Phase III clinical trial - Appareil pulmonaire

RATIONALE: Specialized radiation therapy that delivers a high dose of radiation directly to the tumor may kill more tumor cells and cause less damage to normal tissue. Giving radiation therapy after surgery may kill any tumor cells that remain after surgery. It is not yet known whether giving radiation therapy after surgery is more effective than no radiation therapy in treating patients with non-small cell lung cancer.;PURPOSE: This randomized phase III trial is studying radiation therapy to see how well it works compared to no radiation therapy in treating patients with non-small cell lung cancer that has been completely removed by surgery.