Family history of lung cancer: what it means for your risk

Cancer Research UK says your risk of lung cancer is higher if you have a close relative, such as a parent or sibling, who has had lung cancer, and that researchers are looking at how genes could affect risk. The NHS also lists a close relative having had lung cancer among the things that may make you more likely to get it.

The sources used here do not give a figure for the size of the increase. It is also worth recognising why family history and lung cancer so often go together. Families can share environments, including a home with smoke or radon, and sometimes shared smoking habits, as well as genes. A family history is a reason to take the changeable risks seriously, not a reason to assume the outcome.

Cancer Research UK says smoking tobacco is the biggest cause of lung cancer in the UK, and that more than 60 out of 100 lung cancers are caused by smoking. This includes breathing in other people's cigarette smoke. Even light or occasional smoking increases the risk, and the risk goes up the longer and the more you smoke.

The NHS lists smoking, and having often breathed in other people's smoke over a long period, first among the things that may make lung cancer more likely. Cancer Research UK says stopping smoking is the best thing you can do for your health, and for someone with a family history that is the most effective single step.

The NHS says it is not always known what causes lung cancer, but that it can be caused by lifestyle, genetic changes and environmental factors, and that certain health conditions can make it more likely.

• Chronic obstructive pulmonary disease (COPD).

• Working, or having worked, in the building industry and breathing in asbestos fibres over a long period. Cancer Research UK also lists silica and diesel exhaust.

• Breathing in air pollution over a long period. Cancer Research UK says outdoor air pollution causes 8% of UK lung cancer cases.

• Breathing in radon over a long period, a natural gas sometimes found at high levels inside buildings in some areas of the UK.

• High-dose beta-carotene supplements in people who smoke or used to, according to Cancer Research UK, which advises speaking to a doctor or pharmacist first.

The NHS says you may not notice any symptoms in the early stages. Common symptoms include a cough that is not going away, shortness of breath, coughing up blood, chest or shoulder pain, often having chest infections or one that does not get better, losing weight without trying, loss of appetite and feeling tired all the time. Less common ones include swelling of the face or neck, difficulty swallowing, a hoarse voice that does not go away and changes in how the fingers look (clubbing).

Many of these are common and can be caused by other conditions, so having them does not definitely mean lung cancer. The NHS stresses it is still important to get checked.

See a GP if you have had a cough for longer than 3 weeks or have any other symptoms of lung cancer. Ask for an urgent GP appointment or get help from NHS 111 if you have coughed up blood or noticed blood on a tissue. Call 999 or go to A&E if you are struggling to breathe, choking or gasping and unable to speak, or have pain in your chest or upper back.

The NHS says at the appointment the doctor will ask about your symptoms, general health, medical history and whether anyone in your family has had lung cancer, and may listen to your chest, arrange a blood test or a chest X-ray. You may get an urgent referral to a specialist if the GP thinks symptoms could be cancer, which does not definitely mean you have it.

Make sure you mention a family history of lung cancer, and any exposure to asbestos or other hazards at work.

The NHS says to quit smoking, stay active and exercise regularly, and eat a healthy diet including at least 5 portions of fruit and vegetables a day. If you smoke and live in a high radon area, Cancer Research UK says it is even more important to stop smoking because the risk from radon increases if you smoke.

Stop smoking support is available through the NHS. The sources used here do not describe lung screening for people whose only risk factor is a relative with lung cancer, so ask your GP what is available for you.