EGFR mutations in patients with non small-cell lung cancer in Bulgaria and treatment with gefitinib.

PURPOSE: To evaluate the EGFR mutations in non small cell lung cancer (NSCLC) patients in Bulgaria, as well as to summarize the outcomes of patients with EGFR mutations, treated with gefitinib as first- or subsequent-line therapy. METHODS: From January 2010 to March 2012 tumor samples from773 NSCLC patients were evaluated for EGFR mutations. RESULTS: Seventy-one mutations were found and 34 patients were treated with gefitinib. Complete remission (CR) was achieved in 2 patients (6.9%), partial remission (PR) in 11 (37.9%), stable disease (SD) in 13 (44.8%), and disease progression (PD) in 3 (10.3%). Higher objective response rate was seen in women and in never-smokers.The mean progression-free survival (PFS) was 11.1 months (95% CI 9.1-13.1), registered in 29 patients (median PFS 10 months ; 95% CI 8.9-11.1).Tolerability to gefitinib was acceptable, with prevalence of skin toxicity, and it did not lead to any significant decline of the patients' quality of life. CONCLUSION: This is the first study in Bulgaria to evaluate EGFR mutations in NSCLC patients,which were encountered in 9.4% of the studied population. The present study confirms the benefits of first- and subsequent-lines of gefitinib for the treatment of this patient group. Our data give grounds for the conclusion that gefitinib is an effective and well-tolerated therapeutic option for patients with locally advanced and metastatic NSCLC harboring EGFR mutations.