Patterns of Progression and Feasibility of Re-biopsy After First-line Erlotinib for Advanced EGFR Mutation-positive Non-small-cell Lung Cancer

AIM: To assess the patterns of disease progression in advanced/metastatic epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancer (NSCLC) on first-line treatment with erlotinib and identify potential prognostic factors for progression-free survival (PFS). PATIENTS AND METHODS: Patients with stage IIIB/IV EGFR-mutation-positive NSCLC receiving first-line erlotinib were followed-up until 24 months after the last patient was enrolled or until premature withdrawal for any cause. RESULTS: A total of 127 evaluable patients were enrolled. The median PFS and overall survival were 8.8 and 19.1 months, respectively. Disease progression was asymptomatic in 57.6% of patients and 53.3% developed new sites of metastasis. The presence of liver metastasis was identified as an independent prognostic factor for poor PFS. CONCLUSION: Metastatic progression with asymptomatic disease seems to be the predominant pattern of disease progression on first-line erlotinib in real-life practice in patients with advanced/metastatic EGFR-mutant NSCLC. Additionally, the presence of liver metastases may negatively affect PFS in these patients.