“There is evidence that a fairly simple, five-minute, low-dose, low-radiation scan can really save many lives,” said Dr. Bernard J. Park, pulmonary surgeon and clinical director of the lungs. Screening service at the Memorial Sloan Kettering Cancer Center in New York. Around 75 to 85 percent of the cancers found in this screening are in stage 1 and it is estimated that only surgery or radiation can be cured.

Dr. Park said that many people who signed up for screening had quit smoking or were trying to quit, but that some viewed clear scans as a sign that they could continue smoking.

Dr. Smith said the American Cancer Society should revise its own guidelines for lung cancer screening and that its advice would likely be similar to that of the task force.

In 2013, the American Academy of Family Physicians declined to recommend for or against CT screening for lung cancer because of insufficient evidence. But the President, Dr. Ada Stewart, in a statement emailed Monday, said the academy would review the task force’s new evidence and decide whether to update its own recommendation to its members.

There were 2.09 million new cases of lung cancer worldwide in 2018, and the disease is also the leading cause of cancer deaths according to the World Health Organization. That year 1.76 million people died.

According to the National Cancer Institute, there were 228,820 new cases of lung cancer in the U.S. in 2020, killing 135,720 people. About 90 percent of cases occur in people who smoke, and the current risk for smokers of developing the disease is about 20 times that of non-smokers.

Only about 20.5 percent of patients survive five years after diagnosis. Most cases are diagnosed late after the cancer has spread. But if it can be found and treated early, a cure is possible, doctors say.