Lung cancer

Lung cancer is defined as a cancer that starts with the development of abnormal cells in the lungs which multiply in an uncontrolled way (WHO, 2023). The condition can be primary (developing first in the lungs) or secondary, when spread from a cancer at another site has resulted in secondary deposits in the lungs. Primary lung cancer is the third most common cancer in the UK (Cancer Research UK, 2022), and statistics suggest that 1 in 13 males and 1 in 15 females will be diagnosed with lung cancer in their lifetime, with the highest incidence rates in people aged 85 to 89 (Tidy, 2022). The disease is regarded as preventable, and yet it remains a leading cause of cancer-related deaths around the world, responsible for high rates of morbidity and mortality. 

In its early stages, symptoms may be minimal, but once they do become evident, they may mimic symptoms of several other conditions making diagnosis more challenging. A third of patients diagnosed with lung cancer have attended their GP with symptoms attributable to the disease three or more times before diagnosis, which, unfortunately, leads to most lung cancers being diagnosed at an advanced stage (Bradley et al, 2018).  The most common symptoms are (Siddiqui et al, 2023; NICE, 2021):

• Cough: Patients may present with a persistent cough that has lasted for 3 weeks or more, and this symptom is present in 50–75% of patients with lung cancer
• Haemoptysis: Present in 15–30% of patients
• Chest pain: Present in 20–40% of patients
• Dyspnoea: May be present in 25–40% at the time of diagnosis
• Loss of appetite
• Fatigue
• Hoarseness: When there is laryngeal nerve involvement.

Other symptoms warranting urgent investigation are shown in Table

The underlying processes leading to the development of the disease are very complex and despite intensive research, remain poorly understood. The major cause of lung cancer is tobacco smoking, which is estimated to be responsible for 80–85% of cases worldwide (Hung et al, 2020). The most common specific location for lung cancers to develop in the UK is the upper lobe of the bronchus or lung (Tidy, 2022). The risk is highest in males who smoke and for those exposed to passive smoking, and it is estimated that their risk increases by approximately 20–30% (Siddiqui et al, 2023). In addition to smoking there are many other factors thought to be associated with the development of lung cancer, including indoor air pollution, cooking fumes in poorly ventilated homes, and outdoor air pollution. Asbestos exposure, particularly occupational exposure, increases the risk for lung cancer in a dose-dependent manner but varies according to

Initial assessment needs a thorough history of symptoms, past medical history, family history and whether the patient is a current or ex-smoker. During the history the patient may give some symptoms suggestive of metastases (Table 2). 

Any patient suspected of

Non-small cell cancers (NSCLCs) (Ananth, 2025)

• Stages I–III: Surgery is the recommended first line and may be a lobectomy or pneumonectomy. If surgery is unsuitable or declined by the patient, stereotactic ablative radiotherapy may be offered. This delivers highly focused intense doses of radiation but limits exposure and damage to healthy tissues.
• Stage IV: All patients who are well enough should be offered chemotherapy. Stage IV disease is considered incurable, and therapy is aimed at improving survival and alleviating symptoms; however, only 10% to 30% of patients respond to chemotherapy, and only 1% to 3% survive 5 years after diagnosis (Siddiqui et al, 2023). 

Small cell cancers

Cancers of this type are very sensitive to chemotherapy but unfortunately have a very high recurrence rate (Siddiqui et al, 2023). Treatment depends on the stage of the disease and may be chemotherapy and radiotherapy for those with early-stage disease. In more advanced

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