But chemotherapy often can’t kill off a solid tumor completely. Focused radiation can step in and destroy those clumps of cancer cells, acting in conjunction with chemo, explained Movsas, who was not involved with the studies.
The first presentation involved long-term results from a major chemoradiation therapy trial that started in 2006. The study involved more than 500 patients treated at 185 hospitals in the United States and Canada. They all had inoperable stage 3 lung cancer that had not spread to other parts of the body.
The researchers reported that the overall five-year survival rate from this combination therapy was 32 percent, more than twice as high as previous estimates.
“That’s the new benchmark for stage 3 lung cancer. About one-third of patients are alive at five years,” said principal investigator Dr. Jeffrey Bradley. He’s director of the S.L. King Center for Proton Therapy at the Washington University School of Medicine in St. Louis.
“A third of patients are alive at five years — that’s as close to cure as you can get,” Movsas said. “For me, that’s a real step forward and a very, very promising result.”
The second study looked into whether radiation therapy could be added to chemo to control cancer that had spread into other parts of the body such as the brain, liver, bone and pancreas.
For this clinical trial, researchers used radiation therapy on 14 patients whose lung cancer had spread to six or fewer sites elsewhere in the body. Beam radiation targeted both the main tumor and the new cancer sites.