Learning objectives
1. Incidence and etiology of tiny pulmonary nodules.
2. Characteristics that increase risk of malignancy.
3. Issues and uncertainties regarding management of tiny nodules.
4.
Case-based review of tiny pulmonary nodules which prove to represent malignancy.
Background
Tiny pulmonary nodules are less than 6mm in diameter
A pulmonary nodule is a rounded opacity in the lung parenchyma measuring 3 cm or less in diameter (1).
The adjective small has been used to describe nodules that are less than 1 cm in diameter and tiny for pulmonary nodules less than 6 mm in diameter (1).
Tiny pulmonary nodules are best demonstrated on thin section (1 to 2 mm collimation) CT.
Thicker section imaging may cause a small solid nodule to be missed or...
Imaging findings OR procedure details
The most important predictors of malignancy are patient risk factors (smoking status,
prior history of malignancy) and nodule size,
chronicity,
density and growth
When a nodule is identified,
all previous CT scans should be reviewed to determine its chronicity. CT can also provide information about the location,
size,
shape,
margins and attenuation characteristics (12).
Size and growth rate represent the main indicators for determining the nature of a pulmonary nodule (13,
14). Nodule size closely relates to likelihood of malignancy in a nonlinear relationship (2)....
Conclusion
With the widespread use of MDCT the number of detected lung nodules,
particularly tiny nodules,
has significantly increased.
In fact,
about half of heavy smokers or former heavy smokers have non-calcified pulmonary nodules (4).
The majority of these nodules are benign with a risk of lung cancer of less than 1% (2,
4,
10,
13).
However,
occasionally a tiny nodule can prove to represent malignancy.
The management strategy of these nodules is evolving based on knowledge from screening studies and a better understanding of the...
References
1. Austin JH,Müller NL,Friedman PJet al.Glossary of terms for CT of the lungs: recommendations of the Nomenclature Committee of the Fleischner Society.
Radiology.
1996;200(2):327–331
2.
A.
McWilliams,
M.C.
Tammemagi,
J.R.
Mayo,
et al.
Probability of cancer in pulmonary nodules detected on first screening CT,
N.
Engl.
J.
Med.
369 (2013) 910–919.
3.
Wilson DO,
Weissfeld JL,
Fuhrman CR,
et al.
The Pittsburgh Lung Screening Study (PLuSS): outcomes within 3 years of a first computed tomography scan.
Am J Respir Crit Care Med.
2008; 178:956-61.
4....