Gemcitabine Hydrochloride or Pemetrexed Disodium and Carboplatin With or Without Celecoxib in Treating Patients With Advanced Non-Small Cell Lung Cancer

OBJECTIVES: Primary * To confirm the beneficial effect of gemcitabine hydrochloride or pemetrexed disodium in combination with carboplatin with or without celecoxib in patients with advanced non-small cell lung cancer that expresses COX-2. Secondary * To describe the response rate in patients treated with these regimens. * To describe the distribution of progression-free survival (PFS) and overall survival of patients treated with these regimens. * To compare the PFS of patients with COX-2 index ≥ 2 (adjusting for CYP2C9 genotype and celecoxib trough concentrations as covariates) treated with these regimens. * To correlate urinary PGE-M level with COX-2 expression, COX-2 inhibition, and outcome. * To evaluate the association between the -765G/C polymorphism in PTGS2 and COX-2 expression in non-small cell lung cancer specimens. * To characterize a trough plasma celecoxib concentration which will be used as a measure of patient adherence to study treatment and which may be used in future studies for correlations with genotype and pharmacodynamic outcomes. OUTLINE: This is a multicenter study. Patients are stratified according to gender, disease stage (IIIB vs IV), histology (squamous cell carcinoma vs non-squamous cell carcinoma), smoking status (never/former light smoker \[defined as ≤ 10 pack years AND quit ≥ 1 year ago\] vs smoker), and COX-2 expression status (COX-2 index ≥ 4 vs COX-2 index ≥ 2 but \< 4). Patients are randomized to 1 of 2 treatment arms. * Arm I: Patients receive gemcitabine hydrochloride\* IV on days 1 and 8 OR pemetrexed disodium\* IV on day 1. Patients also receive carboplatin IV on day 1 and oral celecoxib twice daily on days 1-21. * Arm II: Patients receive gemcitabine hydrochloride\* OR pemetrexed disodium\* and carboplatin as in arm I. Patients also receive oral placebo twice daily on days 1-21. * NOTE: \*Patients with squamous cell carcinoma receive gemcitabine hydrochloride; patients with non-squamous cell carcinoma receive pemetrexed disodium. In both arms, treatment repeats every 21 days for up to 6 courses in the absence of disease progression or unacceptable toxicity. After completion of 6 courses, patients with responding or stable disease may continue to receive celecoxib or placebo alone in the absence of disease progression or unacceptable toxicity. Patients may undergo blood and urine sample collection periodically for correlative laboratory studies. After completion of study therapy, patients are followed up every 2 months for 2 years and then every 6 months for 3 years.