The purpose of this study is to prospectively asses established biomarkers in the diagnosis and prognosis of patients and will include assessment of a number of biomarkers, genomics and proteomics.

A prospective observation study examining the clinical utility of novel pleural fluid, biopsy and serum biomarkers for the investigation of pleural effusions (INVEST). The INVEST study will collect blood, pleural fluid and tissue samples from donors, allowing the opportunity to apply several novel blood and pleural fluid tests with interpretation of results in the context of clinical data and diagnostic suspicion. Through the prospective application of multiple tests, we aim to validate the sensitivity and specificity of existing biomarkers and identify novel markers that aid in the diagnostic pathway of pleural diseases. Because samples and data will be stored for future use, many other different tests, methods and techniques may be used in the future to provide information that we cannot foresee.

Inclusion Criteria:

• Undiagnosed pleural effusion or pleural thickening requiring investigation by one of the following:

  • Pleural aspiration
  • Pleural biopsies from medical thoracoscopy or
  • Ultrasound guided biopsies as part of the clinical plan

• Suspected lung cancer undergoing bronchoscopy and biopsies.

Exclusion Criteria:

• Inability to give written informed consent
• Inability to obtain pleural fluid, blood, endobronchial or pleural biopsies as applicable

This is a prospective single centre study looking to recruit 300 participants to help prospectively evaluate the sensitivity and specificity of known diagnostic biomarkers and discover novel biomarkers in pleural diseases. Patients aged 18 or over, requiring investigation and/or management of any undiagnosed pleural effusion or pleural thickening will be approached about the study within Oxford University Hospital NHS Foundation Trust.