Lung Cancer

What is lung cancer?

Lung cancer arises from the uncontrolled growth of abnormal cells within one or both lungs. It often metastasises to other parts of the body before the cancer can be detected in the lungs.

Lung cancer is the 5th most commonly diagnosed cancer in Australia.

While smoking and older age are the main risk factors for lung cancer, the disease can also occur in non-smokers. In Australia, it is estimated that 16.1% of men and 28.9% of women diagnosed with lung cancer between 2017-2026 are non-smokers.

Some international studies suggest there is a global trend of rising diagnoses in non-smokers.

What are the types of lung cancer?

The 2 main types of lung cancer can be distinguished from the appearance of their cells under a microscope:

Non-small cell lung cancer

Non-small cell lung cancer (NSCLC): A group of lung cancers, including adenocarcinoma, squamous cell carcinoma and large cell carcinoma, that make up around 85-90% of diagnoses.

Small cell lung cancer

Small cell lung cancer: A fast-growing, less common type of lung cancer that begins in the middle of the lungs and spreads faster than NSCLC.

What are the common symptoms of lung cancer?

Symptoms of lung cancer tend to appear when the disease has progressed to a later stage and has already spread to other parts of the body.

Some common symptoms of lung cancer include:

A new or changed cough that lasts more than 3 weeks
Chest and/or shoulder pain that worsens when coughing or inhaling deeply
Coughing up any amount of blood
Breathing difficulties such as shortness of breath
Hoarse voice
Difficulty swallowing
Persistent chest infection
Unintentional weight loss
Loss of appetite
Fatigue

If the cancer has metastasised to other parts of the body such as the bones, brain and liver, it can cause the following symptoms:

Pain in the neck, back or hips
Changes in vision or speech
Swollen lymph nodes
Jaundice

It is important to note that having some of these symptoms does not necessarily mean that you have lung cancer. Many of these symptoms overlap with other diseases and/or are long-term effects of smoking. If these symptoms persist, you should see a GP as soon as possible, even if you have never smoked.

How is lung cancer diagnosed?

Unfortunately, patients are often diagnosed in advanced stages when the cancer has already spread. This can be attributed to the late emergence or vagueness of symptoms as well as stigma and lack of awareness.

There is currently no population-wide screening program in Australia for lung cancer, but there are a number of tests that can be used to diagnose lung cancer. These may include:

Imaging tests such as X-rays, CT scans and PET scans
Sputum cytology, where a sample of phlegm is examined under a microscope
Biopsy of abnormal lung cells via a bronchoscopy, mediastinoscopy or needle biopsy

When lung cancer is diagnosed, additional tests may be done to determine the stage of the cancer and whether it has spread to other parts of the body. This helps doctors develop the most effective treatment plan for the patient.

What is the prognosis for lung cancer?

Lung cancer is the leading cause of death from cancer in Australia and the rest of the world. The 5-year survival rate of 19% for all lung cancers means that, depending on the stage of their disease, just 1 in 5 people will survive the first 5 years following their diagnosis.

Emerging lung cancer researchers like Dr Mara Zeissig and Dr Venessa Chin are hoping to change this.