Erlotinib and SBRT in Treating Patients With Locally Advanced or Metastatic Non-Small Cell Lung Cancer

Inclusion Criteria Patients must meet all of the following inclusion criteria to be eligible for participation in this study: 1. Patients must have biopsy proven NSCLC that is locally advanced or metastatic. 2. Patients must have had failure of at least one prior chemotherapy regimen. 3. Patients must not have started erlotinib therapy more than 4 weeks prior to the initiation of SBRT. 4. Age ≥ 18 years 5. Patients must have measurable disease at baseline. 6. Patients can have up to only 6 discrete active extracranial lesions (≤3 in the liver and ≤3 in the lung) identified by PET scan and also seen on correlative plain film, CT scan, or MRI within 8 weeks prior to the initiation of SBRT. 1. For patients who have received prior radiotherapy to the primary site in the lung, residual PET activity is difficult to interpret and will not be considered a site of active disease if the CT appearance is stable or improved over an interval of at least three months 2. Patients who previously received radiotherapy to the primary site will be ineligible if there is CT evidence of disease progression within the past 3 months. 3. Patients with previously un-irradiated primary sites will be potentially eligible, but special considerations apply (section 4.3.2). 4. Up to 2 contiguous vertebral metastases will be considered a single site of disease. 7. Patients must have a KPS \>60 8. AST, ALT \& Alkaline phosphates must be ≤ 2.5X the upper limit of normal. Total bilirubin must be within the limit of normal. 9. Patients should have adequate bone marrow function as defined by peripheral granulocyte count of ≥1500/mm³. 10. Patients should have adequate renal function (serum creatinine ≤1.5 times the ULN). 11. Females of childbearing potential should have a negative pregnancy test. 12. Patients who would be receiving SBRT for lung tumors who are known or suspected by the treating radiation oncologist to have compromised lung function must have a documented forced expiratory volume in 1 second (FEV1) ≥ 1L. 13. Patients must provide verbal and written informed consent to participate in the study. 14. Total bilirubin: within normal institutional limits Exclusion Criteria Patients who meet any of the following exclusion criteria are not to be enrolled in this study. 1. Patients who previously received radiotherapy to the primary site with CT evidence of disease progression at the primary site within 3 months following the initial radiotherapy. 2. Patients with either untreated brain metastases or brain metastases treated within the past three months are ineligible 3. Patients with serious, uncontrolled, concurrent infection(s). 4. Significant weight loss (\>10%) in the prior 3 months. 5. Because the tolerance dose of SBRT to the gastrointestinal tract is not established, patients with metastatic disease invading the esophagus, stomach, intestines, or mesenteric lymph nodes will not be eligible. 6. Patients with cutaneous metastasis of NSCLC. 7. Treatment for other carcinomas within the last five years, except cured non-melanoma skin and treated in-situ cancers. 8. Patients with more than 6 discrete extra-cranial lesions. 9. Participation in any investigational drug study within 4 weeks preceding the start of study treatment. 10. Unwillingness to participate or inability to comply with the protocol for the duration of the study. 11. Patients who are pregnant. Patients with reproductive capability will need to use adequate contraception during the time of participation in the study. 12. Patients who have had prior EGFR inhibitors.