Celecoxib in Treating Patients With Early-Stage Head and Neck Cancer or Non-Small Cell Lung Cancer

RATIONALE: Chemoprevention therapy is the use of certain drugs to try to prevent the development or recurrence of cancer. The use of celecoxib may be an effective way to prevent the recurrence of stage I or stage II head and neck cancer or stage I non-small cell lung cancer. PURPOSE: This randomized phase II trial is studying celecoxib to see how well it works compared to that of a placebo in preventing disease recurrence in patients with stage I or stage II head and neck cancer or stage I non-small cell lung cancer.