Radiation Therapy Increases Survival in Certain Lung Cancer Patients

Treating certain lung cancer patients with surgery followed by radiation therapy can improve their chances of long-term survival, according to a study of more than 7,000 patients. The results, which suggest the need to reconsider radiation therapy's role in treatment, are reported today in the Journal of Clinical Oncology.

"Post-operative radiation therapy has failed to demonstrate a survival benefit in the past, likely because previous studies used older equipment," said Brian Lally, M.D., a radiation oncologist at Wake Forest University Baptist Medical Center and lead author. "Our study, which examines the results using modern equipment, shows survival benefit in select patients."

The study analyzed data from the Surveillance, Epidemiology and End Results Database (SEER), a national program that collects information on cancer cases from registries that represent 26 percent of the U.S. population. Lally began the research at Yale University School of Medicine before he joined Wake Forest Baptist.

The analysis found that in patients whose disease had spread to the regional lymph nodes between the lungs, overall survival at five years was 27 percent in patients receiving surgery plus radiation therapy, compared to 20 percent in patients who were treated with surgery alone.

"Lung cancer is the leading cancer killer in this country and even with the best therapy, survival is poor; so an increase of this level can be considered significant," said Lally. "I speculate that the improvement in the technology available to deliver radiation therapy is responsible for this increase."

In the past, the combination of surgery/radiation therapy was the standard of care for lung cancer. However, this practice shifted dramatically after an analysis of nine studies found that radiation therapy had a detrimental effect on survival. Today, most lung cancer patients are treated with surgery and chemotherapy and less than one-third receive radiation therapy.

Many of the patients in the older studies were treated with cobalt-60 radiation therapy and the side effects could include damage to heart and lung tissue. Today, most hospitals offer therapy with linear accelerators - a more precise treatment.

The goal of Lally's research was to determine if the advances in radiation therapy technology would result in improved survival. Researchers analyzed results of 7,465 patients who had surgery for lung cancer. About half (47 percent) received radiation therapy after the surgery and 53 percent didn't.

In all patients, Lally and colleagues found that radiation treatment did not impact survival. However, when patients were compared based on lymph node involvement, there were clear differences. In patients where cancer had spread to high-risk regional lymph nodes, survival was improved with radiation therapy.

"For the patients who received surgery and radiation therapy, their survival was better than patients who received surgery alone," said Lally.