Fewer Americans have been dying of lung cancer in recent years — partly because of advances in treatment, a new government study finds.
The researchers found that after a gradual decline, lung cancer deaths in the United States started to drop more quickly in 2013. That coincided with the introduction of new "targeted" drugs that can more precisely go after certain lung tumors.
Experts called the findings a promising development against a disease that has traditionally had a dismal prognosis.
"We're still far from a cure, but we're making tremendous progress in treating the disease," said Dr. Jacob Sands, a volunteer medical spokesperson for the American Lung Association.
Sands, who was not involved in the study, said the findings are a testament to basic research that has yielded breakthroughs in the understanding of lung cancer.
Researchers have uncovered a number of genetic alterations in lung tumors that, in some people, serve as "drivers" of the disease.
That, in turn, led to the development of so-called targeted drugs that zero in on those aberrant genes — more effectively attacking the cancer, while sparing healthy cells.
Only certain patients have lung tumors with those gene mutations, meaning targeted drugs cannot help everyone.
But, Sands said, recent years have also seen advances in lung cancer immunotherapy — medications that help the immune system find and destroy cancer cells.
"Being diagnosed with lung cancer now is much different than it was 20 years ago," said Sands, who is also an oncologist at the Dana-Farber Cancer Institute in Boston.
The findings were published in the Aug. 13 issue of the New England Journal of Medicine. They're based on government cancer surveillance data for 2001 through 2016.
It was already known that deaths from lung cancer have been decreasing in the United States, in part because of a decline in smoking. But the new findings reveal a recent acceleration — one that cannot be explained solely by fewer lung cancer cases.
Specifically, the decline sped up after the introduction of drugs that target alterations in the EGFR and ALKgenes, said Nadia Howlader, a researcher at the U.S. National Cancer Institute who led the study.
The pattern was seen for non-small-cell lung cancer, which makes up the majority of all lung cancers.
Among U.S. women, death rates from that form of lung cancer dipped by about 2% a year between 2006 and 2014. That decline accelerated to 6% a year from 2014 through 2016. Deaths among men showed a similar pattern — with the decrease speeding up after 2013, to just over 6% a year.
At the same time, lung cancer patients were surviving longer, the study found. Two-year survival odds among both men and women, and patients of all races, were higher in 2014 than 2001.
New drugs are not the only recent change in lung cancer care. In 2014, yearly lung cancer screening became available for certain smokers and former smokers.
However, Howlader said, uptake was slow, so it's unlikely that screening contributed much to the decline in deaths through 2016.
But if screening rates keep improving, Sands said, that will undoubtedly prevent more deaths.
Screening allows more tumors to be detected at an early stage. And an American Cancer Society study estimated that lung cancer screening could prevent 12,000 deaths a year in the United States.
"Current and former smokers should find out whether they qualify for screening," Sands said.
Right now, annual screening with a low-dose CT scan is recommended for a defined group: People ages 55 to 80 who have smoked at least 30 "pack-years" over a lifetime, and either still smoke or have quit within the past 15 years. (A pack year is a pack a day for a year).
A change was recently proposed, however, one that would double the number of Americans who qualify for screening, Sands said. It would lower the starting age to 50, and include people who smoked somewhat less heavily.
After lung cancer is diagnosed, it's critical to determine what type it is, Howlader said. That includes testing the tumor for all "targetable" gene mutations.
In the past several years, Sands said, additional targeted drugs have become available — aimed at not only EGFR and ALK, but certain other genetic alterations found in lung tumors.
"People should ask their oncologist if their cancer is being tested for mutations that have approved therapies," Sands said.
According to Howlader, ongoing research will track whether the most recent treatment advances are further driving down lung cancer deaths.