Interstitial Lung Disease as an Incidental Finding on Computed Tomography

Screening for lung cancer with computed tomography (CT) yields not only false-positive nodules (i.e., nodules that are ultimately benign), but also other incidental findings, including interstitial lung abnormalities (ILAs). To determine the prevalence of ILAs in smokers, researchers closely reviewed a random sample of CT scans from 884 smokers who participated in the recently published National Lung Screening Trial (NEJM JW Gen Med Jul 14 2011); none were known to have lung fibrosis at enrollment.

Fully 9.7% of participants had findings consistent with ILA: Findings were nonfibrotic in 5.9%, fibrotic in 2.1%, and mixed in 1.7%. Among those with ILA, follow-up scans at 2 years showed that abnormalities improved in 33%, were unchanged in 47%,…