Carboplatin and Gemcitabine Combined With Celecoxib and/or Zileuton in Treating Patients With Advanced Non-Small Cell Lung Cancer

RATIONALE: Drugs used in chemotherapy, such as carboplatin and gemcitabine, work in different ways to stop tumor cells from dividing so they stop growing or die. Celecoxib and zileuton may stop the growth of tumor cells by stopping blood flow to the tumor and may block the enzymes necessary for tumor cell growth. Combining chemotherapy with celecoxib and/or zileuton may kill more tumor cells. PURPOSE: Randomized phase II trial to study the effectiveness of combining celecoxib and/or zileuton with carboplatin and gemcitabine in treating patients who have advanced non-small cell lung cancer.