Anonymous smoker at 4th Street Live on July 24, 2023 in Louisville, KY.
Jahi Chikwendiu | The Washington Post | Getty Images
Only a fraction of people at high risk for lung cancer are screened for the disease, even though it kills more people in the United States than breast, colorectal and prostate cancers combined. New guidelines from the American Cancer Society will make millions more eligible for regular exams that can detect tumors early enough to save lives.
With one important exception, the new guidelines echo existing recommendations from the influential U.S. Preventive Services Task Force. In 2021, the panel said people aged 50 to 80 who had smoked at least 20 “pack years” and were still smoking or had quit in the past 15 years should be tested annually with a CT scan in low doses, a type of X-ray.
Under new guidelines released Wednesday, even heavy smokers who quit 15 or more years ago should have annual tests.
Experts say previous guidelines were based on a flawed premise: The longer a person had quit smoking, the lower the risk of cancer.
A close look at data on people diagnosed with lung cancer found that cancer risk increased with age, even among those who had stopped smoking for 15 years or more, said Dr. William Dahut, scientific director of American Cancer. Society and one of the authors of the guidelines.
Although ex-smokers’ lungs may have improved a little at first, that effect didn’t last, he said.
“People developed a false sense of security,” which may have contributed to the “extremely low” screening rates, Dahut said.
A 2022 report from the American Lung Association indicated that only 5.8% of Americans were screened for lung cancer, and in some states rates were as low as 1%.
“Compare that with mammography, which about two-thirds of women get when they reach a certain age,” he said.
Is lung cancer screening worth it?
Under previous guidelines, 14.3 million people in the United States would be eligible for testing. The new recommendation will affect 5 million more people, Dahut said.
The prognosis for people whose cancer is detected late is poor. The overall five-year survival rate for lung cancers diagnosed between 2012 and 2018 was 23%, the guideline authors note.
More than 80% of people whose lung cancer was detected early through screening were still alive after 20 years, according to a study from the Icahn School of Medicine at Mount Sinai in New York, presented at Radiological Society of North America meeting last year. According to estimates from the Cancer Society, this year there will be 238,340 new cases of lung cancer and 127,070 deaths from this disease.
Lung cancer is so deadly because most people are not diagnosed until it is very late. Many smokers and former smokers don’t realize that a simple low-dose CT scan can detect lung cancers early enough to save their lives. Even among primary care doctors, who would be the ones ordering the tests, “there’s confusion,” Dahut said.
Typically, Medicare and commercial insurance companies pay for the tests recommended by the task force. However, it may be some time before insurance covers the additional people included in the new guidelines, Dahut suggested.
Dr. Chi-Fu Jeffrey Yang, a thoracic surgeon at Massachusetts General Hospital in Boston, has been conducting informal surveys to get a better idea of why people might not get tested.
“We asked people if they had heard of it. No one had,” he said. “But everyone had heard of mammograms for breast cancer, colonoscopies for colorectal cancer, and Pap tests for cervical cancer.”
Current low screening rates are “a national tragedy,” said Dr. David Yankelevitz, director of the lung biopsy service at the Icahn School of Medicine. “This should be by far our best weapon against cancer. The fact that such a small percentage is being detected is quite frightening and a major failure.”
He would like the selection criteria to be even broader, particularly for women, blacks and Native Americans. Research has shown that these groups are more vulnerable to lung cancer, either at lower exposures or at younger ages.
“They are at higher risk at lower ages and lower pack years,” Yankelevitz said.
The change in screening guidelines to include people who have stopped smoking for a long time is “huge,” said Dr. Panagis Galiatsatos, director of the Tobacco Treatment and Cancer Screening Clinic at Johns Hopkins Medicine in Baltimore.
“People in their 40s and 50s who smoked two packs of cigarettes a day as teenagers and young adults often don’t think of themselves as smokers,” he said. “But they need to be scanned.”
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