Since 1995 - Non Profit Healthcare Advice

Nodule on the lung

09/27/2005

Question:

an xray showed a nodule on the lung-what excatly does this mean and what are the possible diagnosis

Answer:

A nodule detected on a chest radiograph is an opacity, an area of solid tissue, surrounded by normal air-filled lung tissue.  It is an abnormal finding that can be caused by many different things.  The most concerning of which is lung cancer.  Other possibilities include infections, scarring, or exposures. 

Several clinical factors help in determining the possible causes of a nodule:  is or has the individual ever been a smoker?  is there a history of lung infections?  has the individual been exposed to any chemicals, dusts, or fumes?

Other important factors are the size, shape, and contours of the nodule on the chest x-ray.  Additionally, it is very important to know how long the nodule has been present-a new nodule (not present on previous x-rays) is more ominous than one that has been present previously.  If a nodule does not change in size, shape, or contour for a period of 24 months, it is usually considered benign (not cancerous).

Usually the detection of a nodule, requires further testing.  Obtaining any previous x-rays for comparison is always important.  A CT scan may be obtained to better image the nodule and determine if there are any other nodules present that were not detected by the x-ray.

Another test that may be performed is a PET scan, where a medicine is injected into a vein in the arm and images of the chest and body are obtained.  If the nodule is caused by a cancer, the medicine is concentrated in the nodule and shows up as a dark spot on the images.  If the lesion is not cancerous, no dark spot is seen.  The size and location of the nodule can limit the usefulness of this test and it is not 100% accurate.

Depending upon the results of the further tests, a biopsy may be required.  A biopsy is a sampling of the tissue within the nodule to determine the precise cause of the nodule.  Sometimes when the nodule has a very high likelihood of being cancerous, it is removed surgically without a biopsy.

You should discuss the chest x-ray finding of a nodule with your physician and decide if further testing or evaluation is needed.  You may want to seek further consultation with a doctor who specializes in diseases of the chest, a pulmonologist.

 

For more information:

Go to the Lung Center health topic.