RE-TEST THEM: A Human Factors Pilot Study to De-Risk the Adoption of Breath-Based Therapeutic Monitoring in Oesophagogastric Cancer

Abstract

Oesophagogastric (OG) cancer remains a cancer of unmet need, with poor survival driven by delayed diagnosis, aggressive tumour biology, and inherent treatment resistance. Analysis of exhaled breath volatile organic compounds (VOCs) offers a promising, non-invasive approach to characterising tumour biology and identifying potential therapeutic vulnerabilities. Within the RE-TEST THEM (bREath TESTing for THErapeutic Monitoring) project, a breath test has been developed to identify patients who may benefit from experimental therapies such as PARP inhibitors. However, its clinical value depends on its integration into clinical decision-making rather than analytical performance alone.This exploratory pilot study applied a human factors approach to examine the usability, acceptability, and decision-making implications of the breath test. Semi-structured interviews were conducted with eleven patients, alongside a vignette-based decision-making exercise with four consultant oncologists using four realistic scenarios covering curative and palliative pathways.Findings demonstrated a clear division in perceived utility between clinical settings. In the curative pathway, clinicians were highly cautious, requiring strong evidence and clear thresholds before allowing test results to influence potentially curative care. For palliative patients, the test was viewed as more acceptable for supporting nuanced decisions about treatment continuation or cessation. Importantly, from a practical perspective, breath testing was seen as easily feasible with limited patient burden, however, the key challenge of integrating results into complex clinical decision-making repeatedly highlighted. These findings demonstrate the value of early human factors evaluation in de-risking experimental diagnostics and guiding their responsible adoption in cancer care.

Keywords: Clinical Decision-making, Workflow Integration, Breath-based Diagnostics, Precision Oncology, Human Factors

DOI: 10.54941/ahfe1007487