Current and former smokers aged 55 to 74 can get their lungs checked for free as part of a national NHS pilot programme.
More than 14,000 people in Barking and Dagenham who are eligible should receive an invitation to a lung check appointment over the next 12 months.
These are arranged by invite only and NHS North East London is urging recipients to follow the instructions in the letter and keep their appointment.
It's part of a pilot called the Targeted Lung Health Check programme, which is available in the borough for the first time.
The aim is to improve earlier diagnosis of lung cancer at a stage when it is more treatable.
Clinical director for the programme, Dr Rebecca Taylor, said: “A lung health check is a free MOT of the lungs.
"It finds out how well your lungs are working and aims to rule out any serious conditions.
"Often, early problems with the lungs do not cause any symptoms, so it is therefore important for people to attend even if they are fit and healthy."
The lung health check takes place in two stages.
First, a specially-trained healthcare professional will conduct an initial phone assessment.
Then, if a person is found to be at high risk, they will be offered a low dose computerised tomography (CT) scan of the lungs for further investigation.
The simple scans will be taking place for those who are invited in a dedicated truck at Barking Sporthouse and Gym in Mayesbrook Park.
Dr Taylor added: "Most of the time, nothing is found but if there are any problems with how your lungs are working, such as cancer, finding out early can make treatment simpler and more successful.
"The outcome of treatment for lung cancer is much better when it is diagnosed at an early stage, so we will be helping to save lives."
The Targeted Lung Health Check programme also aims to promote healthier lifestyles.
People will be offered advice about quitting smoking and encouraged to get in touch with their local services.
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