■ A U.S. health panel expanded guidelines to screen more smokers for lung cancer.

More Americans now qualify for yearly scans to detect lung cancer, according to guidelines released Tuesday that may help more Black smokers and women get screened.

Lung cancer is the nation’s top cancer killer, causing more than 135,000 deaths each year. Smoking is the chief cause and quitting the best protection.

Usually, lung cancer is diagnosed too late for a good chance at survival. But some Americans who are at especially high risk get an annual low-dose CT scan, a type of X-ray, to improve those odds.

Who’s eligible? The U.S. Preventive Services Task Force said anyone ages 50 to 80 who has smoked at least 20 “pack-years” and either still smokes or quit within the last 15 years. A “packyear” means smoking a pack of cigarettes a day for a year or an equivalent amount. So, someone could qualify by going through a pack a day for 20 years or two packs a day for 10 years.

Since 2013, the scans have been recommended for heavier smokers — 30 pack-years — and those a little older, starting at 55. The task force updated the guidelines, published Tuesday in the Journal of the American Medical Association, after newer research showed lighter, younger smokers benefit, too. About 15 million people are estimated to meet the new criteria, nearly double the previous number.

The task force recommendation means insurers must offer the screening without a copay to people who meet the criteria.

The changes “mean more Black people and women are now eligible for lung cancer screening,” Dr. John B. Wong, a task force member, said in a statement.

The panel said African Americans and women tend to be less heavy smokers and may not have met the earlier screening threshold despite being at risk for lung cancer.