What is lung cancer?

Lung cancer is often thought of as the most lethal forms of cancer, and it is the leading cause of cancer-related deaths in the western world.

There are two types of lung cancer; small cell lung cancer and non-small cell lung cancer. Non-small cell lung cancer is more common and its subtypes are; squamous cell carcinoma, adenocarcinoma, and large cell carcinoma.

What are the symptoms of lung cancer?

There are many lung cancer symptoms, however, the most common ones are:

• Persistent cough
• Coughing with blood or blood-streaked phlegm
• Chest pain that worsens when breathing deeply, coughing, or laughing
• Tiredness or exhaustion
• Hoarseness  
• Weight loss

What causes lung cancer?

The main cause of lung cancer is smoking. However, as with other types of cancer, the cause may be multifaceted and many could cause it to develop. The main risk factors are: 

• Family history of lung cancer
• Environmental factors
• First-hand and second-hand smoking

A risk factor is not necessarily a cause. It may happen that some people who have all the risk factors are never affected by lung cancer but others who have no risk factors develop it.

What are the different types of lung cancer?

Small cell lung cancer (SCLC)

Around 15 to 20 per cent of diagnosed lung cancer in the UK are SCLC. They start in the neuroendocrine cells of the lung and they tend to spread quite early on. Smoking is usually the cause of SCLC.  

Non small cell lung cancer (NSCLC)

Between 80 to 85 per cent of UK lung cancers are non small cell lung cancer (NSCLC). NSCLC comes in three types. They are:

• Adenocarcinoma

Adenocarcinoma is the most common type of NSCLC. It begins in the mucus-creating gland cells in the lining of your airways. 

• Squamous cell carcinoma

Squamous cell carcinoma develops in the flat cells that cover the airway surfaces, and grows close to the lung centre.

• Large cell carcinoma 

Other types of lung cancer

• Lung lymphoma
• Salivary gland type tumours
• Lung sarcoma
• Pancoast tumours
• Mesothelioma
• Secondary lung cancer

What is metastatic lung cancer?

Metastatic lung cancer is lung cancer that has started to spread to other parts of the body. Cancer cells can separate from a tumour, and travel through the blood or lymph system to other areas of the body. It can also be referred to as advanced lung cancer and usually cannot be cured.  

The nature of metastatic cancer means that it may cause fluid that contains cancer cells to collect around the lung. It's known as pleural effusion, or fluid on the lung. 

Lung cancer can spread to:

• Other parts of the lungs
• the adrenal glands, which are just above the kidneys
• the liver
• the bones
• the brain
• lymph nodes that are close by

How is lung cancer diagnosed?

The primary test used to diagnose is a chest X-ray, where most lung tumours appear as a white-grey looking mass. Despite this, chest X-rays can't give a definitive diagnosis. This is due to the fact that the mass may also represent other conditions such as a lung abscess. Further tests can be arranged to investigate if you have lung cancer. 

Other methods of lung cancer diagnosis are:

• CT scan
• PET-CT scan (Position emission tomography-computerised tomography)
• Biopsy

There are various types of biopsies to diagnose lung cancer. These are:

• Bronchoscopy
• Thoracoscopy
• Mediastinoscopy
• Percutaneous needle biopsy

Once tests have been completed, doctors should be able to determine what stage your cancer is.

How is lung cancer treated?

There are different treatments, some involve surgery and some don’t.

There are benefits to using a combination of different treatments, such as surgical, chemotherapeutic, and radiotherapeutic treatments. Quite often treatment will involve chemotherapy and radiotherapy but avoid surgery.  

Early diagnosis is important for a better prognosis, when the cancer is only a few centimetres big. In these cases, the tumour can be removed and survival and prognosis significantly improve.

How does lung cancer progress over time? Can it be cured?

Successful remission for lung cancer depends on how early it's found and treated, alongside any other health issues you may be dealing with. Even after remission (no signs of the cancer) of years or decades, lung cancer can come back. This has led to the general consensus that lung cancer will never be truly cured.    

How can it be prevented? 

The best way to reduce the risk is to not smoke and also avoid second hand smoke. The length of time as a smoker is a higher risk factor compared to the quantity of cigarettes smoked daily. Quitting smoking at any age can greatly reduce the risk of developing lung cancer, more so than just reducing the amount smoked.

What specialist treats lung cancer?

Pulmonologists, oncologists and thoracic surgeons all treat lung cancer in various ways. Learn more about the specialists that can treat lung cancer depending on your needs.