Lung nodules: a guide for patients

What is a lung nodule?

A lung nodule, also known as a pulmonary nodule, is a small lump detected on an X-ray or CT scan of the chest. A lung nodule shows up as a white spot, up to 30mm across, on a black background of normal lung.

Most lung nodules do not cause symptoms.

Are lung nodules common?

Yes. Nodules are found in up to 35 in every 100 people who have a CT scan which includes their lungs.

Sometimes people have more than one lung nodule. Having more nodules may not be more serious than having one nodule.

What causes lung nodules?

Lung nodules have lots of different causes. These include:

  • infection
  • old tuberculosis (TB)
  • scarring
  • a normal gland in the lung such as a lymph node

Sometimes a lung nodule can be the first sign of a cancer in the lung. Finding a lung nodule earlier means it is potentially more treatable.

What do you look for in scans?

Doctors and specialist nurses assess the size of a nodule and its appearance to decide if it needs follow-up or further assessment.

We use national guidelines written using evidence from clinical studies of thousands of people’s scans. We also consider things such as your age and medical history.

Together, this information helps us decide what to do next with each nodule and to pick out any that may need follow-up.

What happens after scans?

If you have a scan that shows a lung nodule, a multidisciplinary team (MDT) works together to look after you.

The team includes specialist radiologists, respiratory physicians and surgeons.

Follow-up scans

It is not always possible to diagnose a nodule on the first scan. We may offer you one or more follow-up scans to see if the nodule changes over time.

Most lung nodules stay the same size, get smaller, or even disappear. If the nodule has not increased in size over the course of several scans, no more follow-ups are needed.

The process of repeated scans and reviewing results is sometimes called ‘nodule surveillance’ or ‘active monitoring’.

Your multidisciplinary team (MDT) will assess your results after each scan.

Other tests

A small number of people may need other tests after having CT scans including more specialist imaging investigations and a biopsy where a tiny sample of tissue is taken from the lungs and examined under a microscope.

Your doctor or specialist nurse will talk to you about your individual risk.

Follow-up appointments

Appointments to discuss the results of scans and the next steps are usually with a respiratory doctor or specialist nurse. These may be by phone, video or in person.

If you do have concerns, particularly between appointments, please email the lung nodules MDT at

You can find more information about lung nodules on the RM Partners West London Cancer Alliance website.