2. Definition: a single, small (≤30 mm), usually well-circumscribed, radiographic
lesion that is surrounded completely by pulmonary parenchyma.
usually asymptomatic.
typically no associated features on imaging (eg, hilar adenopathy,
atelectasis, or pleural effusion).
focus of the evaluation is the assessment of the probability of
malignancy and the selection of patients for CT scan surveillance,
nonsurgical biopsy, or surgical biopsy.
3.
4. Management options for SPNs include CT surveillance and
nodule sampling or resection.
nodules >30 mm are resected because these lesions have
such a high likelihood of malignancy that the benefit of
resection outweighs the associated risk of surgery.
nodules ≤8 mm (without documented growth) are usually
followed by serial CT scan because these lesions have a low
likelihood of malignancy such that the benefits of resection do
not justify the risk of a technically-difficult resective surgery.
Thus, estimating the probability of malignancy in both of
these settings is unlikely to change the diagnostic strategy.
5. However, the risk of malignancy and diagnostic options are widely variable in
nodules that are 8 to 30 mm.
• The probability of malignancy (low [<5 percent], intermediate [5 to 65
percent] or high [>65 percent])
• Nodule characteristics (eg, size, attenuation, stability)
Calculator: Solitary pulmonary nodule malignancy risk (Brock University cancer
prediction equation)
older age, female sex, family history of lung cancer, emphysema, larger nodule size,
location of the nodule in the upper lobe, part-solid nodule type, lower nodule count,
and spiculation.
