• Lung tumors will be ≤ 5 cm and centrally located, meaning any portion of gross tumor volume located within 2 cm of (but not abutting) the proximal bronchial tree (trachea, carina, right and left main bronchi, right and left upper lobe bronchi, bronchus intermedius, right middle lobe bronchus, lingular bronchus, right and left lower lobe bronchi), or within 2 cm of (whether abutting or not) major vessels, esophagus, or heart (based on RTOG and MD Anderson Cancer Center definitions 33,34). Multiple concurrent isocenters are allowed if at least one tumor meets the above criteria, and if all dose constraints for the plan summation can be met. These concurrent tumors other than study target lesion can be treated as per SOC and does not necessarily have to meet the above size limit. The PI will review and prospectively approve any lesions abutting these organs.

• ECOG Performance Status of 0-2

• Age \> 18

• Patients must sign a study-specific consent form.