What does a nodule on my CT scan mean?

Nodules on the lungs are often discovered after a person undergoes a chest x-ray or CT scan, a procedure that produces detailed images of the lungs. These scans can be ordered for many reasons, from getting into a car accident to having trouble breathing.

“Commonly called a ‘spot on the lung’ or a ‘shadow,’ a lung nodule is a small abnormal area that is more dense than normal lung tissue,” says Dr. Davies Wong, a pulmonary disease specialist affiliated with Sharp Memorial Hospital. “The good news is that approximately 95% of pulmonary nodules are benign.”

These spots on a CT scan usually don’t cause symptoms and are often caused by scar tissue, autoimmune diseases, respiratory system infections, some irritant in the air, or even a healed infection that may have never caused an illness.

However, the other 5% of these nodules could be cancerous.

“Unfortunately, a CT scan is unable to show whether a nodule is benign or not,” says Dr. Wong. “It is important to be proactive about a nodule because earlier detection of lung cancer can make a huge difference in the outcome.”

What should you do if a nodule is found?

With such a large percentage of nodules being benign, the most important thing to do if a nodule is found after you have a scan is to have your physician actively monitor the nodule's growth over time. Nodules that stay the same size over a two-year surveillance are usually deemed not cancerous.

“Your physician should consider if there are other factors that could contribute to the nodule needing further testing as well,” says Dr. Wong.

Nodules that are large — typically greater than 8 millimeters — or ones that grow substantially over time may need further evaluation beyond just follow-up imaging. A specialist can evaluate the need for further testing based on your risk factors, such as:

• Your smoking history

• Your age

• Whether you have a family history of cancer

• Whether you have received radiation therapy to the chest

• Whether you have had exposure to asbestos, radon or second-hand smoke

The next step would likely be tests, biopsies and possibly, surgery or radiation, depending on the diagnosis.

Where can you go for care?

If a lung nodule is detected, your first step will be to discuss next steps with your primary care doctor. At Sharp Memorial, your doctor may refer you to the Outpatient Pulmonary Clinic for assistance in analyzing and treating a nodule.

The clinic offers a personalized experience to help patients understand their lung screenings and CT scans. If a nodule is found, the team of experts and a patient navigator monitor the nodule to ensure any lung cancer or conditions are identified early.

Hearing the words, “we found something,” can be stress-inducing for people getting a scan read from a doctor, but it is important to remember the big picture if a nodule is found.

“While most incidental nodules are at low risk of being cancerous, it is important to be an advocate for monitoring their growth,” says Dr. Wong. “This can lead to early mitigation of any disease progression and better outcomes overall."

Learn more about lung cancer; get the latest health and wellness news, trends and patient stories from Sharp Health News; and subscribe to our weekly newsletter by clicking the "Sign up" link below.