Gemcitabine Plus Radiation Therapy or Combination Chemotherapy in Treating Patients With Non-small Cell Lung Cancer

OBJECTIVES: * Determine the maximum tolerated dose of twice-weekly gemcitabine when delivered concurrently with thoracic radiotherapy alone or following 2 cycles of induction chemotherapy in patients with Stage IIIA or IIIB non-small cell lung cancer. * Assess the toxicity of concurrent thoracic radiation and gemcitabine in these patients. * Determine the effectiveness of concurrent radiation and gemcitabine by determining the complete response rate, partial response rate, time to recurrence, pattern of recurrence, and overall survival in a cohort of these patients. OUTLINE: This is an alternating two arm, dose escalation, multicenter study. Arm I: Patients receive twice-weekly gemcitabine as a 30 minute infusion. Concurrent radiation therapy is administered 5 days a week for 6 weeks. Arm II: Patients receive 2 cycles of induction chemotherapy consisting of gemcitabine as a 30 minute infusion on day 1 and 8 and cisplatin IV over 1 hour on day 1. Each cycle is 21 days. Patients then receive gemcitabine and radiation therapy as in arm I. Cohorts of 3 patients are enrolled into each treatment arm at each dose level of gemcitabine. Toxicity for each arm is assessed independently. Once dose limiting toxicity (DLT) is observed at any dose level, 3 more patients are enrolled at the same dose level. The maximum tolerated dose (MTD) is defined as the dose at which no more than 1 of 6 patients experiences grade 4 toxicity, or no more than 4 of 6 patients experience grade 3 or worse toxicity (DLT). After the MTD is determined for each treatment arm, additional patients are treated at that dose level for the phase II portion of the study. Patients are followed every 3 months for 2 years, then every 4 months for the next 2 years, and then every 6 months thereafter. PROJECTED ACCRUAL: There will be approximately 24-48 patients accrued into this study within 1-2 years.