The case for targeted screening programs for lung cancer has been bolstered by results from the European NELSON study, a leading UK clinician argues.
Professor David Baldwin, consultant respiratory physician in Nottingham and a member of NHS England’s advisory group on lung cancer, said the long-awaited results from the NELSON study meant there would likely be full implementation of a UK-wide targeted screening program based on low-dose CT in high risk patient.
The results of the 10-year study published in February showed a substantial reduction in lung cancer mortality in high-risk former and current smokers who had undergone lung cancer screening at year 1, 3 and 5.
Among 13,195 men in the study, 156 men with a lung-cancer diagnosis in the screening group and 206 in the control group had died from lung cancer – a cumulative rate ratio for death from lung cancer of 0.76, the researchers reported in the New England Journal of Medicine.
There appeared to be a greater 33% reduction in lung cancer deaths for women but the numbers were small as only 2494 were screened.
However, as the trial reported no difference in overall mortality rates, the results have caused debate over whether the impact of screening would be great enough to justify potential overdiagnosis and other adverse implications for patients.
In his evidence-based medicine podcast, Plenary Session, US oncologist Dr Vinay Prasad was highly critical of the paper. He said: “You’re subjecting people who are heavy smokers to a battery of invasive tests and being put on the medicalisation pipeline and you don’t know for sure you are improving longevity or quality of life.”
But Professor Baldwin said the all-cause mortality results were not a concern. “The study was far too small to detect an all-cause mortality benefit,” he told the limbic.
He added that the larger US National Lung Screening Trial did find a difference in all-cause mortality.
“Using the disease-specific mortality benefit of 25% and modelling on ONS data, the all-cause mortality benefit approaches that of treatment of cardiovascular disease.”
His comments echo those of an accompanying NEJM editorial that said the 24% reduction in lung cancer mortality seen in NELSON should put to rest any doubts over lung cancer screening.
But questions remained around the apparently increased benefits in women as well as cost effectiveness depending on screening interval and population selection, said the authors Professor Stephen Duffy, from the Centre for Cancer Prevention at Queen Mary University of London and Professor John Field, chief investigator for the UK Lung Cancer Screening Trial.
“Our job is no longer to assess whether low-dose CT screening for lung cancer works: it does. Our job is to identify the target population in which it will be acceptable and cost-effective,” they concluded.