Iressa in Poor Performance Status Patients With Previously Untreated Advanced Non-Small Cell Lung Cancer

Inclusion Criteria: To be included in this study, you must meet the following criteria: * Biopsy proven non-small cell lung cancer * Recurrent non-small cell lung cancer after previous surgery or radiation * Advanced disease (stage IIIb or IV) * No previous chemotherapy or biological therapy * Require significant assistance with activities of daily living * Measurable disease * Adequate bone marrow, liver and kidney function * Give written informed consent Exclusion Criteria: You cannot participate in this study if any of the following apply to you: * Brain metastasis * Meningeal metastasis * Other uncontrolled malignancies * Women pregnant or lactating * No measurable disease outside previous radiation therapy field Please note: There are additional inclusion/exclusion criteria. The study center will determine if you meet all of the criteria. If you do not qualify for the trial, study personnel will explain the reasons. If you do qualify, study personnel will explain the trial in detail and answer any questions you may have.