SABR vs. Limited Resection for Non-small Cell Lung Cancer: Are We Closer to an Answer?

Lobectomy is currently the guideline-recognized gold standard for the treatment of early-stage non-small cell lung cancer (ES-NSCLC) in patients who are surgical candidates. In patients who are not medically fit for surgery, stereotactic ablative radiotherapy (SABR) is the treatment of choice with good reported rates of local control and overall survival. For patients at high risk for lobectomy, sublobar resection (SLR) may achieve similar outcomes as lobectomy, especially for peripheral tumors <= 2 cm. While there are merits to both SLR and SABR for these high-risk patients, evidence is conflicting on which may be preferred in the context of clinical and cost-effectiveness outcomes. For SABR, a histologic diagnosis is preferred prior to treatment. However, some individuals may be at high risk for biopsy, and a likelihood-of-malignancy probability threshold of >85 % has been proposed as reasonable to proceed with SABR in a positron emission tomography (PET)-positive lesion without histology. Increased risks of SABR are noted in ultra-central tumors and in patients recently treated with anti-VEGF therapy. Co-existing interstitial lung disease can cause increased treatment-related toxicity in both SABR and surgery. Toxicity is generally well tolerated for SABR and SLR, though treatment-related mortality may be higher in surgery. Ongoing comparative effectiveness research, especially through randomized control trials, is crucial in further delineating the roles of SLR and SABR in the treatment of ES-NSCLC.