Monday, May 25, 2015
More Than One Nodule
I just got the results of my CT scan and they found two 3mm nodule in my right lung. Does that fact I have more than one increase the chance of it being cancer?
A nodule in the lungs may be secondary to infection, scar, granuloma or tumor. In the Midwest US, a benign fungal infection known as histoplasmosis, is a common cause of these nodules. Depending on the risk factors such as age, smoking status, family history, etc. we determine the likelihood of these nodules being a malignant process. When suspicion for malignancy is high or when we are not sure about the diagnosis, a biopsy is usually carried out.
A scar will remain unchanged with time. An infection may continue to grow or disappear over time. A cancer or tumor usually will also grow but at a slower rate than infection. A nodule that is less than 10mm is too small to biopsy or diagnose with a body imaging such as PET scan. In these case we prefer to obtain serial CT scans in 3-6 month intervals to determine if the lesion is growing. Depending on your risk factors (as mentioned above) your physician will determine the likelihood of this being a cancer.
Just because you have more than one 3 mm nodule does not mean that it is cancer. Also, they are too small to get any diagnostic tissue at this time. The best approach in your case will be to discuss and review the CT scan and your history with a pulmonologist to determine when a repeat CT should be scheduled.
Shaheen Islam, MD, MPH
Clinical Associate Professor
Pulmonary, Allergy, Critical Care & Sleep
College of Medicine
The Ohio State University