Lung Cancer STARS Trial - STARS Revised Clinical Trial Protocol: Stereotactic Ablative Radiotherapy (SABR) in Stage I Non-small Cell Lung Cancer Patients Who Can Undergo Lobectomy

Inclusion Criteria: 1. Histological confirmation of non-small cell cancer will be required by either biopsy or cytology. The following primary cancer types are eligible: squamous cell carcinoma, adenocarcinoma with or without BAC features, large cell carcinoma with or without neuroendocrine features, neuroendocrine carcinoma, bronchioloalveolar cell carcinoma, or non-small cell carcinoma not otherwise specified. 2. Eligible patients must have appropriate staging studies identifying them as specific subsets of the revised IASLC stage IA based on the following combination of TNM staging: T1a,N0,M0 or T1b,N0,M0 3. A PET/CT scan is required. Patients with hilar or mediastinal lymph nodes with short axis diameter \</= 1cm and no abnormal hilar or mediastinal uptake on PET will be considered N0. Patients with \> 1 cm short axis diameter of hilar or mediastinal lymph nodes on CT or abnormal PET (including suspicious but non-diagnostic uptake) may still be eligible if directed tissue biopsy of all abnormally identified areas are negative for cancer. Solitary pulmonary lesions \</= 6mm will not be considered significant. 4. Patients must be considered a candidate for surgical resection of the primary tumor. Standard justification for deeming a patient medically operable based on pulmonary function for surgical resection of NSCLC may include any of the following: Baseline FEV1 \> 40% predicted, post-operative predicted FEV1 \> 30% predicted, diffusion capacity \> 40% predicted, absent baseline hypoxemia and/or hypercapnia, exercise oxygen consumption \> 50% predicted, absent severe pulmonary hypertension, absent severe cerebral, cardiac, or peripheral vascular disease, and absent severe chronic heart disease. 5. Patients must be \>/= 18 years of age. 6. The patient's Zubrod performance status must be Zubrod 0-2. 7. PET/CT scan to include both lungs, the mediastinum, and adrenal glands; Primary tumor dimension will be measured on diagnostic CT and again on simulation CT. Must be done within 10 weeks prior to study entry. 8. Mediastinoscopy or endobronchial ultrasound (EBUS) guided biopsy of mediastinal lymph nodes is required for all patients. Must be done within 10 weeks of study entry. 9. MRI or CT scans of Brain if there are symptoms or signs suggesting brain metastases, must be done within 10 weeks prior to study entry. 10. Invasive Mediastinal Staging - All patients with CT and/or PET evidence of hilar (level 10) or mediastinal lymph nodes \> 1.0 cm in the shortest diameter must be staged by either cervical mediastinoscopy, esophageal endoscopic ultrasound guided biopsy, or endobronchial ultrasound guided biopsy. 11. Patients must sign a study-specific consent form. 12. Patients (men and women) of child bearing potential should use an effective (for them) method of birth control throughout their participation in this study. Exclusion Criteria: 1. Patients with primary tumors \> 3 cm. 2. Patients with well-differentiated neuroendocrine carcinoma (carcinoid tumor). 3. Direct evidence of regional or distant metastases after appropriate staging studies, or synchronous primary or prior malignancy in the past 3 years other than nonmelanomatous skin cancer or in situ cancer. 4. Previous lung or mediastinal radiotherapy. 5. Plans for the patient to receive other concomitant local therapy (including standard fractionated radiotherapy and surgery) while on this protocol except at disease progression. 6. Pregnant or lactating women, as treatment involves unforeseeable risks to the embryo or fetus. 7. Cannot achieve acceptable SABR planning to meet minimal requirement of target coverage and dose-volume constraints of critical structures (see RT techniques).