FDG-Labeled PET Scan in Planning Chemotherapy in Treating Patients With Stage IIIB or IV Non-Small Cell Lung Cancer

PRIMARY OBJECTIVES: I. Assess the response rate in patients who do not demonstrate an early response to carboplatin/paclitaxel as determined by FDG-PET ("initial non-responders") who are subsequently treated with three additional courses of docetaxel/gemcitabine. SECONDARY OBJECTIVES: I. Evaluate the ability of FDG-PET to predict response to therapy as measured by computed tomography (CT). II. Evaluate the early and late changes in tumor FDG uptake (change in standardized uptake value \[SUV\]) in all patients and correlate with overall survival (OS). OUTLINE: All patients receive paclitaxel intravenously (IV) over 3 hours and carboplatin IV over 30 minutes on day 1. Patients undergo FDG-PET/CT scan between days 18-21. Patients are then assigned to 1 of 2 treatment groups. GROUP I (Responders): Patients receive paclitaxel IV over 3 hours and carboplatin IV over 30 minutes on day 1. Treatment repeats every 3 weeks for up to 3 additional courses in the absence of disease progression or unacceptable toxicity. GROUP II (Initial non-responders): Patients receive gemcitabine hydrochloride IV over 30 minutes on days 1 and 8 and docetaxel IV over 1 hour on day 8. Treatment repeats every 3 weeks for up to 3 courses in the absence of disease progression or unacceptable toxicity. Patients undergo FDG-PET/CT scan between days 18-21 of course 2. After completion of study treatment, patients are followed up at days 81-84 and then periodically thereafter.