Lung nodule and Lung cancer service

Lung cancer is the most common cause of cancer. It is also the most common cause of death from cancer worldwide. This is because lung cancer is often diagnosed in the later stages after the disease has progressed and symptoms become more apparent. Thus, there is a great need to increase awareness of lung cancer risk factors and establish an early assessment and diagnosis pathway for such patients.

For patients who have been diagnosed with a lung nodule:

If a chest X-ray or CT scan finds a growth in the lung (lung nodule), then you may be referred to the East Melbourne Heart & Lung Clinic. Here we offer a service with an established pathway for patients with a newly diagnosed lung nodule needing urgent investigation and management.

We work closely in a multidisciplinary manner with respiratory physicians, thoracic surgeons, radiologists, pathologists, oncologists and radiotherapy specialists. All you will need is a referral from your provider and bring your scans to your clinic appointment. After a review of your scans we will organise any further relevant testing.

What are pulmonary nodules?

A pulmonary nodule is a small round or oval-shaped growth in the lung. It may also be called a “spot on the lung” or a “coin lesion.” Pulmonary nodules are smaller than 3cm in diameter. If the growth is larger than that, it is called a pulmonary mass and is more likely to represent a cancer than a nodule.

What causes pulmonary nodules?

There are two main types of pulmonary nodules: malignant (cancerous) and benign (noncancerous). The majority (>90%) of pulmonary nodules that are smaller than 2cm in diameter are benign.
There are a number of causes for benign nodules. Many are due to inflammation in the lungs as a result of an infection or more widespread inflammation. The nodule may represent an active problem or it may be due scar tissue from a previous inflammation. Causes of benign lesions include:

• Infections
• Non-infectious causes eg. Sarcoidosis, rheumatoid arthritis
• Neoplasms (benign or malignant)

What are the symptoms of pulmonary nodules?

Usually there are no symptoms but if present, symptoms would be related to the condition that caused the nodule to develop. If the nodule is due to lung cancer, the patient is often without symptoms or may have developed a new cough, or coughed up blood. Most of the time, a patient is unaware of the presence of a lung nodule until a chest X-ray or computed tomography scan (CT scan) of the lungs is performed and the nodule is picked up incidentally.

How common are pulmonary nodules?

Countless pulmonary nodules are found each year during chest X-rays or CT scans. Most nodules are noncancerous (benign). A solitary pulmonary nodule is found on up to 0.2% of all chest X-rays films. Lung nodules are more commonly found on more sensitive scans such as lung CT scans, where they are discovered upto 50% of the time. Risk factors for malignant pulmonary nodules include a history of smoking and older age.

How is the cause of pulmonary nodules diagnosed?

Though most lung nodules are not malignant, it is very important that nodules that could be cancerous are identified early on so that they can be removed at an early and curable stage.

What are the initial tests involved in investigating a lung nodule?

• Chest X-rays and CT Scans — Usually, the first sign that a pulmonary nodule is present is a spot on the lung that shows up on a chest X-ray or a CT scan. These tests are usually done when a person sees the doctor for a respiratory illness.

If the X-ray film or CT scan shows a spot on the lungs, your doctor will ask you about your medical history, including whether you have had cancer in the past. He or she will want to know whether you are a smoker or former smoker and about any exposure to environmental chemicals that may be toxic.

The doctor will look at the X-ray to evaluate the size and shape of the nodule, its location, and its general appearance. Nodules can be seen on a chest Xray if they are generally at least 8 to 10 millimeters in diameter. Smaller nodules will be difficult to see. Other factors that make a nodule look more cancerous are: the larger the nodule is, the more irregularly shaped it is, and those located in the upper portions of the lung.

You should bring in an old chest Xrays or CT scans so that your doctor can look at them to determine the growth rate of the nodule. In general, malignant nodules double in size every one to six months. Nodules with a slower or faster growth rate are less likely to be cancerous.

