Stereotactic Radiosurgery in Treating Patients With Stage I or Stage II Non-Small Cell Lung Cancer

OBJECTIVES: * To establish the maximum tolerated dose of CyberKnife® hypofractionated stereotactic radiosurgery in patients with medically inoperable, stage I or II non-small cell lung cancer. * To establish the relationship between positron emission tomography (PET) response and local control and survival using fludeoxyglucose F 18 PET/CT imaging before treatment and at 1, 3, 6, and 12 months after treatment. OUTLINE: Patients undergo placement of 3 gold fiducial markers by CT-guidance or bronchoscopy. Patients then undergo CyberKnife® hypofractionated stereotactic radiosurgery over 45-120 minutes twice weekly for 2 weeks. Patients undergo fludeoxyglucose F 18 PET/CT scan at baseline and at 1, 3, 6, and 12 months after completion of treatment. After completion of study treatment, patients are followed periodically for up to 4 years.