Solitary pulmonary nodule
A solitary pulmonary nodule is a round or oval spot (lesion) in the lung that is seen with a chest x-ray or CT scan .
Chest x-ray
A chest x-ray is an x-ray of the chest, lungs, heart, large arteries, ribs, and diaphragm.
CT scan
A computed tomography (CT) scan is an imaging method that uses x-rays to create pictures of cross-sections of the body. Related tests include:Abdomin...
Causes
More than half of all solitary pulmonary nodules are noncancerous (benign). Benign nodules have many causes, including scars and past infections.
Infectious granulomas (which are formed by cells as a reaction to a past infection) cause most benign lesions. Common infections that often result in granulomas or other healed scars include:
Granulomas
Granulomatosis with polyangiitis (GPA) is a rare disorder in which blood vessels become inflamed. This leads to damage in major organs of the body. ...
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Tuberculosis
(TB) or exposure to TB
Tuberculosis
Pulmonary tuberculosis (TB) is a contagious bacterial infection that involves the lungs. It may spread to other organs.
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Fungus, such as
aspergillosis
,
coccidioidomycosis
,
cryptococcosis
, or
histoplasmosis
Aspergillosis
Aspergillosis is an infection or allergic response due to the Aspergillus fungus.
Coccidioidomycosis
Valley fever is an infection that occurs when the spores of the fungus Coccidioides immitis enter your body through the lungs.
Cryptococcosis
Cryptococcosis is infection with the fungi Cryptococcus neoformans and Cryptococcus gattii.
Histoplasmosis
Histoplasmosis is an infection that occurs from breathing in the spores of the fungus Histoplasma capsulatum.
Primary lung cancer is the most common cause of cancerous (malignant) pulmonary nodules. This is cancer that starts in the lung.
Symptoms
A solitary pulmonary nodule itself rarely causes symptoms.
Exams and Tests
A solitary pulmonary nodule is most often found on a chest x-ray or chest CT scan . These imaging tests are often done for other symptoms or reasons.
Chest CT scan
A chest CT (computed tomography) scan is an imaging method that uses x-rays to create cross-sectional pictures of the chest and upper abdomen....
Your doctor must decide whether the nodule in your lung is most likely benign (not cancer) or of concern. A nodule more likely benign if:
- The nodule is small, has a smooth border, and has a solid and even appearance on an x-ray or CT scan
- You are young and do not smoke
Your doctor may then choose to monitor the nodule over time by repeating a series of x-rays or CT scans.
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Repeat chest x-rays or chest CT scans are the most common way to monitor the nodule. Sometimes, lung
PET scans
may be done.
PET scans
A lung positron emission tomography (PET) scan is an imaging test. It uses a radioactive substance (called a tracer) to look for disease in the lung...
- If repeated x-rays show that the nodule size has not changed in 2 years, it is most likely benign and a biopsy is not needed.
Your doctor may choose to biopsy the nodule to rule out cancer if:
- You are a smoker
- You have other symptoms of lung cancer
- The nodule has grown in size or has changed when compared to earlier images
A lung needle biopsy may be done by placing a needle directly through the wall of your chest, or during procedures called bronchoscopy or mediastinoscopy .
Lung needle biopsy
A lung needle biopsy is a method to remove a piece of lung tissue for examination. If it is done through the wall of your chest, it is called a tran...
Bronchoscopy
Bronchoscopy is a test to view the airways and diagnose lung disease. It may also be used during the treatment of some lung conditions.
Mediastinoscopy
Mediastinoscopy with biopsy is a procedure in which a lighted instrument (mediastinoscope) is inserted in the space in the chest between the lungs (m...
Tests to rule out TB and other infections may also be done.
Treatment
Ask your doctor about the risks of having a biopsy versus monitoring the size of the nodule with regular x-rays or CT scans. Treatment may be based on the results of the biopsy or other tests.
