National Lung Screening Trial Findings by Age: Medicare-Eligible Versus Under-65 Population
Mené aux Etats-Unis auprès de deux cohortes incluant respectivement 19 612 participants âgés de 55 à 64 ans et 7 110 participants âgés de 65 à 74 ans, cet essai multicentrique évalue, en fonction de deux catégories d'âge et du point de vue des taux de faux positifs, de complications liées aux protocoles et du taux de survie à 5 ans, l'intérêt d'un programme de dépistage du cancer du poumon par tomographie numérique à faible dose de rayonnements ionisants
Background : The NLST (National Lung Screening Trial) showed reduced lung cancer mortality in high-risk participants (smoking history of ≥30 pack-years) aged 55 to 74 years who were randomly assigned to screening with low-dose computed tomography (LDCT) versus those assigned to chest radiography. An advisory panel recently expressed reservations about Medicare coverage of LDCT screening because of concerns about its performance in the Medicare-aged population, which accounted for only 25% of the NLST participants.
Objective : To examine the results of the NLST LDCT group by age (Medicare-eligible vs. <65 years).
Design : Secondary analysis of a group from a randomized trial (NCT00047385).
Setting : 33 U.S. screening centers.
Patients : 19 612 participants aged 55 to 64 years (under-65 cohort) and 7110 participants aged 65 to 74 years (65+ cohort) at randomization.
Intervention : of LDCT screening.
Measurements : Demographics, smoking and medical history, screening examination adherence and results, diagnostic follow-up procedures and complications, lung cancer diagnoses, treatment, survival, and mortality.
Results : The aggregate false-positive rate was higher in the 65+ cohort than in the under-65 cohort (27.7% vs. 22.0%; P < 0.001). Invasive diagnostic procedures after false-positive screening results were modestly more frequent in the older cohort (3.3% vs. 2.7%; P = 0.039). Complications from invasive procedures were low in both groups (9.8% in the under-65 cohort vs. 8.5% in the 65+ cohort). Prevalence and positive predictive value (PPV) were higher in the 65+ cohort (PPV, 4.9% vs. 3.0%). Resection rates for screen-detected cancer were similar (75.6% in the under-65 cohort vs. 73.2% in the 65+ cohort). Five-year all-cause survival was lower in the 65+ cohort (55.1% vs. 64.1%; P = 0.018).
Limitation : The oldest screened patient was aged 76 years.
Conclusion : NLST participants aged 65 years or older had a higher rate of false-positive screening results than those younger than 65 years but a higher cancer prevalence and PPV. Screen-detected cancer was treated similarly in the groups.
Primary Funding Sourceb : National Institutes of Health.
Annals of Internal Medicine , résumé, 2013