PULMONARY NODULE
Evaluation is guided by nodule size & assessment
of probability of malignancy. In addition is based on the yield of available
diagnostic testing, patient comorbidities, & patient preferences. Focal
pulmonary lesions that are > 3 cm in diameter are called lung masses &
should be considered malignant until proven otherwise.
Pulmonary nodules are categorized as small solid
(<8 mm), larger solid (≥8 mm), and subsolid.
Subsolid nodules are divided into ground-glass nodules
(no solid component) and part-solid (both ground-glass and solid components).
The probability of malignancy is less than 1% for all
nodules smaller than 6 mm and 1% to 2% for nodules 6 mm to 8 mm.
Nodules that are 6 mm to 8 mm can be followed with a
repeat chest CT in 6 to 12 months, depending on the presence of patient risk
factors and imaging characteristics associated with lung malignancy, clinical
judgment about the probability of malignancy, and patient preferences.
The treatment of an individual with a solid pulmonary
nodule 8 mm or larger is based on the estimated probability of malignancy; the
presence of patient comorbidities, such as chronic obstructive pulmonary
disease and coronary artery disease; and patient preferences. Management
options include surveillance imaging, defined as monitoring for nodule growth
with chest CT imaging, positron emission tomography-CT imaging, nonsurgical
biopsy with bronchoscopy or transthoracic needle biopsy, and surgical
resection.
Part-solid pulmonary nodules are managed according to
the size of the solid component.
Larger solid components are associated with a higher risk
of malignancy.
Ground-glass pulmonary nodules have a probability of
malignancy of 10% to 50% when they persist beyond 3 months and are larger than
10 mm in diameter.
A malignant nodule that is entirely ground glass in
appearance is typically slow growing.
Current bronchoscopy and transthoracic needle biopsy
methods yield a sensitivity of 70% to 90% for a diagnosis of lung cancer.
