Stereotactic radiation therapy (SABR) was found to be noninferior to surgical resection in terms of overall survival for patients with early-stage non–small cell lung cancer (NSCLC), according to 10-year results from the STARS trial presented at the American Society for Radiation Oncology (ASTRO) 67th Annual Meeting (Abstract 268).
“Our study confirms, based on a decade of data, that [SABR] is a strong alternative to surgery for most patients with operable stage I NSCLC,” said senior study author Joe Y. Chang, MD, PhD, FASTRO, Professor of Thoracic Radiation Oncology and Director of Stereotactic Ablative Radiotherapy at The University of Texas MD Anderson Cancer Center. “This highly targeted, noninvasive treatment achieved the same long-term overall survival as lobectomy, while offering many patients an easier recovery and potentially better quality of life.”
Rationale and Study Methods
For patients with early-stage NSCLC who cannot undergo surgery, radiation has typically been the standard alternative. But growing evidence is suggesting that the survival benefits may be comparable to surgery.
“Surgery historically was the only standard option for early-stage NSCLC, but upwards of 50% of patients experience moderate or severe side effects afterward. And as patients age, many cannot tolerate surgery, so there’s a growing demand for noninvasive options that provide durable local control,” Dr. Chang said.
Investigators conducted the phase II noninferiority revised STARS trial to determine if clinical outcomes and quality-of-life impacts from SABR were comparable to that of video-assisted thoracoscopic lobectomy with mediastinal lymph node dissection (VATS L-MLND). All patients in the radiation arm (n = 80) had tumors measuring 3 cm or less, no nodal or metastatic disease, and a performance status between 0 and 2. These patients were compared with a matched cohort of 80 patients from an institutional dataset of prospectively registered patients with NSCLC who underwent VATS L-MLND.
The researchers conducted propensity score matching based on patient and disease characteristics. The study assumed a noninferiority margin of 1.965 for overall survival.
Key Study Findings
The median follow-up was 8.3 years. Median overall survival was 11.4 years in the video-assisted thoracoscopic lobectomy arm and not yet reached in the SABR arm. Between the two arms, no significant difference was reported in terms of overall survival, meaning that the trial met its criteria for noninferiority (hazard ratio [HR] for radiation vs surgery = 0.77; 95% confidence interval [CI] = 0.42–1.44; P = .417). At 7 years, the overall survival rates were 81% in the SABR arm (95% CI = 73%–91%) and 69% (95% CI = 57%–84%) in the surgery arm, and at 10 years the rates were 69% (95% CI = 59%–82%) and 66% (95% CI = 55%–78%), respectively.
“This study offers the clearest picture yet that radiation can also be an appealing option for suitable surgical candidates. It included a larger patient population than previously published randomized studies, and we’ve followed these patients for much longer,” Dr. Chang said.
No differences were found between the treatment arms in terms of lung cancer–specific survival (92% vs 89%; HR = 0.95; 95% CI = 0.31–2.94; P = .928) or recurrence-free survival (57% vs 65%; HR = 1.17; 95% CI = 0.67–2.04; P = .586) at 10 years, either.
“While SABR has delivered excellent long-term results, up to a third of patients treated with local therapies still developed locoregional or distant recurrences from this aggressive cancer. Our goal is to find new ways to push survival even higher," Dr. Chang said.
Rates of moderate to severe short-term complications were understandably much higher in the surgical arm than in the radiation arm.
Twenty-eight percent of 60 patients in the SABR arm who received questionnaires for long-term quality of life and financial toxicity answered the questionnaires. Comparable quality-of-life measurements were noted between the two arms in terms of physical and mental components. Fifty-three percent of the responders denied any financial burdens due to radiation therapy.
Disclosure: For full disclosures of the study authors, visit amportal.astro.org.
