At 10 years, stereotactic ablative radiotherapy (SABR) offers survival outcomes comparable to surgery for patients with small, early-stage non-small cell lung cancer, according to research presented at the American Society for Radiation Oncology (ASTRO) meeting.
The finding is from a prospective phase II trial comparing the approach to standard-of-care video-assisted thoracoscopic lobectomy with mediastinal lymph node removal (VATS L-MLND), noted principal investigator Joe Chang, of the University of Texas MD Anderson Cancer Center.
“Through 10 years of follow-up, there was no significant difference between SABR and VATS L-MLND in overall survival, cancer-specific survival, and recurrence-free survival,” Chang said, in a September 30 ASTRO media briefing.
Non-small cell lung cancer (NSCLC) accounts for more than 85% of all lung cancers. An estimated 226,650 U.S. adults are expected to be newly diagnosed with the disease in 2025, Chang noted. Many of these patients have comorbidities that make surgery intolerable and even for operable cases, surgical complications remain significant, he added.
Conversely, SABR is noninvasive and involves delivering high doses of radiation with high accuracy over typically five or fewer treatment sessions. In 2021, in The Lancet Oncology, Chang and colleagues reported favorable outcomes comparing SABR with surgery after five years.
Between 2015 and 2017, 80 patients with early-stage NSCLC (<3 cm, with no lymph node involvement or distant metastasis) were recruited and underwent 15 minutes of SABR per day for three to four days as an outpatient procedure. These patients were matched with 80 patients who underwent surgery. The primary endpoint for the comparison was overall survival.
According to the analysis, overall survival was virtually identical between groups: 69% of patients treated with SABR and 66% treated with surgery were alive 10 years after treatment. The rates of lung cancer-specific survival (92% versus 89%) and recurrence-free survival (57% versus 65%) were also similar for both patient cohorts.
In addition, the rate of moderate to severe short-term complications was higher with surgery (50%) compared to SABR (1%), Chang noted.
“SABR remains an option for operable NSCLC with improved short-term complication rates as compared with VATS L-MLND. A multidisciplinary discussion is strongly recommended,” Chang said.
Ultimately, SABR isn’t for every patient, Chang noted. For example, for patients whose tumors are more complex, larger, or located in certain areas, surgery remains the best treatment option.
“This study confirms that SBRT is an effective alternative that should be considered,” Chang said.
The researchers are now exploring strategies to further reduce recurrence rates, including pairing local therapies with immunotherapy and using artificial intelligence tools to predict hidden lymph node involvement before it appears on PET/CT scans, Chang said.
