Understanding the variation of modern endoscopic ultrasound use in patients with oesophageal cancer (VALUE): protocol for a multi-methods study.

Objectives: Over 9000 patients are diagnosed with oesophageal cancer annually in the United Kingdom (UK). Decision-making about treatment options is influenced by radiological staging, which may include computed tomography (CT), positron emission tomography (PET), and endoscopic ultrasound (EUS). The use of EUS varies considerably around the UK and, since the introduction of PET-CT, the added value of EUS has been questioned. The VALUE study aims to understand this variation and determine how often and why EUS changes treatment decisions. VALUE will also evaluate patient and clinician experiences and opinions of EUS. Methods: This is a prospective, observational study investigating EUS in oesophageal cancer staging. Patients will be recruited at up to eleven sites in the UK, where they will be consented (if eligible) and registered onto iMedidata RAVE. Clinical and demographic data, TNM staging, pre and post EUS treatment decisions, and complications will be collected. We will attempt to sample patients from ethnic minority backgrounds in the study population, as they are underrepresented in research. Up to 30 patients and 30 clinicians will be interviewed to evaluate the use of EUS and experiences of both patient and clinician. The primary endpoint is the proportion of cases that EUS changes treatment decisions. Secondary endpoints include identification of factors that clinicians' and patients consider when deciding if EUS should be used, the time from diagnosis to treatment decision before and after EUS, and the reasons why EUS changed management. The study has been registered on Clinicaltrials.gov: NCT06440174. The trial is open to recruitment. Results: In total, 180 patients with potentially curable oesophageal cancer who are suitable for EUS will participate. Recruitment is currently planned until September 2025 and study results will be reported after June 2026. Conclusion: The VALUE study will enable a better understanding of how and why EUS is used in oesophageal cancer. This research will identify important factors that clinicians and patients consider when deciding EUS use and determine the frequency that EUS changes treatment decisions in the modern staging pathway. Advances in knowledge: The VALUE study is a prospective, multi-centre observational study investigating the use of EUS in the modern era of oesophageal cancer staging. The study aims to determine how often and why EUS changes treatment decisions. A qualitative component will explore both clinician and patient attitudes towards EUS.