Lung cancer

• In the UK, fewer men are smoking and deaths from lung cancer in men have decreased.
• The number of women who smoke has increased, along with an increase in deaths from lung cancer.
• Emergency presentation is the most common route to diagnosing lung cancer.
• The TNM (tumour, node, metastasis) system is one that is used to stage lung cancer.

When many patients with lung cancer present to healthcare providers, they are in an advanced stage of their disease (Preston and Kelly, 2017). Living with any respiratory condition can have a significant impact on a person's health and wellbeing; it can also impact on families, as well as the nation's economy and health and social services.

The respiratory system is a major bodily system, primarily for the exchange of gases as the person inhales and exhales—and any change in this important activity can result in serious, life-changing events. Breathlessness and fatigue can mean that the patient is unable to carry out some or all of the activities of daily living (ADLs), such as eating, bathing, getting dressed, toileting, transferring and continence. 

The respiratory tract

The key function of the respiratory system is to ensure that the body takes in enough oxygen from the atmosphere, while at the same time disposing

An individual's risk of developing cancer will depend on a number of modifiable and non-modifiable risk factors. Modifiable risk factors, such as smoking, obesity and alcohol consumption, can be changed. Where as non-modifiable risk factors, such as a person's age or genetics, cannot be altered (Table 1). 

Smoking, the main avoidable risk factor, has been linked to approximately 90% of lung cancer cases (British Lung Foundation, 2017). Most cases of lung cancer in the UK, 89%, have been linked to lifestyle factors, as well as specific occupational exposures (13%) and ionising radiation (5%). 

Types of lung cancer

There are different types of primary lung cancer:

1. non-small cell lung cancer (NSCLC)
2. small cell lung cancer (SCLC)

The type of lung cancer the patient has provides information of the type of cell that the cancer started in (Table 2). This is important, as knowing this helps to ensure the patient receives the most appropriate type of treatment. 

Other cancers that affect the lungs are:

• mesothelioma (affects the tissue that surrounds the lungs)
• carcinoids (these tumours are uncommon, tending to grow

Many patients with lung cancer present in an advanced stage of their condition as patients tend to not have any symptoms until the tumour becomes quite large. The cancer may only be discovered when the patient is having an X-ray or scan for a different reason (an incidental finding).

There are a number of signs and symptoms the patient may experience and these vary from patient to patient. 

Box 1. Signs and symptoms that may be indicative of lung cancer

• cough longer than 3 weeks or an altered cough (wheezing and stridor)
• increasing dyspnoea
• loss of weight for no obvious reason
• unresolving chest or shoulder pain
• haemoptysis
• a hoarse voice
• bone pain
• finger clubbing
• malaise/fatigue
• dysphagia
• headache
• nausea and vomiting (Preston and Kelly, 2017; Cancer Research UK, 2018; Wheeldon, 2018; National Institute for Health and Care Excellence, 2019)

Other presentations include recurrent or slowly resolving pneumonia, anorexia and supraclavicular or

Emergency presentation is the most common route to diagnosing lung cancer (Newsom-Davis, 2017). This route to diagnosis is a strong negative predictor of survival. If there is strong suspicion that a patient may have lung cancer, referral to a rapid access clinic or urgent cancer clinic is required.

A detailed medical history and physical examination is required, which will help to guide the tests and investigations that may be necessary. Often, lung cancer shows up in chest X-ray findings. A definitive diagnosis is usually confirmed through histology or cytology and this can be achieved by a variety of methods.