Icotinib Versus First-line Chemotherapy Plus Maintenance Treatment in EGFR Positive Lung Adenocarcinoma Patients

Inclusion Criteria: * Recurrent or progressive Non-Small Cell Lung Cancer stage IV or IIIB patients. * Positive EGFR Mutation. * No previous systemic anticancer therapy. * Measurable lesion according to RECIST with at least one measurable lesion not previously irradiated, unless disease progression has been documented at that site. * Provision of written informed consent. Exclusion Criteria: * Experience of Anti-EGFR(the epidermal growth factor receptor) Monoclonal Antibody or small molecular compounds therapy such as gefitinib, erlotinib or Cetuximab. * Evidence of clinically active Interstitial Lung Diseases (Patients with chronic, stable, radiographic changes who are asymptomatic need not be excluded). * Known severe hypersensitivity to icotinib or any of the excipients of this product. * Evidence of any other significant clinical disorder or laboratory finding that makes it undesirable for the subject to participate in the study.