Positron Emission Tomography in Predicting Response in Patients Who Are Undergoing Treatment With Pemetrexed Disodium and Cisplatin With or Without Surgery for Stage I, Stage II, or Stage III Non-Small Cell Lung Cancer

DISEASE CHARACTERISTICS: * Histologically or cytologically confirmed non-small cell lung cancer (NSCLC) * Stage IB, II, IIIA, or IIIB (T4, N0-1) disease * Staging must have been performed 4 weeks prior to study entry with a CT scan of chest, upper abdomen, and fludeoxyglucose F 18 (\^18FDG) positron emission tomography (PET) scan * Mediastinal evaluation and staging based on combination of CT scan and FDG-PET results * If N1 or N2 nodes are found by FDG-PET or CT scan, metastases must be ruled out by brain MRI * Measurable and resectable disease * T4 lesions must be resectable * Eligible for curative surgery * No malignant pleural effusion PATIENT CHARACTERISTICS: Age * 18 and over Performance status * ECOG 0-1 Life expectancy * Not specified Hematopoietic * Absolute neutrophil count ≥ 1,250/mm\^3 * Platelet count ≥ 100,000/mm\^3 Hepatic * Bilirubin ≤ 1.5 times upper limit of normal (ULN) * AST and ALT ≤ 3.0 times ULN Renal * Creatinine clearance ≥ 45 mL/min Pulmonary * Adequate pulmonary reserve to undergo surgery * Predicted FEV\_1 \> 0.8 L after resection Other * Not pregnant or nursing * Negative pregnancy test * Fertile patients must use effective contraception during and for 3 months after completion of study treatment * Able to take corticosteroids * Able to take folic acid or vitamin B\_12 supplements * No other malignancy within the past 5 years except nonmelanoma skin cancer or noninvasive cervical cancer * No concurrent serious or uncontrolled disorder that would preclude study participation * No type I diabetes mellitus * Type II diabetes mellitus allowed if glucose is 80-150 mg/dL PRIOR CONCURRENT THERAPY: Biologic therapy * No concurrent immunotherapy * No concurrent prophylactic filgrastim (G-CSF) * No concurrent thrombopoiesis-stimulating agents Chemotherapy * At least 5 years since prior chemotherapy Endocrine therapy * No concurrent anticancer hormonal therapy Radiotherapy * No prior radiotherapy to the chest * No concurrent curative or palliative radiotherapy Surgery * Not specified Other * At least 30 days since prior non-FDA-approved or investigational agents * At least 5 days since prior aspirin or other nonsteroidal anti-inflammatory agents (8 days for long-acting agents \[e.g., piroxicam\]) * No other concurrent anticancer therapy * No other concurrent investigational agents