Evaluation of solitary pulmonary nodule

A solitary pulmonary nodule is defined as a relatively round lesion that is <3 cm in diameter and completely surrounded by lung parenchyma. It is distinct from lung lesions >3 cm in diameter, which are considered lung masses. Traditionally, the definition of solitary pulmonary nodule has also excluded a ground-glass infiltrate seen on computed tomography (CT) scan, as this finding is commonly associated with bronchoalveolar cell carcinoma and does not fulfill the physical characteristics of a nodule.[1]Aoki T, Nakata H, Watanabe H, et al. Evolution of peripheral lung adenocarcinomas: CT findings correlated with histology and tumor doubling time. AJR Am J Roentgenol. 2000 Mar;174(3):763-8. http://www.ajronline.org/doi/full/10.2214/ajr.174.3.1740763 http://www.ncbi.nlm.nih.gov/pubmed/10701622?tool=bestpractice.com For the purposes of this topic, we will consider ground-glass opacities as solitary pulmonary nodules.

Management goals

The goals in managing a patient with a solitary pulmonary nodule are to distinguish the benign from the malignant nodule and, when malignancy is either confirmed or strongly suspected, to expedite resection.

For solitary pulmonary nodules, established clinical features (e.g., patient age, smoking status) and radiographic findings (e.g., calcification, growth rate, size) help determine a probability of malignancy. If necessary, noninvasive and/or invasive testing is used to more accurately determine the probability of malignancy to a level that enables a decision to be made regarding observation or resection. Therefore, the proper use of these tests mandates knowledge about their performance characteristics. Decision analysis approaches using Bayesian methods may also assist with the calculation of the probability of malignancy, although these methods have not consistently outperformed the clinical assessment and testing approach.[2]Tan BB, Flaherty KR, Kazerooni EA, et al. The solitary pulmonary nodule. Chest. 2003 Jan;123(1 Suppl):89S-96S. http://www.ncbi.nlm.nih.gov/pubmed/12527568?tool=bestpractice.com