A pulmonary nodule is a more or less rounded image, smaller than 3 cm, (if larger it is called a mass), detected by radiology. In the past, the pulmonary nodule was detected by chest X-ray, whereas nowadays it is also detected by scanner (CT).
The pulmonary nodule may be solitary or there may be more than one. In the scanner we can visualize nodules of 2-3 mm and in the chest X-ray from 10 mm, although depending on the location they can go unnoticed, except for nodules with calcium which are detected even subcentimetrically.
The frequency with which chest CT scans are performed means that pulmonary nodules are very frequent findings, causing alarm and prompting medical consultation. Nodules located in the lower part of the lungs are also detected in the abdominal scan.
In order for the Pneumology specialist to assess the pulmonary nodule it is important:
- The morphology: rounded, polygonal, smooth contour, blurred contour or spiculated contour.
- Density: solid, “ground glass”, calcification, fat, homogeneity…
- The location and whether it is single or multiple
- The patient’s medical history, such as whether he/she has smoked or has had cancer.
- The size of the nodule at onset and subsequent evolution.
Causes of pulmonary nodule
Benign pulmonary nodule is the most common type of pulmonary nodule. It is mainly secondary to scarring, mucus plugs inside the bronchus and infections. The prevalence of pulmonary nodules in asymptomatic smoking subjects is up to 66%, most of them being benign in nature up to 99%.
If we talk about malignant pulmonary nodule, another large group of causes are neoplastic, due to cancer, either of pulmonary origin or of origin in another organ and that has spread to the lung.
Pulmonary nodule: symptoms
The pulmonary nodule is, in general, asymptomatic since they are usually an incidental finding. However, a pulmonary nodule of infectious cause may give symptoms such as pain or fever.
Treatment for pulmonary nodule
Depending on the medical history, such as smoking or previous neoplastic disease, and the characteristics of the pulmonary nodule, it may be prudent to perform a follow-up scan after three to six months to see if the pulmonary nodule grows, remains stable or disappears.
When the pulmonary nodule grows or does not disappear, the following actions can be taken:
- From 7-10 mm, Pet-Tac can be performed if the suspicion is relatively high, although there are also false positives and false negatives.
- If it is a central nodule, Bronchofibroscopy can be performed.
- If a peripheral malignant pulmonary nodule is suspected with a size that allows it, a scanner-guided biopsy puncture can be performed.
Treatment varies depending on the type of pulmonary nodule:
- If benign scarring, nothing needs to be done.
- If it is benign inflammatory/infectious, it can be treated with antibiotics.
- If it is malignant or highly suspicious of malignancy and is not spread to lymph nodes or other regions, it should be operated on.
- If it is doubtful such as the so-called “ground glass” nodules which may be benign or malignant depending on their evolution, close monitoring for possible malignancy should be performed.