ASTRO 2017: New Benchmark Set for Survival After Lung Cancer
Five-year follow-up results of phase 3 clinical trial announced this week show significant survival improvement for people with an advanced form of lung cancer.
SAN DIEGO -- The results of a long-term, five-year follow-up from a clinical trial begun a decade ago for people undergoing chemoradiation for treatment of an inoperable form of lung cancer has set a new benchmark for survival according to data presented this week at the American Society for Radiation Oncology meeting in San Diego.
The phase 3 randomized RTOG 0617 trial began in 2006 and accrued 544 people at 185 different medical centers across the United States and Canada who all had just been diagnosed with locally advanced, stage III non-small cell lung cancer.
All the people enrolled in the trial took standard doses of the drugs paclitaxel and carboplatin, and the trial was designed to compare the efficacy of combining that chemotherapy with either a standard dose of radiation (60 gray) or a higher dose (74 gray), both with and without the immunotherapy drug cetuximab (sold under the brand name Erbitux).
According to experts at a press conference held this week, the initial results of the trial were surprising when first reported in 2015 because they showed that people who received the lower dose of radiation had longer survival than those who received the higher dose.
"It sort of shook up the radiation oncology community," said Jeffrey Bradley, speaking at the press conference. Bradley is a professor of radiation oncology at Washington University in St. Louis and was the principle investigator in the trial.
The results, he said, challenged the premise that a higher dose is usually better.
"It wasn't in this case," Bradley said. "60 gray is superior to 74 gray in terms of overall survival and progression-free survival."
Based on those initial trial results two years ago, 60 gray has become the standard of care in the field for treating this type of cancer, Bradley said, and the five-year follow-up data presented this week supported that finding. The trial also showed no survival benefit for taking the drug Cetuximab, which is approved by the U.S. Food and Drug Administration to treat colon cancer and certain types of head and neck cancers.
The data from the clinical trial presented this week showed an 18.3 percent five-year progression-free survival in the standard-dose arm of the trial and only a 13 percent progression-free survival in the high-dose arm. Overall five-year survival was 32 percent (standard dose) versus 23 percent (high dose).
"That sets a new benchmark for stage III lung cancer," Bradley said. "About one-third of patients are alive at five years."
Brian Czito, a radiation oncologist at Duke University who was not involved in the research, agreed. The 32 percent of the trial participants surviving five years after treatment for locally advanced non-small cell lung cancer is significantly improved over what we have seen in years past, he said to reporters after moderating the press conference this week at which the results were first announced.
"This study confirms that 60 gray should be the standard dose of radiation in these patients," Czito said.