Assess the Efficacy, Safety and Tolerability of Gefitinib (Iressa® 250mg) as Maintenance Therapy in Locally Advanced or Metastatic (Stage IIIB/IV) Non Small Cell Lung Cancer (NSCLC) - INFORM

Exclusion Criteria

• - Prior exposure to monoclonal antibodies or small molecule inhibitors against EGFR receptors. (e.g. gefitinib, erlotinib, C225)
• - Patients with previously diagnosed and treated CNS metastases or spinal cord compression may be considered if they are clinically stable and have been discontinued from steroid therapy for at least 4 weeks prior to first dose of study medication.
• - Any evidence of clinically active interstitial lung disease (patients with chronic, stable, radiographic changes who are asymptomatic need not be excluded)
• - Known biomarker status of one or more of the following: Tumour EGFR gene copy number, tumour EGFR gene mutation status, tumour EGFR protein expression.