major recurrence. Median period for a patient to have improved symptoms was 15 days. Median progression-free survival (PFS) was 10.0 months, median duration of gefitinib treatment was 13.0 months. Gender and smoking status were not correlated to PFS. Rash and diarrhea were the most common adverse events, which were manageable and reversible. None of patients was withdrawn due to the adverse events. Conclusion: Patients of Asian origin with advanced lung adenocarcinoma patients who were refractory to or intolerant of their most recent chemotherapy regimen, gefitinib at a dosage of 250 mg/day was effective. Gender and smoking status were not correlated to PFS. The results of this study should help to further identify which patients are most likely to benefit from treatment with gefitinib. No significant financial relationships to disclose.