What further diagnostic steps may be implemented in the workup of indeterminate pulmonary nodules?
Comparison with prior imaging studies is the first step, as long-term stability is suggestive of benignity. Thin-section unenhanced computed tomography (CT) is the next most common step for further evaluation of indeterminate pulmonary nodules and is useful for identifying the presence of fat or specific patterns of calcification within a nodule that indicate benignancy. Fluorodeoxyglucose (FDG) positron emission tomography (PET), follow-up chest CT, and tissue sampling are some other options available for the workup of indeterminate pulmonary nodules. The choice is based on multiple factors, including the pretest probability of malignancy, the morphologic features of the nodules, and the patient’s clinical history and current status. Although CT nodule densitometry and MRI may also be useful to characterize lung nodules as benign or malignant, they are uncommonly used for this purpose in clinical practice.
