ILAs in CT Lung Cancer Screening Population

Interstitial Lung Abnormalities (ILA) have been previously defined as nondependent changes affecting more than 5% of any lung zone on computed tomography (CT) scans of the lung. Several studies suggest that the prevalence of ILA in participants in non-pulmonary research studies ranges anywhere from 7-9%. Work over the last decade has shown that, despite previous characterization as an asymptomatic research finding, ILA has significant clinical and biological consequences. These include reduced exercise capacity, functional limitations, decreased lung volumes, increased mortality, and in some cases histopathology similar to Idiopathic Pulmonary Fibrosis (IPF). ILA have been detected in lung cancer screening cohorts, where the prevalence of ILA is estimated to be between (10%-20%) to those noted in other research cohorts. Given that a significant proportion of those will have progression, CT lung cancer screening (CTLS) cohorts represent an ideal catchment population for future research and clinical trials. Lahey Hospital and Medical Center was one of the earliest clinical centers to develop a CTLS program in the country. Investigators propose to qualitatively characterize ILA in a large clinical CTLS population.