Evaluation of Symptoms Improvement in NSCLC Patients With First-Line Therapy of EGFR Tyrosine Kinase Inhibitor

The Secondary Objectives are: 1. To estimate symptom improvement rates at weeks 2 and 12 2. To estimate mean change from baseline in overall QoL scores using the FACT-L instrument and LCS score at Week 2, 4 and 12. 3. To estimate the proportion of patients exhibiting an LCS change of 7 points or more at weeks 2, 4 and 12. 4. Subgroup information of symptom improvement rate, QoL and disease-related symptom scores by gender, smoking status, smoking pattern, WHO performance, number of metastatic sites, female/never smokers and patients with COPD at week 2, week 4 and week 12.