This document discusses solitary pulmonary nodules and provides information about their evaluation and management. It defines a solitary pulmonary nodule as an asymptomatic lesion less than 3 cm surrounded by normal lung tissue. The most common benign causes include granulomas and hamartomas, while the most common malignant causes are adenocarcinomas and squamous cell carcinomas. CT is useful for evaluating solitary pulmonary nodules to characterize them and guide biopsy. Features like size, borders, density, calcification and doubling time provide clues about whether a nodule is likely benign or malignant.

1. Solitary Pulmonary Nodule
Dr LNR González
Department of Internal Medicine
Kimberley Hospital Complex
2012

2. Solitary Pulmonary Nodule
Is it cancer?
A solitary pulmonary nodule is an
asymptomatic lesion less than 3 cm in
diameter surrounded by normal lung
parenchyma that is incidentally found on a
chest radiograph or computed tomography
(CT)
Goldman: Goldman's Cecil Medicine, 24th ed.

3. 3

4. 4
Common Etiologies of Solitary Pulmonary Nodules
Benign
Nonspecific granuloma (15 to 25 percent)
Hamartoma (15 percent)
Infectious granuloma (15 percent)
Aspergillosis
Coccidioidomycosis
Cryptococcosis
Histoplasmosis
Tuberculosis
Malignant
Adenocarcinoma (47 percent)
Squamous cell carcinoma (22 percent)
Metastasis (8 percent)
Non–small cell carcinoma (7 percent)
Small cell carcinoma (4 percent)
NOTE: Percentage denotes frequency of these benign or malignant lesions.
Am Fam Physician. 2009;80(8):827-831, 834.

5. 5
•
SIMULANTS OF A SOLITARY
PULMONARY MASS
•
Extrathoracic artefacts
•
Cutaneous masses
•
Bony lesions
•
Pleural tumours or plaques
•
Encysted pleural fluid
•
Pulmonary vessels
Adam: Grainger & Allison's Diagnostic Radiology, 5th ed.2008

6. 6
•
In up to 20% of instances, a “lung nodule”
visible on chest radiographs actually
represents an artifact, chest wall lesion, or
pleural abnormality
Mason: Murray and Nadel's Textbook of Respiratory Medicine, 5th ed.2010

7. 7
Assessment of a solitary pulmonary nodule (SPN) seen on chest
radiographs is a
common indication for CT
 CT is used to confirm that the SPN is real.
 To confirm that the SPN is solitary.
 To attempt further noninvasive characterization of the lesion.
 To guide percutaneous biopsy of the lesion.
 To provide staging information if the SPN is found to represent a carcinoma
.
Mason: Murray and Nadel's Textbook of Respiratory Medicine, 5th
ed.2010

8. 8
Radiologic Features Suggestive of Benign or Malignant Solitary Pulmonary Nodules
Radiologic
feature Benign Malignant
Size < 5 mm > 10 mm
Border Smooth Irregular or spiculated
Density Dense, solid Nonsolid, “ground glass”
Calcification Typically a benign feature, especially in “concentric,”
“central,” “popcorn-like,” or “homogeneous” patterns
Typically noncalcified, or
“eccentric” calcification
Doubling time Less than one month; more than one year One month to one year
Am Fam Physician. 2009;80(8):827-831, 834.

9. 9Solitary calcified granuloma.
Mettler: Essentials of Radiology, 2nd ed.

10. 10
Contrast-enhanced CT for the evaluation of a solitary pulmonary nodule.
There is differential enhancement in this lesion that was due to a primary
adenocarcinoma.
Mettler: Essentials of Radiology, 2nd ed.

11. 11
Mason: Murray and Nadel's Textbook of Respiratory Medicine, 5th ed.
Thoracic CT of bronchogenic carcinoma.
Axial CT displayed in lung windows shows
a spiculated lesion within the left upper lobe.

12. 12Mason: Murray and Nadel's Textbook of Respiratory Medicine, 5th ed.
CT scan of a proven hamartoma shows a well-marginated nodule in which there is
evidence of intratumoral fat and calcification.
This combination is characteristic but occurs in only about a fourth of cases.

13. 13

14. 14

15. 15

16. 16

17. 17
(A) CT image showing ground-glass
nodule in right upper lobe of the lung. (B)
Follow-up scan of the same patient 20
months later reveals progression to a
mixed ground-glass/solid tumor. VATS
confirmed that the lesion was malignant
(adenocarcinoma).
©2006 MGH Department of Radiology

18. 18

19. 19
Only 2 findings are
considered to be sufficient to
preclude further evaluation:
calcification in a benign
pattern
and
stability in size for more
than 2 years.
J Am Coll Radiol 2007;4:152-155.
Copyright

20. 20
Goldman: Goldman's Cecil Medicine,
24th ed.
*Patient with a minimal or absent history of smoking and other known risk factors for the development
of lung cancer and a nodule 8 mm or smaller in size.
†Patient with a history of smoking and other risk factors for the development of lung cancer and a
nodule 8 mm or larger in size.

21. 21
The End