Low-dose CT screening for lung cancer has a value-adding benefit beyond what’s expected of it: The imaging procedure can help with early detection of interstitial lung disease (ILD), a category of progressive-scarring disorders that can be deadly and are frequently present in older smokers.
Mary Salvatore, MD, of the Icahn School of Medicine at Mount Sinai in New York City, and colleagues arrived at this conclusion after reviewing CT scans of 951 patients screened for lung cancer between 2010 and 2014.
Their work is published ahead of print in the American Journal of Roentgenology.
In the study, three thoracic radiologists reviewed the images to identify the ILD findings, which were specifically named as, for example, traction bronchiectasis and ground-glass opacities with traction bronchiectasis.
Salvatore and team found that, of the 951 participants, 63 (6.6 percent) had CT evidence of ILD—a considerably higher rate than the 1.8 percent reported in autopsies, the authors point out.
In addition, some 16 of these 63 had honeycombing, a cystic pattern that turns up in many end-stage ILDs.
The study also found a higher frequency of ILD in men than in women (9.2 percent vs 4.3 percent), which was consistent with data in a comparative registry, while the prevalence of ILD went up with increasing age, increasing pack-years of smoking and severity of emphysema.
Salvatore et al. conclude that identification of CT evidence of early ILD is indeed an added benefit of low-dose screening for lung cancer:
“We believe that recognizing ILD in its earliest, preclinical form in people known to be at increased risk and predicting which patients have disease that will likely progress is yet another collateral benefit of lung cancer screening beyond those already identified and studied.”