Overview

Understanding lung cancer

Lung cancer is a malignant tumour that forms in the tissue of one or both lungs. This tumour can originate in the bronchi or the spongy lung tissue. As it grows, it invades functional parts of the lung, affecting breathing, causing pain, and leading to other symptoms related to reduced lung function. These cancerous cells multiply uncontrollably and, without treatment, can spread throughout the body.

Often, the early symptoms of lung cancer are non-specific, which can make early diagnosis and treatment more challenging.

Symptoms of lung cancer

The symptoms of lung cancer can be similar to other diseases such as chronic obstructive pulmonary disease (COPD), chronic heart failure, and coronary heart disease. 

It’s important to investigate any of the following symptoms that last for more than three weeks, or earlier in patients with known risk factors or more than one of these signs:

• New or changed cough 
• Coughing up blood 
• Chest and/or shoulder pain 
• Shortness of breath 
• Hoarseness 
• Difficulty swallowing 
• Weight loss or loss of appetite 
• Persistent or recurrent chest infection 

Other symptoms of lung cancer include:

• Fatigue 
• Deep Vein Thrombosis  
• Abnormal chest signs  
• Finger clubbing  
• Cervical and/or supraclavicular lymphadenopathy  
• Features suggestive of lung cancer metastasis (e.g. brain, bone, liver or skin)  
• Pleural effusion  
• Thrombocytosis 

Risk factors

There are several risk factors associated with lung cancer.

• Lifestyle factors: Current or past tobacco smoking is the greatest risk factor.
• Environmental or occupational factors: Exposure to passive smoking. Occupational exposure to radon, asbestos, diesel exhaust, or silica. Exposure to air pollution.
• Personal factors:
  • Increasing age 
  • Family history of lung cancer in close relatives 
  • History of chronic lung disease, including COPD and pulmonary fibrosis
  • History of cancer, including lung cancer, head and neck cancer, and bladder cancer.
  • History of radiation therapy to the chest for other cancers 
  • HIV infection 
  • Certain gene mutations.

Cancer Australia provides detailed information about the various factors that increase the risk of lung cancer and how much they might increase that risk in their resource.

Australian guidelines recommend further investigation for any cough that lasts three weeks or longer. It’s crucial to urgently investigate persistent symptoms, especially in people who have known risk factors for lung cancer.

Guide to investigating symptoms

For general practitioners, it can be challenging to link a common symptom like a persistent cough to possible lung cancer in patients who don’t have many of the typical risk factors. 

Cancer Australia has developed a guide for healthcare professionals called Investigating symptoms of lung cancer.

This tool is designed to help all healthcare professionals assess patients with suspected lung cancer and ensure they are referred quickly into the diagnostic pathway. This guide is based on the best available evidence with expert consensus, and is supported by Lung Foundation Australia and many other professional organisations.

Lung Foundation Australia supports the use of evidence-based approaches for diagnosing and treating lung cancer. We encourage healthcare professionals to use reliable and up-to-date information. The following organisations publish guidelines, resources, and care pathways for lung cancer, and some also offer education for health professionals:

• Australia New Zealand Lung Cancer Nurses Forum
• Cancer Australia
• Cancer Council
• Cancer Institute NSW
• EviQ
• Thoracic Oncology Group of Australasia (TOGA)
• Thoracic Society of Australia and New Zealand (TSANZ)
• Cancer Nurses Society of Australia (CNSA)
• Australian Government Department of Health, Disability and Ageing

Sources:

1. Australian Institute of Health and Welfare. “Cancer data in Australia – Lung Cancer” (2024). Web report, last updated 9 Dec 2024.