A pulmonary nodule, or lung nodule, is a “spot” smaller than 2 centimeters that appears on an x-ray, CT scan, or other diagnostic imaging. Abnormalities larger than 2 cm are considered pulmonary “masses” instead of nodules. Pulmonary nodules are fairly common.
Types of Pulmonary Nodules
In many cases, a nodule is an abnormal but non-cancerous growth of tissue. These spots grow slowly, will not spread to other parts of the body, and usually do not require removal. The most common types of benign nodules are:
- Granulomas, which are clumps of inflamed tissue
- Hamartomas, which are benign lung tumors.
In some cases, presence of a nodule may indicate tuberculosis, an abscess, pneumonia, or an infection such as valley fever (c)occidioidomycosis. Valley fever is a fungal infection commonly seen in the desert regions of the southwestern U.S. It starts when fungal particles are inhaled into the lungs. On an x-ray, nodules caused by valley fever sometimes resemble cancer.
Another cause of lung nodules is inflammation from conditions such as rheumatoid arthritis, Wegener granulomatosis, and sarcoidosis.
Finally, some pulmonary nodules are malignant—cancer that originated in the lungs or that started in another part of the body and spread to the lungs. The likelihood of a lung nodule being cancerous depends on several factors. In people less than 35 years of age, there is about a 1% chance that the nodule is cancerous; in people over age 50, this chance rises to 50%.
Pulmonary nodules usually cause no symptoms and are frequently discovered when a patient has a chest x-ray or CT scan for another reason. When they do cause symptoms, however, those symptoms may include coughing, wheezing, shortness of breath, or, in the case of pneumonia, fever.
Benign pulmonary nodules usually have smoother edges, a more regular shape, a higher calcium content, a more consistent color, and a slower rate of growth than cancerous nodules. If your nodule appears to be benign, your physician may recommend monitoring it with regular x-rays, CTs, or other diagnostic tests. Nodules that remain the same size for at least two years are usually considered benign.
If your nodule appears to be caused by an infection, disease, or cancer, your physician may order one or more of the following tests:
- Blood work
- Tuberculosis skin test
- Lung imaging—CT, PET and/or MRI
- Biopsies obtained through a needle or a bronchoscopy.
Treatment of lung nodules varies widely depending upon the cause, and whether they result from infection, inflammation, cancer, or another condition. Most benign lung nodules, especially those that haven’t changed for several years, can be left alone.
At our Pulmonary Nodule Clinic, each patient’s nodule findings are reviewed by a multidisciplinary team made up of infectious disease specialists, pulmonologists, thoracic radiologists, thoracic surgeons, internal medicine specialists, and oncologists. The team develops a treatment plan for each patient, refers the patient to the appropriate specialist, and notifies the patient’s referring physician of the plan and treatment options.
Learn About Pulmonary Nodules Services at Norton Thoracic Institute
To learn more about the services offered by the Pulmonary Nodule Clinic at Norton Thoracic Institute, call (602) 406-7564.