Because of the demonstrated single agent activity and excellent tolerability in patients with refractory non-small cell lung cancer, ZD1839 may be of benefit in the first-line treatment of patients with advanced non-small cell lung cancer who have poor performance status. In this phase II trial, we will investigate the single agent activity of first-line ZD1839 in patients with advanced non-small cell lung cancer with poor performance status

Upon determination of eligibility, patients will be receive:

• ZD1839

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.