Sterotactic body radiation therapy (SBRT) was found to improve overall survival in two different populations of patients with non-small cell lung cancer (NSCLC), according to two studies presented at the American Society for Radiation Oncology annual meeting.

Veterans With Stage I NSCLC

The first study looked at using SBRT in U.S. veterans with stage I NSCLC. Researchers analyzed data from more than 14,000 patients in the Veterans Affairs Central Cancer Registry between 2001 and 2010. A total of 3,012 patients received radiotherapy; of those, 468 had SBRT and 1,203 had conventional radiotherapy.

Four-year overall survival was 37% with SBRT and 18.8% with conventional radiotherapy. Four-year lung cancer survival was also improved, at 53.2% for SBRT and 28.3% for conventional radiation.

After adjusting for confounding factors, the researchers found that SBRT reduced risk of death by 28% over conventional radiotherapy. They noted that their findings add to the growing body of evidence that SBRT should be standard treatment for stage I NSCLC.

Older Adults With NSCLC

Survival in older adults treated with SBRT for early-stage NSCLC also improved significantly, rising from 40% to 60% during the past decade. Researchers evaluated data from 62,213 older adult patients with stage I NSCLC in the National Cancer Institute’s Surveillance, Epidemiology, and End Results database, analyzing changes in overall and cancer-specific survival rates from 2004–2012. This study looked at SBRT and surgical treatment, both of which showed improvements in survival.

Overall survival rates at 23 months for patients treated with SBRT rose from 39% in 2004 to 58% in 2012. Patients treated with surgery alone also saw a smaller increase in survival, rising from 79% in 2004 to 84% in 2012. Cancer-specific survival rose from 48% to 72% for SBRT and from 91% to 97% for surgery.

The researchers noted that although survival rates continue to be lower for SBRT compared to surgery, this finding may be the result of a selection bias where patients who are healthier at diagnosis are treated with surgery.