Frailty in hepatobiliary and pancreatic (HBP) surgery: a narrative review toward an HBP-specific, implementation-oriented framework.

Background and Objective: Frailty is increasingly recognized as a predictor of adverse perioperative outcomes in hepatobiliary and pancreatic (HBP) surgery. However, vulnerability in HBP practice is often shaped by disease- and procedure-specific stressors, including cholestasis, recurrent infection, tumor-related inflammation, hepatic dysfunction, and extensive resection. Consequently, commonly used frailty tools may not adequately stratify perioperative risk or guide optimization. This narrative review critically synthesizes current evidence and proposes an implementation-oriented, HBP-specific framework, HBP onco-frailty, to support perioperative assessment and future validation. Methods: We conducted a targeted narrative review of publications from January 2010 through December 2025 using PubMed, Embase, and Google Scholar, supplemented by hand-searching of reference lists and relevant society or consensus guidance where applicable. After relevance screening and full-text review, 232 studies were retained for the final narrative synthesis. Evidence was synthesized across four domains of HBP onco-frailty: sarcopenia, malnutrition, impaired physical function, and systemic inflammation. Key Content and Findings: Widely used indices, including the modified Frailty Index (mFI) and Liver Frailty Index, are feasible and prognostically informative, but may underrepresent the inflammation- and nutrition-related biology central to many HBP malignancies. Across the literature, frailty-related measures were generally associated with postoperative complications, delayed recovery, prolonged hospitalization, and poorer tolerance of multimodal therapy, although interpretation is limited by heterogeneity in definitions, assessment timing, and outcomes. Biologically enriched approaches, including albumin-containing modified frailty indices, may improve risk discrimination in selected settings. We also describe a pragmatic strategy integrating routinely available biomarkers, including C-reactive protein, albumin, the C-reactive protein-to-albumin ratio, and the Geriatric Nutritional Risk Index, with performance-based measures to support risk stratification for endpoints including postoperative complications, delayed recovery, length of stay, readmission, and tolerance of multimodal oncologic therapy. This framework is intended not as a deterministic label, but as a scaffold linking assessment to targeted optimization, including nutrition support, prehabilitation, infection control, and treatment-timing decisions. Conclusions: HBP onco-frailty provides a clinically grounded framework that incorporates HBP-specific stress biology and shifts frailty assessment toward intervention guidance. However, the evidence remains heterogeneous, and no standardized HBP-specific definition has been established. Priorities include standardized definitions, prospective multicenter validation, and implementation studies within perioperative pathways.