Inclusion Criteria:

• IIIA :

Histologic or cytologic diagnosis of ipsilateral mediastinal lymph node involvement, or Tumors greater than 7 cm or with chest wall invasion, or involvement of one of the following diaphragm, phrenic nerve, mediastinal pleura or parietal pericardium with hilar or mediastinal lymph node involvement.

More than one mediastinal lymph node enlarged on CT scan and the same lymph nodes positive on PET scans or Paralyzed left vocal cord with separate lung primary distinct from the aorto-pulmonary lymph nodes on the CT scan.

Evidence of tumor extension into the mediastinum and/or mediastinal structures either at the time of mediastinoscopy, bronchoscopy or on CT scans.

• IIIB:

Histologic or cytologic diagnosis of N3 lymph node involvement; or Enlarged N3 lymph nodes on CT scan that are positive on PET scan as well. Patient must not have extension of lymph node involvement to cervical lymph nodes other than supraclavicular lymph nodes; or Right sided primary with left vocal cord paralysis; or Patients with a nodules in the same lung but no other areas of involvement. Patients with prior surgically resected stage I NSCLC who did not receive any adjuvant therapy, who now have stage IIIA or B NSCLC will be eligible.

• Age ≥ 18 years
• SWOG performance status 0 or 1 (see Appendix)
• Adequate organ function as evidenced by Absolute neutrophil count of ≥ 1.5 x 10(9)/L, Platelet count ≥ 100,000 x 109/L Serum creatinine ≤ 1.5 times the institutional upper limit of normal (ULN), Calculated creatinine clearance (Cockcroft-Gault formula) of ≥ 45mL/min, Serum bilirubin ≤ ULN, Transaminases (SGOT and/or SGPT) ≤ 1.5 times institutional ULN and alkaline phosphatase ≤ 2.5 times ULN, FEV1 of ≥ 1 liter and DLCO > 50% of predicted.
• Patient should undergo brain imaging (CT scan or MRI) to rule out brain metastases.
• Signed informed consent that details the investigational nature of the study according to institutional and federal guidelines.
• Registered with Clinical Trials Office at Karmanos Cancer Institute/Wayne State University.

Exclusion Criteria:

• Prior chemotherapy, radiation for any malignancy in which they received any thoracic radiotherapy.
• Patients with concurrent malignancy. Patients with prior or concurrent malignancy will be allowed as long as the treating physician considers it unlikely to impact the clinical outcome of the patient.
• Patients with peripheral neuropathy ≥ 2.
• Serious medical illness including but not limited to uncontrolled congestive heart failure, uncontrolled angina, myocardial infarction or cerebrovascular event with 6 months of registration, history of chronic active hepatitis or history of HIV or an active bacterial infection will not be eligible.
• Inability or unwillingness to take folic acid or Vitamin B12 or dexamethasone.
• Pregnant or lactating women. All pre-menopausal and peri-menopausal women should have a urine test for pregnancy within a week of starting therapy. All patients of child bearing potential should agree to use an effective contraceptive method.
• Patients should not participate in any other therapeutic investigational study while taking part in this study.