What is a Pulmonary Nodule?
It is a small growth in the lung that ranges from 0.5 – 2 cm. Any larger would be a pulmonary mass which has a higher chance of being cancerous.
Doctors usually compare imaging tests of these nodules over some time to see if there is an increase in number or size to determine if it is cancerous.
These nodules are hardly detected, reportedly only being found in 1% of X-rays and 30% of CT scans.
Causes of Pulmonary Nodules
There are two main types of pulmonary nodules. Benign nodules (non-cancerous) or malignant nodules which are determined by multiple features, including the size, shape, characteristic and content within the growth.
Benign nodules can be caused by infections from diseases such as tuberculosis or fungal infections or may be the result of scarring from previous infections. Other chronic illnesses such as rheumatoid arthritis may also lead to infections that form tumours. Lastly, fibrous growths which are the uncontrolled growth of fibrous tissues in the lungs may also lead to lung nodules.
Cancerous nodules can form due to a variety of cancers from primary lung cancer to cancer that has metastasized from other parts of the body.
Symptoms of Pulmonary Nodules
They are usually asymptomatic (without symptoms) and commonly picked up when patients go for screening. Ocassionally, they manifest in a persistent cough that does not go away despite patients having sought treatment.
Pulmonary nodules will commonly show up as a spot in chest X-rays if they are larger than 1cm in diameter. As a result, it is only commonly discovered when patients are checking for other respiratory conditions.
In recent years, CT scans are becoming a common method of screening for such illnesses. At ICTS, we offer a screening package which involves a low dose non-contrast CT scan that can pick up nodules as small as 5mm in diameter. These nodules will be accessed over some time to examine if they grow in size or multiply in numbers. This will allow the detection of cancerous nodules.
Once a cancerous nodule has been confirmed either via a CT scan or a biopsy, the PET CT scan is used to evaluate metabolic activity levels. A cancerous nodule would require more resources to grow and thus it operates at a higher metabolic level. The PET CT scan will light up in these areas thus pinpointing the location of these cancerous nodules.
A needle directed by the guidance of a CT scan will be inserted into the nodule to obtain a sample of tissue. This tissue will later be sent for testing of any abnormal activity. This will help Dr Aneez determine if the nodule is cancerous.
This procedure involves the use of the bronchoscope – a flexible tube with a camera attached to it.
It will be guided from the mouth into the airways to then carry out a biopsy.
This advanced procedure makes use of a navigational guidance system that targets nodules of similar sizes to achieve accurate sampling of tissues. They are also used in targeting a nodule for dye marking pre-operatively before proceeding to surgery to resect the nodule accurately.
For benign nodules, no treatment would be required. However, if it is due to an active infection, that problem will be assessed and treated accordingly.
If the patient is unable to get a conclusive diagnosis despite having undergone a biopsy, an excision biopsy will be recommended to remove the nodule via surgical methods. At ICTS, minimally invasive surgical options are preferential.
The first is video-assisted thoracic surgery. This will occur via 2-3 keyhole incisions in the chest to facilitate faster recovery. The nodule will then be removed.
This procedure is performed from a robotic platform and would be able to give the surgeon more precision in the surgery. A special marking dye is used to further pinpoint the location for incision which allows for smaller cuts and shorter recovery times.
This is the traditional form of open lung surgery whereby an incision is made in the chest wall for the surgeon to remove the nodule. As this form of surgery is more invasive, it requires a longer hospitalisation period along with longer recovery time.