This retrospective cohort study collected data of patients with huge hepatocellular carcinoma (HCC) treated between June 1, 2018, and December 31, 2023, through the hospital information system. Patients were divided into a neoadjuvant conversion-first cohort and an upfront surgery cohort based on whether they received preoperative locoregional therapy combined with targeted and immunotherapy. The conversion-first cohort was further stratified into a conversion surgery group and a non-surgery group according to whether curative-intent hepatectomy was ultimately achieved. The upfront surgery cohort was divided into a postoperative adjuvant therapy group and a postoperative surveillance group based on whether adjuvant immunotherapy was administered after surgery. The primary objective was to analyze differences in overall survival (OS) and progression-free survival (PFS) among the four groups and to evaluate the impact of neoadjuvant conversion therapy on the safety of hepatectomy.