Adjuvant Gemcitabine Plus Oxaliplatin Versus Gemcitabine Plus Cisplatin for Completely Resected Stage IB/II/IIIA NSCLC

Inclusion Criteria: 1. Histologic diagnosis of non-small cell lung cancer. 2. Presence of pathological stage IB, II or IIIA, according to the American Joint Committee on Cancer (AJCC). 3. Completely resected tumor at NCC hospital. 4. No prior tumor therapy (radiotherapy, chemotherapy, immunotherapy, or any other type of tumor therapy). 5. Performance status of 0-1 on ECOG scale. 6. At least 18 years old 7. Patient compliance that allows adequate follow-up. 8. Adequate organ function including the following:Adequate hematologic function: WBC count ≥ 4,000/uL, absolute neutrophil count (ANC) ≥ 1,500/uL, platelet count ≥ 100,000/uL, and hemoglobin ³ 10 gm/dL.Adequate hepatic function: bilirubin ≤ 1.5 x UNL, ALT or AST ≤ 2.5 x UNL.Adequate renal function: creatinine ≤ 1.5mg/dL. 9. Signed informed consent from patient or legal representative. 10. Patients with reproductive potential must use an approved contraceptive method during and for 3 months after the study. Females with childbearing potential must have a negative urine hCG test within 7 days prior to study enrollment. Exclusion Criteria: 1. Concurrent administration of any other tumor therapy, including radiotherapy, chemotherapy, immunotherapy. 2. Active uncontrolled infection. 3. Serious concomitant disorders that would compromise the safety of patient or compromise the patient's ability to tolerate therapy. 4. Second primary malignancy. 5. Significant neurological or mental disorder. 6. Pregnant or nursing. 7. MI within preceding 6 months or symptomatic heart disease including unstable angina, congestive heart failure, or uncontrolled arrhythmia