If your nodule was picked up by a chest x-ray, then you may be asked to undergo a CT scan to obtain a more detailed image of the nodule. CT scans can give information about the specific features of the nodule, including its shape, size, location and internal density. Additional, CT scans can identify very small nodules, as small as 1-2 mm in diameter.

If the nodule is too small to be sampled or if its features suggest a very low likelihood that it represents a cancer, your doctor may recommend to follow the nodule over time with repeated chest imaging. If the nodule size remains stable over a certain period of time, then it is confirmed to be benign. If a concerning pace of growth is noted, then additional evaluation would be suggested. The interval between scans and the length of follow-up depends on the size of the nodule and the risk of malignancy.

Other tests that may be required to further investigate your lung nodule:

• Positron emission tomography (PET) — A PET scan can also help to find out if a nodule is malignant or benign. A PET scan uses a radiolabeled substance such as glucose that is absorbed by the nodule, and provides a picture of the nodule’s metabolic activity level. Malignant cells have faster metabolic rates than normal cells, so they require more energy and thus absorb more of the radiolabeled substance. Nodules can light up on PET imaging if they are malignant or if there is active inflammation. We have to be careful with the PET scan interpretation when someone has nodules smaller than 8-10 mm because they are not seen well by PET imaging.
• Biopsy — A biopsy is a procedure in which a small tissue sample is removed from the nodule so it can be examined under a microscope. It may be performed when other tests are inconclusive to rule out the chance that a growth is malignant.

There are a few ways to obtain a sample of the lesion, short of going to surgery. The method used depends on the size and location of the nodule, as well as the comfort of the medical team with these procedures. Our expert respiratory physicians or thoracic surgeons perform the first two procedures, whilst a needle biopsy with CT guidance is undertaken by experienced radiologists.

• Bronchoscopy: This procedure is used if it appears the nodule can be reached through the breathing tubes. It uses a bronchoscope, which is a thin, lighted flexible tube that can be inserted into the mouth or nose and through the windpipe (trachea) into the bronchus (airway) of the lung. The bronchoscope has a very small camera at its end. Biopsy tools can be passed through the camera to reach the nodule. It is an outpatient procedure with a low risk profile generally.
• Linear or Radial EBUS (Endobronchial Ultrasound): This procedure is used when the nodule lies a bit deeper in the lung. It is similar to a bronchoscopy but a slightly thicker flexible tube is inserted into the mouth or nose and then through to the lungs. The nodule (or sometimes a lymph node) is identified using ultrasound and a sample is obtained specifically from the site of the nodule. This increases the likelihood of obtaining a result.
• Needle biopsy (also known as transthoracic needle aspiration): This test is most successful when the nodule is towards the edge of the lung, near the chest wall. A needle is inserted through the chest wall and into the nodule, usually under the guidance of a CT scan.

Surgical removal is reserved if the nodule has a very concerning appearance or growth pattern, or it is somewhat concerning and its nature is not able to be clarified by the above tests. This will diagnose the nature of the nodule while treating it at the same time. However, this requires the patient be fit enough to undergo the surgery.

How are pulmonary nodules treated?

If the pulmonary nodule is benign, it usually does not require treatment. If an active infection or a disease of inflammation in the body is found, then treatment would be based on the condition identified and the symptoms that are present.

If the nodule is malignant, there seems to be no spread of the cancer, and the patient is fit, then the cancer should be removed with surgery. If a non-surgical biopsy of a nodule with high concern for malignancy is done and the results are inconclusive, it is recommended that the nodule be taken out.

Surgical techniques to take out pulmonary nodules include:

Thoracotomy — This procedure is considered open lung surgery. A cut is made in the wall of the chest in order to remove pieces of diseased lung tissue. Patients usually have to remain in the hospital for a few days after the operation. The mortality risk is low.

Video-Assisted Thoracoscopy (VATS) — This procedure uses a flexible tube with a small camera on its end. This scope is inserted through a small cut into the chest wall. The camera allows the surgeon to view an image of the nodule on a screen. This technique needs a smaller cut and a shorter recovery time than a thoracotomy procedure.