CO₂‑Gated End-Tidal Breathomics Maps Gastrointestinal Malignant Risk

By integrating topological data analysis, multistage risk modeling, chemical structure enrichment and single-cell transcriptomic mapping, we constructed a visualization framework for gastrointestinal malignancy risk. This framework revealed a gradient of volatile metabolic remodeling from early gastrointestinal abnormalities to malignant states and nominated propanal, butyric acid and 1-butanol as representative VOC markers with potential mechanistic relevance.

The multistage risk model achieved stable disease stratification performance (AUC = 0.78–0.94), and a proof-of-concept pre-endoscopic triage simulation estimated that the average waiting time for malignant cases could be reduced by 20%. Overall, this study establishes an iEBS-based breath VOC profiling approach for phase-controlled end-tidal collection, reproducible quantification and interpretable visualization of alveolar-derived breath signals, providing an analytical framework for the noninvasive assessment of gastrointestinal diseases.