Pemetrexed Disodium and Cisplatin Before or After Surgery in Treating Patients With Stage IB or Stage II Non-Small Cell Lung Cancer That Can be Removed by Surgery

RATIONALE: Drugs used in chemotherapy, such as pemetrexed disodium and cisplatin, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Giving more than one drug (combination chemotherapy) before surgery may make the tumor smaller and reduce the amount of normal tissue that needs to be removed. Giving combination chemotherapy after surgery may kill any tumor cells that remain after surgery. It is not yet known whether combination chemotherapy is more effective before or after surgery in treating non-small cell lung cancer. PURPOSE: This randomized phase II trial is studying the side effects of pemetrexed disodium and cisplatin and comparing how well they work when given before or after surgery in treating patients with stage IB or stage II non-small cell lung cancer that can be removed by surgery.