BITS-TO-HCC Study: HAIC+Iparomlimab/Tuvonralimab + Bevacizumab + Surgery/SBRT for BCLC-C HCC With PVTT and/or Oligometastases

This single-center, prospective, single-arm Phase II clinical trial is designed to evaluate the efficacy and safety of combining hepatic artery infusion chemotherapy (HAIC, for up to 4 cycles) with iparomlimab/tuvonralimab plus bevacizumab followed by multidisciplinary team (MDT) evaluation for surgical resection or stereotactic body radiotherapy (SBRT) in patients with Barcelona Clinic Liver Cancer (BCLC) stage C hepatocellular carcinoma (HCC) who present with portal vein tumor thrombus (PVTT) or extrahepatic oligometastatic disease. The study aims to determine whether this combination strategy can prolong progression-free survival (PFS), while also improving overall survival (OS), objective response rate (ORR), disease control rate (DCR), and local control rate (LCR), and evaluate the conversion rate to surgical resectability, as well as maintaining quality of life (QoL). In addition, the trial will systematically evaluate the safety profile and treatment-related toxicities associated with this regimen.

Inclusion Criteria: 1. Male or female patients aged between 18 and 70 years. 2. Unresectable HCC, BCLC Stage C according to the BCLC strategy-2026 update, with staging established via biopsy pathology and/or clinical diagnosis. 3. Child-Pugh class A without clinically significant hepatic decompensation; Eastern Cooperative Oncology Group (ECOG) performance status 0-1 4. Metastatic burden and local therapy eligibility * Extrahepatic oligometastatic disease defined as ≤3 involved organs with ≤5 total metastatic lesions * All intended intrahepatic and/or extrahepatic SBRT targets must satisfy protocol-specified target-coverage, liver reserve, and organ-at-risk (OAR) constraints within a composite 5-fraction plan 5. Prognosis \& measurable disease * Life expectancy ≥3 months * ≥1 measurable lesion (per RECIST 1.1): * Tumor: ≥10 mm (CT long axis) * Lymph node: ≥15 mm (CT short axis) 6. Prior therapy * Prior locoregional therapy permitted：radiofrequency ablation (RFA), TACE, or HAIC, provided that: * Documented radiographic progression or intolerance after the prior therapy * Washout ≥28 days * Treatment-related toxicities recovered to ≤Grade 1 (alopecia and peripheral neuropathy ≤Grade 2 allowed) 7. Laboratory and virologic requirements * Aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) ≤5 × upper limit of normal (ULN); total bilirubin \