Multicenter, randomized phase 2 trial of one versus three fractions of SBRT for peripheral stage I-II non-small cell lung cancer: long-term outcomes

Stereotactic body radiation therapy (SBRT) is standard of care for inoperable early-stage non-small cell lung cancer. A multicenter, randomized phase 2 trial in the USA compared 30 Gy in 1 fraction (arm 1) versus 60 Gy in 3 fractions (arm 2) for medically inoperable patients with peripheral clinical T1-T2/N0M0 NSCLC. Patients were stratified by performance status and randomized to arm 1 or arm 2. Between September 2008 and April 2015, 98 patients were randomized. Long-term outcomes have now been published The primary endpoint was thoracic grade 3 or higher adverse events (AE) per CTCAE. Median survival was 40.3 months. There were no new attributable AEs within the additional follow-up period. There were no significant differences between the arms for the secondary outcomes freedom from local failure, freedom from distal failure, progression-free survival, or overall survival. The authors conclude that the study demonstrated that 30 Gy in 1 fraction was equivalent to 60 Gy in 3 fractions in terms of toxicity and oncological outcomes.