The results of fastact2 show that chemotherapy plus erlotinib significantly prolonged PFS and OS of patients with NSCLC. However, outcome of the combination therapy are similar to those reported in several trials of single-agent EGFR TKIs. So which is the optimal first-line treatment for patients who harbored a sensitive EGFR mutation? The investigators need a head-to-head study to reply.

Inclusion Criteria:

1. Signed informed consent
2. Age >=18 years
3. Histologically documented, unresectable, inoperable, locally advanced, recurrent or metastatic Stage IV Non-Small Cell Lung Cancer (NSCLC)
4. A cytologic diagnosis is acceptable (i.e., FNA or pleural fluid cytology)
5. Measurable or non-measurable disease
6. Able to comply with study and follow-up procedures

Exclusion Criteria:

• Evidence of small cell, carcinoid, or mixed small cell/non-small cell histology
• Malignancies within 3 years except for adequately treated carcinoma in situ of -the cervix or basal or squamous cell skin cancer
• Symptomatic or untreated brain metastases
• Prior systemic chemotherapy for NSCLC
• Unstable systemic disease, including active infection, uncontrolled hypertension, unstable angina, congestive heart failure, or myocardial infarction within 6 months prior to Day 1, or serious cardiac arrhythmia requiring medication (patients with chronic atrial arrhythmia, i.e., atrial fibrillation or paroxysmal supraventricular tachycardia, are eligible)
• History of other diseases, metabolic dysfunction, physical examination finding, or clinical laboratory finding giving reasonable suspicion of a disease or condition that contraindicates the use of an investigational drug or that might affect the interpretation of the results of the study or render the patient at high risk from treatment complications
• Gastrointestinal tract disease resulting in an inability to take oral medication or a requirement for intravenous (IV) alimentation, or prior surgical procedures affecting absorption
• Pregnancy or lactation