Lung nodules

A lung nodule is a round area that is denser than the normal lung tissue seen on a chest x-ray or CT scan. They are very common and can be present in up to half of all adults' chest scans. Small nodules do not cause any symptoms.


Causes of lung nodules

Most nodules are caused by:

  • scar tissue
  • a healed infection
  • an irritant from the air.

For a small number of people, a nodule is an early-stage lung cancer.

Cancer is more likely if you:

  • are older than 50 years
  • have a larger nodule
  • smoke or have smoked
  • have other cancer risks, such as lung cancer in your family or having handled asbestos in the past.

But even if you have a higher risk of lung cancer, most small nodules are not lung cancer. And if a nodule turns out to be lung cancer, it is likely to be an early-stage lung cancer and therefore curable.


Symptoms of lung nodules

In most cases a lung nodule will not cause any symptoms. But if the nodule is larger, or caused by cancer, you may have:

  • a cough that does not go away
  • dull or sharp chest pain
  • shortness of breath
  • frequent lung infections
  • wheezing.

Contact your healthcare provider if you:

  • cough up blood or have a cough that changes or gets worse
  • develop new shortness of breath, chest pain, fevers or chills
  • lose weight without trying
  • are worried about the nodule.

Diagnosing lung nodules

Let your healthcare provider know if you have ever had a chest x-ray or CT scan. It is very useful to know if your nodule is the same size as it was on past imaging.

To help decide the cause of a nodule, your healthcare provider will see:

  • how it looks on the CT scan
  • whether it has grown over time.

If concerned, they will take a sample (biopsy) of the nodule with a needle or surgery. Most people with a nodule will not need to have this test.


Treating lung nodules

For most nodules, your healthcare provider may recommend getting more CT scans in the future. This is to see if the nodule changes over time. This is called active surveillance.

If a nodule is not cancer, it usually will not grow bigger. If the nodule does not grow over 2 years, it is very unlikely to be cancer.

If the nodule is getting bigger, it needs to be looked at more closely to see if it is lung cancer. This will be done using different types of scans or by taking a sample (biopsy) with a needle or by surgery.