Around 46,000 people are newly diagnosed with lung cancer every year in Britain, according to Cancer Research UK.
And although 89% of cases are preventable, lung cancer accounts for roughly 36,000 deaths a year.
The lungs are part of a complex apparatus, expanding and relaxing thousands of times each day to bring in oxygen and expel carbon dioxide.
There are many types of lung disease including pneumonia, asthma and tuberculosis and lung cancer.
Smoking is the main avoidable risk factor for lung cancer, linked to an estimated 86% of cases in the UK.
An estimated 89% of lung cancers in the UK are linked to lifestyle factors such as occupational exposures (13%), and ionising radiation (5%).
But what are the early warning signs of lung cancer? Here are seven things that could indicate you are suffering from the life-threatening disease:
1. Chronic cough
A cough that doesn't go away after two or three weeks or a long-standing cough that gets worse.
This is an important early symptom that tells you something is wrong with your respiratory system
2. Persistent chest infections
Chest infections are common, especially after a cold or flu during autumn and winter. But if you just can't get rid of it, it could be a sign of something more serious.
3. Wheezing
Noisy breathing or wheezing is a sign that something unusual is blocking your lungs' airways or making them too narrow.
Wheezing from one side of your chest is a common sign that you have a tumour.
4. Coughing up blood
If you are coughing up blood, it may be coming from your lungs or upper respiratory tract. Wherever it's coming from, it signals a health problem.
5. Pain when breathing
Pain while breathing could be an early warning sign of cancer. Laboured or difficult breathing – the feeling that it is hard to breathe in out – is also a red flag.
6. Tiredness of lack of energy
Everyone gets tired and run down from time to time, but if you constantly feel exhausted you should contact your doctor.
Tiredness of lack of energy could be a sign of lung disease, but it's also a symptom of type-2 diabetes.
7. Loss of appetite/unexplained weight loss
If you're normally a big eater, but you've suddenly gone off your food this could be a sign of something more serious.
Losing weight suddenly for no reason could also be a symptom.
