Decade-Long Data Show SABR Matches Surgery for Early-Stage NSCLC Survival

New evidence presented at the American Society for Radiation Oncology (ASTRO) 2025 Annual Meeting suggests that stereotactic ablative radiotherapy (SABR) provides long-term survival outcomes equivalent to surgery for patients with small, operable non-small cell lung cancer (NSCLC), while offering fewer side effects and a less invasive treatment course.

The findings come from the phase II STARS trial (NCT02357992), the first prospective study to report 10-year outcomes directly comparing SABR with surgical resection. Investigators at MD Anderson Cancer Center found overall survival rates virtually identical between patients treated with SABR and those who underwent lobectomy, providing robust evidence to support SABR as a viable option even for operable candidates.

“Our study confirms, based on a decade of data, that stereotactic radiotherapy is a strong alternative to surgery for most patients with operable stage I NSCLC,” said Joe Y. Chang, MD, PhD, FASTRO, professor of thoracic radiation oncology and senior author of the trial. “This highly targeted, non-invasive treatment achieved the same long-term overall survival as lobectomy, while offering many patients an easier recovery and potentially better quality of life.”

NSCLC accounts for more than 85% of lung cancers, with roughly 226,650 new U.S. cases expected in 2025. Surgery has long been the gold standard for early-stage disease, but many patients face significant postoperative complications, and others are poor surgical candidates due to age or comorbidities. SABR, also known as stereotactic body radiation therapy (SBRT), delivers high-dose radiation in three to five fractions with submillimeter accuracy, minimizing collateral damage to healthy lung tissue.

The STARS trial enrolled 80 patients with tumors under 3 cm, no nodal involvement, and no distant metastases, all of whom were deemed fit for either treatment. Patients received SABR in three to four sessions between 2015 and 2017. For comparison, a matched cohort of 80 patients underwent video-assisted thoracoscopic (VATS) lobectomy with mediastinal lymph node dissection during the same period. Both groups were followed for up to 10 years to assess survival, recurrence, side effects, and quality of life.

At a median follow-up of 8.3 years, overall survival was 69% for SABR and 66% for surgery. Lung cancer–specific survival was similarly high (92% for SABR vs. 89% for surgery), while recurrence-free survival was also comparable (57% vs. 65%). Importantly, SABR patients reported fewer side effects, with no treatment-related hospitalizations or deaths and only three cases of grade 2–3 toxicities.

Dr. Chang noted that long-term quality of life remained favorable among the SABR group, supporting its role as a less disruptive alternative to surgery. However, he emphasized that surgery may still be preferable for patients with larger or more complex tumors, highlighting the need for multidisciplinary collaboration in treatment planning.

Looking ahead, the research team is investigating strategies to further reduce recurrence rates, which still affected about one-third of patients in both arms. Potential approaches include combining SABR with immunotherapy and using artificial intelligence to identify occult lymph node involvement before it becomes clinically evident.

“This study provides the clearest evidence yet that SABR is not just an option for inoperable patients, but a legitimate alternative for many operable ones as well,” Dr. Chang concluded. “Our next challenge is to push survival even higher by pairing SABR with novel systemic strategies.”