How Long Should Small Lung Lesions of Ground-Glass Opacity Be Followed?
Kobayashi Y, Fukui T, Ito S, et al
J Thorac Oncol. 2013;8:309-314
Problematic Findings on Chest CTs
With the introduction of high-resolution chest CTs and now more widespread adoption of screening chest CTs in people at high risk for lung cancer, we see small, ambiguous lung nodules with increasing prevalence. Very common among these is the ground-glass opacity (GGO), a hazy opacity that does not obscure underlying bronchial structures or pulmonary vessels at high-resolution CT, which may represent a benign and transient finding but also often represents a noninvasive, precancerous site of atypical adenomatous hyperplasia or adenocarcinoma in situ that may potentially progress to minimally invasive adenocarcinoma (MIA) or frankly invasive adenocarcinoma of the lung, the last of which is associated with a threatening natural history that may limit survival.
These GGOs may be incidentally discovered, are often very small (under 3 cm, with many even under 1 cm), and are typically asymptomatic, at least until they lead to patient anxiety about the significance and need for serial imaging and potential invasive interventions to clarify the nature of these lesions that often demonstrate no or remarkably slow progression over time. Evidence-based guidelines for solid nodules are more readily available than those specifically for GGOs, but there are 2 critical and still open questions:
1) If these lesions are followed over time and demonstrate stability, how long an interval is required before we can be assured that no intervention is likely to be necessary over time?
2) If a minimal amount of progression is demonstrated over a period of years, what is the appropriate intervention to pursue?