Biomarker and Mechanism Study of Systemic Therapy in Unresectable HCC

The goal of this observational study is to evaluate the safety and efficacy of systemic therapies and identify predictive molecular biomarkers in patients with intermediate to advanced stage or unresectable hepatocellular carcinoma (HCC). The main questions it aims to answer are:What is the objective response rate (ORR) of systemic therapy regimens in this patient population? Which 3-4 specific biomarkers (including tumor or peripheral blood-derived genes, proteins, ctDNA, and immune cell subsets) can reliably predict the efficacy of systemic treatment?

Inclusion Criteria: * Histologically or cytologically confirmed hepatocellular carcinoma (HCC), or meeting the clinical diagnostic criteria of the "Guidelines for Diagnosis and Treatment of Primary Liver Cancer (2024 Edition)" issued by the National Health Commission of China. * Assessed by the investigator as unsuitable for surgical resection, or having intermediate to advanced stage HCC. Intermediate to advanced HCC is defined as Barcelona Clinic Liver Cancer (BCLC) stage B/C or China Liver Cancer (CNLC) stage IIa/IIb/IIIa/IIIb. * Child-Pugh liver function class A or a score of 7. Eastern Cooperative Oncology Group (ECOG) performance status score of 0 to 2. * Willing to receive targeted therapy combined with immunotherapy or dual immunotherapy, and signed the informed consent form (applicable to the prospective cohort). * Adequate bone marrow and organ function, meeting the following laboratory indicators: Absolute neutrophil count (ANC) \>= 1.0x10\^9/L without the use of granulocyte colony-stimulating factor within the past 14 days; Platelets \>= 50x10\^9/L without blood transfusion within the past 14 days; Hemoglobin \>= 90g/L without blood transfusion or erythropoietin use within the past 14 days; Total bilirubin \= 28g/L without human serum albumin or plasma infusion within the past 14 days; Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) \