Using circulating tumour DNA to diagnose pleural mesothelioma

As a tumour or cancer grows, its cells die and are replaced by new ones. The dead cells get broken down and their contents, including their DNA, are released into our bodily fluids such as our blood, urine or cerebrospinal fluid. This is called circulating tumour DNA (ctDNA).

Different people will have different quantities of ctDNA in their body, depending on the type of tumour, its location, and the stage their cancer is at. Testing for ctDNA could help healthcare staff:

• detect and diagnose the presence of tumours
• adjust treatment to specific tumour types
• monitor treatment
• monitor patients who are in remission from cancer

Project aims

We want to find out if we can extract ctDNA from pleural fluid and use it to potentially diagnose a type of cancer called mesothelioma. Mesothelioma is a type of cancer that develops in the lining that covers some of the body’s organs. People who have been exposed to asbestos may develop it and it mainly affects the lining of the lungs.

Pleural fluid helps the layers of tissue covering the lungs and the interior wall of the chest glide smoothly past each other while we breathe. We want to use historic pleural fluid from patients diagnosed with mesothelioma and compare it to fluid from patients diagnosed with another type of lung cancer. This will help us understand whether testing for ctDNA could help with diagnostics during routine clinical care.

What we hope to achieve

We hope to improve the diagnostic process for people with suspected mesothelioma by

• speeding the process up
• potentially avoiding the need for additional invasive procedures
• characterising their disease type to inform prognosis and help decision-making

This work is being led by Dr Geraldine Lynch with supervision from Dr Anna Bibby and Professor Nick Maskell.