Study of Concurrent Pemetrexed, Cisplatin and Radiotherapy in Local Advanced Non-Small Cell Lung Cancer

Inclusion Criteria: * Age ≧18 years. * Performance status of 0 to 1 on the Eastern Cooperative Oncology Group (ECOG) Scale. * Patients with histologically or cytological-proven non-small cell lung cancer. * Stage IIIA or IIIB, excluding those with pericardial, pleural effusion, and those with contralateral hilar or contralateral supraclavicular lymph nodes. * Patients must have measurable disease according to RECIST criteria, and all detectable tumor can be encompassed by radiation therapy fields. * Weight loss ≦ 5% in the previous six months. * Patient must have adequate blood, liver, lungs and kidney function within the requirements of this study. * Female patients of child-bearing potential must test negative for pregnancy at the time of enrollment based on a serum pregnancy test. Male and female patients must agree to use a reliable method of birth control during and for 3 months following the last dose of study drug. * Patients must sign a study-specific informed consent form prior to study entry. Exclusion Criteria: * Undifferentiated small cell carcinoma, any stage. * Complete tumor resection, recurrent disease, or those patients eligible for definitive surgery. * Stage IV. * Age \<18 years. * Performance status ≧2 on the Eastern Cooperative Oncology Group (ECOG) Scale. * Previous chemotherapy or previous biologic response modifiers for current lung cancer. * Patient has previously had thoracic radiation therapy. * Have received treatment within the last 30 days with a drug that has not received regulatory approval for any indication at the time of study entry. * Prior or concurrent malignancy except non-melanomatous skin cancer unless disease-free for five years or more. * Serious concomitant disorders that would compromise the safety of the patient, or compromise the patient's ability to complete the study, at the discretion of the investigator. * History of significant neurological or mental disorder, including seizures or dementia. * Inability to interrupt aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs) 2 days before, the day of, and 2 days after the dose of pemetrexed. If a patient is taking an NSAID (Cox-2 inhibitors included) or salicylate with a long half-life (e.g. naproxen, piroxicam, diflusinal, nabumetone, rofecoxib, or celecoxib) it should not be taken 5 days before, the day of, and 2 days after the dose of pemetrexed. * Inability or unwillingness to take folic acid, vitamin B12 supplementation, or dexamethasone. * Pregnant or lactating females.