Clinical factors associated with surgical resection rate and survival prognosis after conversion therapy with HAIC combined with targeted and immunotherapy for unresectable hepatocellular carcinoma.

e16211 Background: Hepatic artery infusion chemotherapy (HAIC) combined with targeted and immunotherapy is currently one of the main treatment strategies for unresectable hepatocellular carcinoma (uHCC). Although various centers worldwide are conducting related clinical trials, the efficacy of conversion therapy and the factors influencing long-term survival remain under investigation. This study aims to identify potential factors affecting the surgical resection rate and overall survival following conversion therapy, based on clinical data from a single-center study in Asia. Methods: The study has been approved by the Ruijin Hospital Ethic Committee of Shanghai Jiaotong University of Medicine (RJ2023-416), and the requirement for informed consent was waived due to the retrospective nature of the study. The data collected were retrospectively controlled and classified. From 2020 to 2024, all patients diagnosed with uHCC due to portal vein tumor thrombus at Ruijin Hospital, Department of Hepatobiliary Surgery, and who received HAIC combined with targeted and immunotherapy were assessed according to inclusion and exclusion criteria, and ultimately enrolled in this retrospective study. Clinical features were retrospectively analyzed as were the long-term survival outcomes. Results: A total of 65 patients were ultimately included in this retrospective study. Among them, 19 (29.2%) patients achieved partial tumor response following conversion therapy and successfully underwent curative resection. A reduction of more than 50% in Alpha-Fetoprotein (AFP) or a reduction of more than 75% in Protein induced by vitamin K absence/antagonist-Ⅱ (PIVKA-Ⅱ) after the first conversion therapy were significantly correlated with the surgical resection rate. According to the mRECIST criteria, a reduction in the maximum diameter of residual tumors of less than 11.9% at the time of curative surgery was identified as a significant risk factor for poor prognosis (503.6 vs 581.5 days, p < 0.05). Conclusions: HAIC combined with targeted and immunotherapy is an effective conversion therapy for uHCC. After the first conversion therapy, patients with a more than 50% reduction in AFP or a 75% reduction in PIVKA-Ⅱ showed a significantly higher surgical resection rate. Among those undergoing curative surgery, patients with a reduction in tumor activity diameter exceeding 88.1% had significantly improved prognosis compared to those with a smaller decrease.