Induction Chemotherapy Using Paclitaxel, Carboplatin, CPT-11 With Pegfilgrastim

Patients enrolled on this study will have been diagnosed with non-small cell lung cancer which cannot be removed by an operation. The standard treatment for this disease is a combination of chemotherapy and radiation therapy; however, the best way to combine these treatments is not known. This study will examine if the combination of chemotherapy and radiotherapy has an increased effect on slowing tumor growth with the addition of a drug called ZD1839. In this study, chemotherapy will be given initially (induction therapy) to try to control the spread of the cancer. Then radiation and chemotherapy will be given together. Receiving chemotherapy at the same time as radiation treatments can enhance the effect of the radiation. In this study, patients will receive a drug called ZD1839. In laboratory tests on cancer cells, ZD1839 has shown an additive effect when used in combination with radiation. ZD1839 has also been shown to slow or stop growth in tumors. The purpose of this study is to determine the side effects and effectiveness of using ZD1839 when used with radiation in this treatment regimen (induction chemotherapy followed by combination chemotherapy, ZD1839, and radiation therapy).