Symptoms

• According to the University of Rochester Medical Center, 90 percent or more of all pulmonary nodules are discovered incidentally on a chest x-ray or CT scan which was performed for other reasons. There are often no symptoms, or symptoms may be similar to a mild flu or chest cold.
  
  

Nodule Facts

• Nodules are three centimeters in diameter or smaller. Anything larger is considered to be a mass. Small, non-cancerous nodules may not require treatment; however, if the nodule changes size or is new, your doctor will likely order additional testing.
  
  

Diagnosis

• CT (computerized tomography) scans, PET (positron emission tomography) scans and tissue biopsies may be used to determine if the pulmonary nodule is cancerous or benign.
  
  

Significance

• According to Medline Plus, less than half of all nodules are cancerous; however, if the nodule is malignant, it is crucial that the nodule is properly diagnosed as soon as possible. Cancerous nodules often grow quickly.
  
  

Causes

• Benign pulmonary nodules are usually wounds that have healed either from a fungal infection or tuberculosis. Other causes may include hematoma, lung cysts and vascular irregularities.