Pulmonary nodules: causes and diagnosis
Written by:
Pulmonologist
Published: 21/03/2017
Edited by: Nicholas Howley
It can be frightening if the doctor tells you that you have a nodule in your lung. We asked leading respiratory physician Dr Amit Patel what causes lung nodules and how they are diagnosed.
A pulmonary (or lung) nodule is a rounded or elliptical growth on the lung. It is usually detected with a chest x-ray or scan. Modern scanners can detect pulmonary nodules which previously would have gone undetected by a chest x-ray.
The detection of a nodule always generates concern in the patient as generally is interpreted as being synonymous with a non-benign disease. A significant proportion of nodules are detected by chance and not because of any abnormal symptoms. The cause in the majority of cases is benign or harmless.
What are the causes of lung nodules?
There are a plethora of causes for nodules. They are often the result of previous or current infections. These nodules may well have been present for many years and are considered benign. Sometimes nodules can be cancerous and this of course needs further investigation. All nodules therefore do need careful review with a specialist.
How can lung nodules be diagnosed?
Usually the radiological characteristics of the lung nodule can guide diagnosis and this is carefully examined with specialist radiology colleagues. There is a balance to be struck between the need for a definitive diagnosis with risks of the invasive tests required for this. Often the nodule is too small to be easily sampled and a period of follow up with scans is arranged. If the nodule is large enough a biopsy can be arranged. The patient may also have further scans arranged. The diagnostic process involves many factors that are taken into consideration including the degree of concern and general health and well-being of the patient.