As reported in The Lancet Oncology by Chang et al, long-term results of the single-institution revised STARS trial indicate that overall survival in patients receiving stereotactic ablative radiotherapy (SABR) for operable stage IA non–small cell lung cancer (NSCLC) was noninferior to that in a contemporary institutional cohort of patients receiving video-assisted thoracoscopic surgical lobectomy with mediastinal lymph node dissection (VATS L-MLND).
Study Details
In the revised STARS trial, a cohort of 80 patients undergoing SABR was reaccrued between September 2015 and January 2017 at The University of Texas MD Anderson Cancer Center, with a protocol-specified propensity-matched comparison being performed vs a prospectively registered contemporary institutional cohort of 352 patients who underwent VATS L-MLND. SABR was given at 54 Gy in three fractions for peripheral lesions or 50 Gy in four fractions for central tumors (with a simultaneous integrated boost to gross tumor totaling 60 Gy).
The primary endpoint was 3-year overall survival. Noninferiority was declared if the 3-year overall survival rate after SABR was lower than that after VATS L-MLND by ≤ 12% and the upper bound of the 95% confidence interval (CI) of the hazard ratio (HR) was < 1.965. The final follow-up date was in September 2020.
Overall Survival
Median follow-up was 5.1 years (interquartile range = 3.9–5.8 years). Noninferiority of SABR vs VATS L-MLND was shown. Overall survival in the SABR cohort was 91% (95% CI = 85%–98%) at 3 years and 87% (95% CI = 79%–95%) at 5 years. Overall survival in the VATS L-MLND cohort was 91% (95% CI = 85%–98%) at 3 years and 84% (95% CI = 76%–93%) at 5 years. On multivariate analysis, no significant difference in overall survival was observed between the SABR and VATS L-MLND cohorts (HR = 0.86, 95% CI = 0.45–1.65, P = .65).
KEY POINTS
- SABR was found to be noninferior to video-assisted thoracoscopic surgical lobectomy with mediastinal lymph node dissection.
- Overall survival at 3 and 5 years was 91% and 87% with SABR.
In the SABR cohort, median progression-free survival was not reached (95% CI = not reached–not reached), with 3- and 5-year rates of 80% (95% CI = 72%–89%) and 77% (95% CI = 68%–87%). Median cancer-specific survival was not reached (95% CI = not reached–not reached), with 3- and 5-year rates of 95% (95% CI = 90%–100%) and 92% (95% CI = 86%–98%).
Adverse Events
In the SABR cohort, grade ≥ 2 adverse events consisted of one case each of grade 2 pneumonitis, grade 2 lung fibrosis, and grade 3 dyspnea. No grade 4 or 5 adverse events and no serious adverse events were reported. No treatment modifications or interruptions were required.
The investigators concluded, “Long-term survival after SABR is noninferior to VATS L-MLND for operable stage IA NSCLC. SABR remains promising for such cases, but multidisciplinary management is strongly recommended.”
Joe Y. Chang, MD, of the Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, is the corresponding author for The Lancet Oncology article.
Disclosure: The study was funded by Varian Medical Systems and the National Cancer Institute. For full disclosures of the study authors, visit thelancet.com.