Gemcitabine Plus Oxaliplatin in Advanced Stage IIIB/IV Non Small Cell Lung Cancer (NSCLC)

Inclusion Criteria: 1. Histologic or cytologic diagnosis of NSCLC, Stage IV or selected stage IIIB (with positive pleural effusion or separate tumor nodules in the same lobe) according to the American Joint Committee on Cancer (AJCC). 2. No prior chemotherapy. 3. Prior radiation therapy is allowed as long as the irradiated area is not the only source of measurable disease. 4. No other forms of cancer therapy, such as radiation, immunotherapy for at least 4 weeks before the enrollment in study. 5. Performance status of 0, 1, 2 on the ECOG criteria. 6. At least one unidimensional measurable lesion meeting Response Evaluation Criteria in Solid Tumors (RECIST. 2000). 7. Estimated life expectancy of at least 12 weeks. 8. Patient compliance that allow adequate follow-up. 9. Adequate organ function including the following:Adequate hematologic function: WBC count ≥ 3,500/uL, absolute neutrophil count (ANC) ≥ 1,500/uL, and platelet count ≥ 100,000/uLAdequate hepatic function: bilirubin ≤ 1.5 x UNL, ALT or AST ≤ 2.5 x UNL.Adequate renal function: creatinine ≤ 1.5mg/dL. 10. Informed consent from patient 11. Males or females at least 18 years old. 12. If female: childbearing potential either terminated by surgery, radiation, or menopause, or attenuated by use of an approved contraceptive method (intrauterine device \[IUD\], birth control pills, or barrier device) during and for 3 months after trial. If male, use of an approved contraceptive method during the study and 3 months afterwards. Females with childbearing potential must have a urine negative hCG test within 7 days prior to the study registration. Exclusion Criteria: 1. MI within preceding 6 months or symptomatic heart disease, including unstable angina, congestive heart failure or uncontrolled arrhythmia 2. Serious concomitant infection including post obstructive pneumonia 3. Second primary malignancy (except in situ carcinoma of the cervix or adequately treated basal cell carcinoma of the skin or prior malignancy treated more than 5 years ago without recurrence) 4. Pregnant or nursing women 5. Psychiatric disorder that would preclude compliance. 6. Major surgery other than biopsy within the past two weeks.