Data recently published in JAMA Oncology suggests individualized stereotactic ablative radiotherapy used to treat lung tumors may allow minimization of treatment dose, resulting in excellent tumor control among patients with lung cancer. Michael F. Gensheimer, MD, and colleagues conducted a phase 2, multicenter, nonrandomized controlled trial to assess the impact of individualizing lung stereotactic ablative body radiotherapy (SABR) dose and fractionation by tumor size. The study team divided patients into cohorts to cancer type: initial diagnosis of non-small cell lung cancer (NSCLC) with an American Joint Committee on Cancer 7th edition T1-3N0M0 tumor, a T1-3N0M0 new primary NSCLC with a history of prior NSCLC or multiple NSCLCs, or lung metastases from NSCLC or another solid tumor. The study enrolled 217 patients in 240 treatment courses and treated 285 tumors. At one year, freedom from local recurrence at 1 year was 97% (90% CI, 91%-99%) for group 1, 94% (90% CI, 87%-97%) for group 2, and 96% (90% CI, 89%- 98%) for group 3. Freedom from local recurrence at 5 years ranged from 83% to 93% among the cohorts. The proportion of patients with grade 3 to 5 toxic effects was low, at 5%.