Inclusion Criteria:  Stage I-II NSCLC Adequate diagnostic biopsy tissue to allow pre-SBRT tumor analysis Candidate for oncologic surgery (lobectomy or sub lobar resection) for the lung cancer Lesion located peripherally, ≥ 2 cm from bronchial margin, and 1 cm from visceral pleura, with location deemed acceptable by cardio-thoracic surgeon for resection. Adequate pulmonary function test results  Exclusion Criteria:  Prior history of lung/chest wall surgery Prior chest radiation Prior immunotherapy History of autoimmune disease Currently using immunosuppressive drugs