Lung cancer screening and the indication-creep blues

A new secondary analysis of the data collected for the National Lung Screening Trial (NLST) was published this week, an apparent response to MEDCAC’s no-confidence vote in low-dose CT lung cancer screening.

In their introduction, a team of researchers from the National Institutes of Health, Washington University, Marshfield Clinic and Duke University note the screening examination’s B grade from the U.S. Preventive Services Task Force and the subsequent no confidence vote from MEDCAC.

The authors point out that many of the concerns expressed by MEDCAC were “directly related to age and the uncertainty about the effectiveness and potential for harms” in the Medicare-eligible population. They went on to illustrate that a screening program that replicated the selection process and protocols of the NLST could potentially deliver twice the benefit in the Medicare population as among younger smokers aged 55 to 64 aged.

In their discussion of the results, the researchers point out that 70% of all U.S. lung cancer cases are diagnosed at age 65 or older, a fact borne out by the results of this latest analysis—twice the number of screen-detected cancers were found in the NLST’s 65+ cohort compared to the 55 to 64 cohort.

As someone interested in the translation of research into practice, lead author Paul Pinsky, PhD, MPH, is understandably careful about drawing conclusions about how research outcomes will play in the real world.  He is acting chief, early detection research group, division of cancer prevention, National Cancer Institute. Nonetheless, this latest use of the NLST data begs the question: Why not LDCT lung cancer screening for Medicare patients?

This is a question that the authors answer in their conclusion: It is difficult to predict how LDCT will disseminate in the Medicare-eligible population.

Can the parameters and protocols of the NLST be replicated by our healthcare delivery system?  Will patients come back five years in a row when they get a negative scan? Can providers prevent indication creep?

As this latest take on the NLST results makes clear, it is in the very best interest of the Medicare-eligible population to find affirmative answers to those questions.

Cheryl Proval