Outlook (Prognosis)
The outlook is usually good if the nodule is benign. If the nodule does not grow larger over a 2-year period, often nothing more needs to be done.
References
Gotway MB, Panse PM, Gruden JF, Elicker BM. Thoracic radiology. In: Broaddus VC, Mason RJ, Ernst JD, et al, eds. Murray and Nadel's Textbook of Respiratory Medicine . 6th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 18.
Gould MK, Donington J, Lynch WR, et al. Evaluation of individuals with pulmonary nodules: when is it lung cancer? Diagnosis and management of lung cancer, 3rd ed: American College of Chest Physicians evidence-based clinical practice guidelines. Chest . 2013;143(5 Suppl):e93S-120S. PMID: 23649456 www.ncbi.nlm.nih.gov/pubmed/23649456 .
Ost DE, Gould MK. Decision making in patients with pulmonary nodules. Am J Respir Crit Care Med . 2012;185(4):363-372. PMID: 21980032 www.ncbi.nlm.nih.gov/pubmed/21980032 .
Padley SPG, Lazoura O. Pulmonary neoplasms. In: Adam A, Dixon AK, Gillard JH Schaefer-Prokop CM, eds. Grainger & Allison's Diagnostic Radiology: A Textbook of Medical Imaging . 6th ed. Philadelphia, PA: Elsevier Churchill Livingstone; 2015:chap 15.
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Adenocarcinoma - chest X-ray - illustration
This chest x-ray shows adenocarcinoma of the lung. There is a rounded light spot in the right upper lung (left side of the picture) at the level of the second rib. The light spot has irregular and poorly defined borders and is not uniform in density. Diseases that may cause this type of x-ray result would be tuberculous or fungal granuloma, and malignant or benign tumors.
Adenocarcinoma - chest X-ray
illustration
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Pulmonary nodule - front view chest X-ray - illustration
This x-ray shows a single lesion (pulmonary nodule) in the upper right lung (seen as a light area on the left side of the picture). The nodule has distinct borders (well-defined) and is uniform in density. Tuberculosis (TB) and other diseases can cause this type of lesion.
Pulmonary nodule - front view chest X-ray
illustration
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Pulmonary nodule, solitary - CT scan - illustration
This CT scan shows a single lesion (pulmonary nodule) in the right lung. This nodule is seen as the light circle in the upper portion of the dark area on the left side of the picture. A normal lung would look completely black in a CT scan.
Pulmonary nodule, solitary - CT scan
illustration
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Respiratory system - illustration
Air is breathed in through the nasal passageways, travels through the trachea and bronchi to the lungs.
Respiratory system
illustration
-
Adenocarcinoma - chest X-ray - illustration
This chest x-ray shows adenocarcinoma of the lung. There is a rounded light spot in the right upper lung (left side of the picture) at the level of the second rib. The light spot has irregular and poorly defined borders and is not uniform in density. Diseases that may cause this type of x-ray result would be tuberculous or fungal granuloma, and malignant or benign tumors.
Adenocarcinoma - chest X-ray
illustration
-
Pulmonary nodule - front view chest X-ray - illustration
This x-ray shows a single lesion (pulmonary nodule) in the upper right lung (seen as a light area on the left side of the picture). The nodule has distinct borders (well-defined) and is uniform in density. Tuberculosis (TB) and other diseases can cause this type of lesion.
Pulmonary nodule - front view chest X-ray
illustration
-
Pulmonary nodule, solitary - CT scan - illustration
This CT scan shows a single lesion (pulmonary nodule) in the right lung. This nodule is seen as the light circle in the upper portion of the dark area on the left side of the picture. A normal lung would look completely black in a CT scan.
Pulmonary nodule, solitary - CT scan
illustration
-
Respiratory system - illustration
Air is breathed in through the nasal passageways, travels through the trachea and bronchi to the lungs.
Respiratory system
illustration
Review Date: 8/1/2015
Reviewed By: Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital, Boston, MA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.