Chemotherapy or Observation in Treating Patients With Early Stage Non-Small Cell Lung Cancer

RATIONALE: Drugs used in chemotherapy, such as vinorelbine, cisplatin, docetaxel, gemcitabine, and pemetrexed disodium, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Sometimes after surgery, the tumor may not need more treatment until it progresses. In this case, observation may be sufficient. It is not yet known whether chemotherapy is more effective than observation in treating patients who have undergone surgery for stage I non-small cell lung cancer. PURPOSE: This randomized phase III trial is studying four chemotherapy regimens to see how well they work compared with observation in treating patients with early stage non-small cell lung cancer.