Lung cancer is a serious disease that occurs when abnormal cells in the lungs begin to grow uncontrollably. It is one of the most common cancers and can affect both smokers and people who have never smoked.
In many cases, lung cancer does not cause obvious symptoms during its early stages. As the disease progresses, however, symptoms may become more noticeable. Early detection is important because treatment is generally more effective when the cancer is found before it spreads.
Symptoms of Lung Cancer
Lung cancer may not produce noticeable symptoms at first. When symptoms develop, they can include:
* A persistent or worsening cough
* Coughing up blood
* Persistent shortness of breath
* Unexplained tiredness or weakness
* Unexplained weight loss
* Chest pain or an ache, particularly when breathing or coughing
* Repeated chest infections
* Hoarseness or changes in the voice
* Loss of appetite
* Difficulty swallowing
Having these symptoms does not necessarily mean someone has lung cancer, as many can be caused by other conditions. However, persistent or unusual symptoms should be discussed with a doctor.
Causes of Lung Cancer
Smoking is the leading cause of lung cancer. Cigarette smoke contains numerous harmful chemicals that can damage cells in the lungs over time. The longer and more heavily a person smokes, the greater their risk.
However, lung cancer can also occur in people who have never smoked.
Other factors that can increase the risk include:
* Exposure to second-hand smoke
* Exposure to substances such as asbestos and certain chemicals
* Air pollution
* Previous radiation treatment to the chest
* A family history of lung cancer
* Increasing age
Having a risk factor does not mean a person will definitely develop lung cancer.
Types of Lung Cancer
Lung cancer that starts in the lungs is known as primary lung cancer. Cancer that begins somewhere else in the body and later spreads to the lungs is called secondary lung cancer.
There are two major types of primary lung cancer.
Non-small-cell lung cancer
Non-small-cell lung cancer is the most common type, accounting for roughly 80% to 85% of cases. It includes several forms, such as adenocarcinoma, squamous cell carcinoma and large-cell carcinoma.
Small-cell lung cancer
Small-cell lung cancer is less common but tends to grow and spread more quickly than non-small-cell lung cancer.
The specific type of lung cancer a person has plays an important role in determining the most appropriate treatment.
Diagnosis of Lung Cancer
Doctors may begin by asking about a person’s symptoms, smoking history and general health. If lung cancer is suspected, several tests may be carried out.
These can include a chest X-ray or CT scan to look for abnormalities in the lungs.
A biopsy may also be performed. During a biopsy, a sample of abnormal tissue is collected and examined in a laboratory to determine whether cancer cells are present.
Additional tests may be needed to establish the stage of the cancer and determine whether it has spread to other parts of the body. Doctors may also test the cancer cells for specific genetic or molecular changes because these results can influence treatment choices.
Treatment for Lung Cancer
Treatment depends on several factors, including the type of lung cancer, its stage, whether it has spread, specific changes in the cancer cells and the person’s overall health.
For cancer that is detected at an early stage and remains confined to a small area, surgery may be recommended to remove the tumour or the affected part of the lung.
Radiotherapy uses high-energy radiation to destroy cancer cells and may be used when surgery is not suitable or alongside other treatments.
Chemotherapy uses medicines to destroy cancer cells or prevent them from multiplying. It may be used when the cancer has spread or alongside surgery or radiotherapy.
Some patients may also be offered targeted therapies or immunotherapy, depending on the characteristics of their cancer. Targeted medicines work against particular changes that help cancer cells grow, while immunotherapy helps the immune system recognise and attack cancer cells.
Living With Lung Cancer
Living with lung cancer can affect a person’s physical health, emotions, work and everyday activities. Treatment can also cause side effects such as tiredness, nausea, reduced appetite and weakness.
People living with lung cancer may benefit from:
* Following their treatment plan and attending medical appointments
* Eating a balanced diet where possible
* Staying physically active within their abilities
* Getting enough rest
* Stopping smoking if they smoke
* Seeking emotional and psychological support
* Talking to family, friends or cancer-support organisations
* Informing their healthcare team about new or worsening symptoms
Supportive or palliative care can also help manage symptoms and improve quality of life, particularly for people with advanced cancer.
Prevention of Lung Cancer
Not every case of lung cancer can be prevented, but several measures can reduce the risk.
Avoiding smoking is the most important step. People who smoke can significantly reduce their risk by quitting. Avoiding exposure to second-hand smoke is also important.
People who work around asbestos, certain chemicals or other potentially harmful substances should follow workplace safety regulations and use appropriate protective equipment.
Reducing exposure to air pollution where possible and maintaining a healthy lifestyle may also contribute to overall health.
Outlook
The outlook for someone with lung cancer varies considerably. It depends largely on the type of cancer, its stage when diagnosed, the person’s general health and how well the cancer responds to treatment.
Lung cancer is often diagnosed after it has already begun to spread, partly because early-stage disease may cause few or no noticeable symptoms. Early diagnosis can improve treatment options and outcomes.
Anyone experiencing persistent symptoms such as a long-lasting cough, coughing up blood, unexplained weight loss or ongoing breathlessness should speak with a healthcare professional rather than attempting to diagnose the cause themselves.
