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 a CT scan, a procedure that produces detailed images of the lungs. These scans can be ordered for many reasons, from a car accident to 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 often result from scar tissue, autoimmune diseases, respiratory infections, air irritants, or even a healed infection that may never have caused 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 period 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 that grow substantially over time may need further evaluation beyond follow-up imaging. A specialist can evaluate the need for further testing based on your risk factors, such as:

• Smoking history

• Age

• A family history of cancer

• Past radiation therapy to the chest

• 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 primary care doctor can explain the finding and recommend next steps. 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 other conditions are identified early.

Hearing a doctor say, “we found something,” can be stress-inducing, but it's 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.