It is a spot where an abnormal tissue that has been found in the lung. This is usually discovered on a routine chest X-Ray taken or when you have a CT scan of your lung taken for other reasons.
Pulmonary nodules may be cause by a scar in the lung (from an old infection), a chronic infection like tuberculosis, an abnormal blood vessel, a benign growth or a congenital lung abnormality.
In our specialist clinic, we see many cases of lung nodules referred by family doctors or other specialists. The first thing the respiratory physician will do is to review the patients’ all previous X-rays or CT scan.
If the nodule has been there for several years, and has not changed in size or appearance, it is unlikely to be a cancer. If there are no previous X-rays for comparison, or the nodule has changed in size and appearance, a CT scan or PET/CT of the lungs will be useful for further evaluation.
If the nodule is very small (equal or less than 5mm), a biopsy is not accurate and a repeat the CT again in about 3 months to assess the progress of the nodule is warranted.
If the nodule is at least 10mm, a biopsy can be done to assess whether it is cancerous or not. A biopsy is when a tissue specimen from the nodule is examined under the microscope. There are several ways a biopsy can be performed. It depends mainly on the size and location of the nodule.
A common way of obtaining a biopsy specimen is through a bronchoscopy. This is when a thin, flexible tube with a camera attached is inserted into the airways. This is commonly done when the nodule is centrally located and close to the main airways. If the nodule is at the edge of the lungs, a radiologist will be required to do a needle biopsy thorough the skin. During this procedure, a long and thin needle is inserted into the chest under CT scan guidance to obtain a sample of the nodule.
On some occasions, when the nodule appearance is very suggestive of cancer, a keyhole surgery by the cardiothoracic surgeon to remove the entire nodule may be most appropriate way of biopsy.