By Gene Emery

(Reuters Health) – A large study of smokers and ex-smokers in the Netherlands and Belgium is confirming that widespread screening using low-dose CT scans can dramatically lower the lung cancer death rate.

After 10 years, the mortality rate for men who received regular screening was reduced by 24% compared to men who got no screening. Although women were under-represented in the study, the research team found that screening lowered their risk of dying from lung cancer by 33%. A total of 15,792 people volunteered for the study.

The decline “is significant and clear-cut for males. It seems even more effective in females,” lead study author Dr. Harry de Koning of Erasmus Medical Center in Rotterdam told Reuters Health in a telephone interview.

The researchers estimated that four rounds of screening over about five years prevented 60 deaths from lung cancer among the 6,583 screened. The rate of false alarms was 1.2%.

The findings buttress results from the United States, released in 2011 from the National Lung Screening Trial, showing a 20% reduction in mortality with CT screening.

Although U.S. guidelines began endorsing routine lung cancer screening after the release of the 2011 findings, European countries has been slower to adopt the practice because studies done there have been small or inconclusive.

Will the new findings change practice in Europe?

“They really should,” said de Koning, a professor of public health at Erasmus. “This is the second large trial showing it works and it shows an even bigger effect than the first trial.”

“These doubts should be laid to rest” by a new study, known as NELSON, Stephen Duffy of Queen Mary University of London and John Field of the University of Liverpool in the UK write in an editorial accompanying the study in the New England Journal of Medicine.

“Our job is no longer to assess whether low-dose CT screening for lung cancer works: it does,” they write. “Our job is to identify the target population in which it will be acceptable and cost-effective.”

Lung cancer kills more people worldwide than any other type of cancer. It’s responsible for 18.4% of all cancer deaths, in part because 70% of the people diagnosed with the disease are already at an advanced stage when it’s discovered. Only 15% survive for five years.

The new findings are “going to be extremely impactful,” said Dr. Andrea McKee, who directs the CT lung cancer screening program at the Lahey Hospital and Medical Center in Burlington, Massachusetts, and was not involved in the study.

The NELSON trial, which looked at different screening intervals, also found that the low-dose CT scans should be done in smokers and former smokers once a year, de Koning said.

“Two and a half years between scans was really too long” and the tumors that were detected were caught too late, he said.

“When you do annual screening, 88% of patients have stage 1 or 2 disease,” McKee told Reuters Health in a telephone interview. “It’s incredible the number of lives we’re going to save” when screening becomes as accepted as mammography, which uses a comparable dose of radiation to detect breast cancer.

SOURCE: The New England Journal of Medicine, online January 29, 2020.