Lung cancer is one of the most common and serious cancers in the UK, with around 48,000 people diagnosed each year. It is the second most common cause of cancer death in the UK, largely because symptoms are often dismissed or attributed to other causes — particularly smoking-related conditions.
The challenge with lung cancer is that symptoms can be subtle in the early stages and are often mistaken for a persistent chest infection, asthma, or the effects of smoking. Knowing what to look for — and acting promptly — can significantly improve outcomes.
Important: This article is for awareness purposes only and does not replace professional medical advice. If you are concerned about any symptom, contact your GP or call NHS 111.
A persistent cough lasting 3 weeks or more
See GP promptlyA cough that does not go away after 3 weeks is one of the most important warning signs of lung cancer. This is particularly significant if you are a smoker or ex-smoker, but lung cancer can affect non-smokers too. If you have a new cough, or your existing cough has changed in character, see your GP.
Coughing up blood
See GP promptlyCoughing up blood — even a small amount — should always be investigated urgently. It may appear as blood-streaked phlegm or bright red blood. This symptom should never be ignored or attributed to a minor cause without a medical assessment.
Persistent breathlessness
Feeling breathless during activities that would not normally cause you to be short of breath, or breathlessness that is getting progressively worse, can be a sign of lung cancer. This may be caused by the tumour blocking an airway or by fluid building up around the lungs.
Chest pain or shoulder pain
Persistent chest pain, particularly pain that is worse when breathing deeply, coughing or laughing, can be a symptom of lung cancer. Pain in the shoulder or arm may also occur if the tumour is pressing on certain nerves. Any unexplained, persistent chest or shoulder pain should be assessed by a GP.
Unexplained weight loss and fatigue
Losing weight without trying, combined with persistent tiredness that does not improve with rest, are general cancer warning signs that are also associated with lung cancer. These symptoms often appear alongside other lung-specific symptoms but can sometimes be the first signs noticed.
Hoarseness or voice changes
A persistent hoarse voice or a noticeable change in your voice that lasts more than 3 weeks can indicate lung cancer, particularly if the tumour is pressing on the nerve that controls the voice box. This symptom is often overlooked but should be investigated if it persists.
When to act
NHS Targeted Lung Health Checks
The NHS is rolling out Targeted Lung Health Checks for people aged 55 to 74 who are current or former smokers. These checks include a low-dose CT scan that can detect lung cancer at an early, more treatable stage — before symptoms appear.
If you are in the eligible age group and have a history of smoking, ask your GP whether you are eligible for a lung health check in your area. If you have symptoms, do not wait for a screening invitation — contact your GP directly.
Medically reviewed: · Information aligned with NHS and NICE guidance.