Epidermal Growth Factor Receptor Mutations in the Blood of Patients With Advanced Non-Small Cell Lung Cancer

OBJECTIVES: * Determine if epidermal growth factor receptor (EGFR) mutation exists in the peripheral blood of patients with advanced non-small cell lung cancer (NSCLC). * Estimate the frequency of EGFR mutation in these patients. * Correlate the presence of EGFR mutation in blood with EGFR mutation in primary or metastatic NSCLC tumor block. OUTLINE: Patients undergo blood collection for analysis of epidermal growth factor receptor mutation by DNA sequencing. PROJECTED ACCRUAL: A total of 50 patients will be accrued for this study.