OA06-LBA01.6. Phenotype-Based Framework for Decision-Making in Large Paraesophageal Hernia: Early Clinical Application and Outcome Interpretation

Abstract Topic Benign Disease: Gastro-Esophageal Reflux and Hiatal Hernia Background Large paraesophageal hernias are clinically heterogeneous, yet operative strategies and outcome measures are often applied uniformly. This creates a disconnect between patient presentation, operative intent, and outcome interpretation. A phenotype-based framework may provide a structured approach linking clinical presentation to operative priorities and clinically meaningful outcomes. Methods A structured conceptual framework was developed through focused synthesis of contemporary literature and iterative clinical reasoning. A minimal dataset was defined across four domains: anatomical configuration, dominant clinical presentation, oesophageal physiology, and patient risk profile. Patients were grouped into dominant clinical phenotypes, and for each phenotype, primary operative objectives and relevant outcome domains were defined. A phenotype–decision matrix was constructed linking preoperative characterisation with operative strategy and outcome interpretation. The framework was prospectively applied to a consecutive illustrative cohort of patients undergoing repair of large paraesophageal hernia. All patients underwent multidomain assessment, including anatomical, reflux, mechanical, respiratory, and global outcome measures. Feasibility of phenotype assignment and alignment between phenotype-specific operative priorities and outcome interpretation were evaluated. Results Four dominant clinical phenotypes were identified: mechanical, reflux-dominant, respiratory, and risk-constrained. All patients in the illustrative cohort (n=15) were assignable to a dominant phenotype, demonstrating feasibility of classification. Operative strategies showed alignment with phenotype-specific priorities, with consistent selection of key technical components according to the dominant clinical driver. Across the cohort, outcomes were assessed in all domains, with differential relevance observed according to phenotype. In patients with a respiratory phenotype, repair was associated with improvement in respiratory symptoms and or objective respiratory function where available. Symptom control predominated in reflux-dominant cases. Anatomical recurrence showed variable clinical relevance across phenotypes, with differing relationships to symptom outcomes. These findings support context-dependent interpretation of outcomes and highlight limitations of uniform endpoint reporting across heterogeneous patient groups. Conclusion This phenotype-based framework provides a structured model linking patient presentation, operative strategy, and outcome interpretation in large paraesophageal hernia. Early clinical application demonstrates feasibility and internal consistency, and shows that outcomes measured uniformly acquire different relevance according to phenotype. The framework supports more transparent decision-making and provides a foundation for expert consensus and prospective validation through Delphi methodology and collaborative studies.