Conversion hepatectomy for unresectable hepatocellular carcinoma: Principles of patient selection and surgical decision-making.

Modern systemic regimens have increased objective response in unresectable hepatocellular carcinoma (HCC), producing a small but clinically important population in whom curative-intent local treatment can be considered. And yet response is not synonymous with resectability, and resectability is not synonymous with an indication for hepatectomy. This review begins at the point of making a post-response decision rather than ranking conversion regimens or proposing a general framework for longitudinal treatment sequencing. We separate technical, liver-functional, and oncological unresectability and propose a 5D framework-Disease extent and biology, Depth and durability of response, Definitive disease clearance, Durable liver reserve, and Decision timing-to distinguish patients who merely respond from those for whom resection is both feasible and rational. Retrospective series support feasibility and occasionally durable disease control in selected patients. The TALENTOP phase 3 trial now provides the first randomized comparative signal favoring resection in a narrowly defined post-induction population already judged suitable for R0 resection; however, overall survival remains immature, and the trial has not demonstrated a general causal survival benefit for all responders. The next phase of research should therefore validate reproducible decision rules, prespecify resectability assessments, and anchor analyses to the time surgical eligibility is achieved. Conversion hepatectomy should be understood not as a strict requirement after tumor shrinkage but as an irreversible switch in treatment justified by concordant tumor biology, depth and durability of response, complete disease clearance, hepatic safety, and superiority over available alternatives.