Results of a phase III randomized international clinical trial showed that patients with operable stage I non-small cell lung cancer (NSCLC) treated with Stereotactic Ablative Radiotherapy (SABR) reached better overall survival rates when compared to current standard treatment. The study conducted by researchers at The University of Texas MD Anderson Cancer Center was published in The Lancet Oncology.
“For the first time, we can say that the two therapies are at least equally effective, and that SABR appears to be better tolerated and might lead to better survival outcomes for these patients,” said in a recent news release study’s first author and principal investigator Joe Y. Chang, M.D., Ph.D., professor, Radiation Oncology. “Stereotactic radiation treatment is a relatively new approach for operable early stage lung cancer, while surgery has been the standard for a century. This study can give physicians confidence to consider a non-invasive option.”
In the study, the team examined overall survival rates, recurrences and toxicity in a total of 58 patients with NSCLC, with results revealing a 79% survival rate at three years in those patients who underwent surgery compared to a 95% survival rate in patients who were treated with SABR. The results also showed that at three years, the rates of recurrence-free survival for patients who underwent surgery or treatment with SABR were 80% and 86%, respectively.
Concerning overall morbidity, a total of six patients who underwent surgery died, while in the SABR group only one patient died. In patients undergoing SABR, the researchers determined that nine patients exhibited high-grade toxicity.
In the United States, according to the Centers for Disease Control and Prevention, Lung cancer is a leading cause of death in both men and women. According to the National Cancer Institute, about half the patients with lung cancer die within one year after diagnosis, and it is expected that in 2015 about 158,040 Americans will die from the condition.
“The findings of our study provide strong support for a large clinical trial to investigate the potential superiority of SABR for patients with early-stage disease,” said in the news release senior author Jack A. Roth, M.D., Professor and Bud Johnson Clinical Distinguished Chair Department of Thoracic & Cardiovascular Surgery. “While we wait for more data, physicians can consider SABR an effective treatment for these patients, especially for those whom surgery brings high risk.”
SABR has been used as treatment for patients with NSCLC that cannot be treated with surgery, with evidence showing that the clinical outcomes are better than when patients are treated with standard radiation. However this was the first study examining the effects of SABR in patients with operable NSCLC.
Compared to SABR, surgery, particularly lobectomy with dissection of the lymph nodes, was thought to reduce recurrence rates. According to Chang, lung cancer surgery is a complex procedure and while recurrence rates are low, there is a 10-20% chance of the cancer coming back in the regional lymph nodes, the other lobes, and distant organs.
Results from this trial showed no differences in tumor recurrence between patients who received SABR or surgery.
The authors note that the results from should be carefully considered due to the small sample size and because the overall follow-up period was short. In 2015, two other randomized trials will examine these techniques: SABRtooth, which will be conducted in the United Kingdom and will assess SABR versus standard surgery in patients with peripheral stage I NSCLC who are at risk of major complications while under surgery; and VALOR (Veterans Affairs Lung cancer surgery Or stereotactic Radiotherapy trial) which will be conducted in the United States.