Pathological and Perioperative Outcomes of Conversion Hepatectomy After Contemporary Combination Downstaging for Initially Unresectable Hepatocellular Carcinoma: A Systematic Review.

Background and Objectives: Conversion therapy has expanded treatment options for patients with initially unresectable hepatocellular carcinoma (HCC), but the surgical literature remains focused more often on radiologic response than on the pathological, perioperative, and postoperative outcomes of patients who actually proceed to hepatectomy. This focused systematic review aimed to synthesize the available evidence on conversion hepatectomy after contemporary combination downstaging for initially unresectable HCC. Materials and Methods: A structured PubMed/MEDLINE search with backward reference-list screening was performed and last updated on 3 February 2026. The full Boolean strategy, field tags, and eligibility framework are now reported explicitly. Because the literature was observational and clinically heterogeneous, findings were synthesized narratively and complemented by structured assessments of reporting completeness, potential cohort overlap, and study-level bias. Results: Fourteen studies were included, nearly all retrospective and predominantly from East Asia. Treatment platforms clustered into systemic doublets, systemic plus HAIC strategies, and broader locoregional-systemic triplet or multimodal approaches. Across studies reporting pathological response, pathological complete response ranged from 28.0% to 50.0%, while R0 resection ranged from 85.7% to 100%, where stated. Postoperative morbidity ranged from 14.3% to 71.4%, and major complication rates from 9.5% to 16.9%; however, extent of resection, liver reserve, post-hepatectomy liver failure, transfusion, and perioperative mortality were not uniformly reported. Most studies carried moderate-to-high overall concerns for bias because of response-based surgical selection, heterogeneous denominators, incomplete perioperative reporting, and possible partial overlap among some cohorts. Conclusions: The available literature suggests that conversion hepatectomy can be feasible and oncologically meaningful in carefully selected patients treated in experienced centers, but current evidence remains hypothesis-generating rather than practice-standardizing because it is observational, heterogeneous, and incompletely reported.