A lung cancer screening program in the US has significantly increased early stage detection of non-small cell lung cancer and saved around 10,100 lives over four years, a new analysis of real world data estimates.

The US introduced a national lung cancer screening program towards the end of 2013, screening patients aged 55-80 years old deemed at high risk from the disease with low dose computed tomography (CT).

The retrospective observational study, published in the BMJ, used two national cancer registries to identify patients diagnosed with NSCLC between January 2010 and December 2018, with the aim of exploring the benefits of the program in a real world population.

The research team used data from 763,474 patients to determine the annual changes in the percentage of NSCLC diagnosed at stage 1 among those not eligible for screening (aged 45-54) and those that potentially were (55-80 years old), and analysed trends in all cause survival from 2010 to 2018.

The results showed that between 2014-2018 the year-to-year percentages of stage 1 disease diagnosed grew at more than twice the rate seen in the preceding four-year term, with an annual percent change of 4%.

Also, between 2014 to 2018 the rate of increase in median all cause survival in patients aged 55-80 diagnosed with NSCLC nearly tripled (annual percent change 12%) from that seen in 2010 to 2013 (annual percent change 4%), so that by 2018 all cause survival had reached 28.2 months.

“Although the adoption of lung cancer screening has been slow and screening rates have remained low nationally, the findings of this study indicate the beneficial effect that even a small amount of screening can have on lung cancer stage shifts and survival at the population level,” the researchers concluded.

The authors had taken into account several other factors that might have played a role in their findings, such as increases in lung cancer over diagnosis or improved accuracy in clinical staging information, but found none would have resulted in an acceleration of early stage diagnoses.

They did, however, highlight several limitations to the study, such as a lack of information on participants’ smoking history or whether the cancers were detected by incidentally or via low dose CT screening.

Nevertheless, the findings are likely to attract global attention, particularly from countries such as Australia, which is currently considering implementing its own lung cancer screening program.