In the UK 13000 people are diagnosed with oesophageal and gastric cancer annually. Despite improvements in surgical and oncological treatment of oesophageal and gastric cancer 5-year survival remains poor at 10-30%. At the present time only one third of patients with oesophago-gastric cancer are managed on a curative treatment pathway due to the fact that most cancers are at an advanced stage by the time of diagnosis. There is a clear need for a non-invasive test to diagnose oesophago-gastric cancer at the earliest possible stage.
Previous studies have highlighted potential volatile organic compound (VOC) biomarkers present in the exhaled breath of patients with oesophago-gastric cancer which could be used in future to develop a non-invasive diagnostic test. The primary aim of this thesis was to address the barriers to scaling exhaled breath testing for VOCs into clinical practice.
A high throughput exhaled breath collection system has been developed to enable large scale multi-centre studies to be performed. The impact of potential confounding factors on breath testing for oesophago-gastric cancer have been assessed, potential new biomarkers have been identified and a quality control system to be used in future studies has been developed with the ultimate aim of validating a breath test for oesophago-gastric cancer in clinical practice.