US advises CT scans for younger and lighter smokers in drive against lung cancer

New guidelines from medical experts will nearly double the number of people in the United States who are advised to have yearly CT scans to screen for lung cancer, and will include many more African Americans and women than in the past, writes Denise Grady for The New York Times. But some who need scans most may not be able to afford them.

The disease is the leading cause of US cancer deaths, and the goal of the expanded screening is to find it early enough to cure it in more people at high risk because of smoking. In those individuals, annual CT scans can reduce the risk of death from the cancer by 20% to 25%, large studies have found.

The new recommendations, by the US Preventive Services Task Force, include people ages 50 to 80 who have smoked at least a pack a day for 20 years or more, and who still smoke or have quit within the past 15 years.

The advice, published on Tuesday in the medical journal JAMA, differs in two major ways from the task force’s previous guidelines, issued in 2013. It lowers the age when screening should start, to 50 from 55, and it reduces the smoking history to 20 years, from 30.

Those changes will add more women and African Americans to the pool eligible for screening, because they tend to smoke less heavily than the white male study participants on whom earlier guidelines were based.

Women and Black Americans also tend to develop lung cancer earlier and from less tobacco exposure than do white men, experts said. Why the risk appears to differ by race and gender is not known.

“Some studies have alluded to some hormonal influences in women,” Dr Mara Antonoff, a lung surgeon at the MD Anderson Cancer Center in Houston, said in an interview with The New York Times. “In terms of racial differences, we don’t have an answer.

“We have population-based data to show they have a tendency to develop lung cancer younger and with less exposure to tobacco, but we don’t have a mechanism.”

Under the new criteria, 14.5 million people in the United States will qualify for the screening, an increase of 6.4 million.

The task force includes 16 physicians, scientists and public health experts who periodically evaluate screening tests and preventive treatments. Members are appointed by the director of the federal Agency for Healthcare Research and Quality, but the group is independent and its recommendations often help shape US medical practice.

The use of chest X-rays to detect lung cancer was largely abandoned decades ago because they could not find the disease early enough to be useful.

The New York Times article continues: The CT scans, called low-dose CT – because they involve a relatively small amount of radiation – cost about $300. Patients are advised to stop the screening once they have not smoked for 15 years, or if they develop health problems that would substantially shorten their life expectancy or make them unable to have lung surgery if needed.

Patients have not flocked to clinics for this screening. Researchers estimate that only 6% to 18% of those who qualify and could be helped by the screening have taken advantage of it. Some cannot afford it.

“Part of the low uptake is simply lack of access to care,” said Dr Robert Smith, a screening expert at the American Cancer Society. “Smoking in general is increasingly concentrated in lower-income populations.”

The Affordable Care Act does require that insurers cover any screening broadly recommended by the task force, with no out-of-pocket costs.

But researchers have found that half the population eligible for lung cancer screening had either no insurance, or Medicaid, Smith said. Not all Medicaid plans have covered the screening, according to an editorial in JAMA.

“There could be a 15-year period when you might quality for screening and not have any insurance,” Smith told The New York Times. He and other researchers also said that patients may be missing out on lung-cancer screening because they just don’t know about it.

The changes in the criteria for smoking history and screening age were based on new data from multiple studies.

Smith said that the American Cancer Society was due to revise its own guidelines for lung-cancer screening, and that its advice would probably be similar to that of the task force. And the American Academy of Family Physicians told The New York Times that it would review the new task force evidence and decide whether to update its recommendation.

Globally, there were 2.09 million new cases of lung cancer in 2018, and the disease is also the leading cause of cancer deaths, killing 1.76 million people that year, according to the World Health Organization.

Link to the full The New York Times article below.


Study details

Screening for Lung Cancer – US Preventive Services Task Force Recommendation Statement

US Preventive Services Task Force members: Alex H Krist, Karina W Davidson, Carol M Mangione, Michael J Barry, Michael Cabana, Aaron B Caughey, Esa M Davis, Katrina E Donahue, Chyke A Doubeni, Martha Kubik, C Seth Landefeld, Li Li, Gbenga Ogedegbe, Douglas K Owens, Lori Pbert, Michael Silverstein, James Stevermer, Chien-Wen Tseng and John B Wong.

Published by JAMA Network on 9 March 2021.



Lung cancer is the second most common cancer and the leading cause of cancer death in the US. In 2020, an estimated 228,820 persons were diagnosed with lung cancer, and 135,720 persons died of the disease.

The most important risk factor for lung cancer is smoking. Increasing age is also a risk factor for lung cancer. Lung cancer has a generally poor prognosis, with an overall 5-year survival rate of 20.5%. However, early-stage lung cancer has a better prognosis and is more amenable to treatment.


To update its 2013 recommendation, the US Preventive Services Task Force (USPSTF) commissioned a systematic review on the accuracy of screening for lung cancer with low-dose computed tomography (LDCT) and on the benefits and harms of screening for lung cancer and commissioned a collaborative modelling study to provide information about the optimum age at which to begin and end screening, the optimal screening interval, and the relative benefits and harms of different screening strategies compared with modified versions of multivariate risk prediction models.


This recommendation statement applies to adults aged 50 to 80 years who have a 20 pack-year smoking history and currently smoke or have quit within the past 15 years.

Evidence assessment

The USPSTF concludes with moderate certainty that annual screening for lung cancer with LDCT has a moderate net benefit in persons at high risk of lung cancer based on age, total cumulative exposure to tobacco smoke, and years since quitting smoking.


The USPSTF recommends annual screening for lung cancer with LDCT in adults aged 50 to 80 years who have a 20 pack-year smoking history and currently smoke or have quit within the past 15 years.

Screening should be discontinued once a person has not smoked for 15 years or develops a health problem that substantially limits life expectancy or the ability or willingness to have curative lung surgery. (B recommendation)

This recommendation replaces the 2013 USPSTF statement that recommended annual screening for lung cancer with LDCT in adults aged 55 to 80 years who have a 30 pack-year smoking history and currently smoke or have quit within the past 15 years.


The New York Times article – Yearly Lung Cancer Scans Are Advised for People 50 and Over With Shorter Smoking Histories (Limited access) 

JAMA Network article – Screening for Lung Cancer: US Preventive Services Task Force Recommendation Statement (Open access) 



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