QL1706 in Combination With Bevacizumab and RALOX HAIC for Hepatocellular Carcinoma With Vp3/4 PVTT

Inclusion Criteria: 1. Voluntarily sign the informed consent form; 2. Aged ≥ 18 years, male and female subjects are both eligible; 3. Clinically or pathologically confirmed hepatocellular carcinoma (HCC), with no prior systemic anti-tumor therapy for HCC (including but not limited to molecular targeted therapy, systemic chemotherapy, immunotherapy such as anti-PD-1/PD-L1/CTLA-4 monoclonal antibodies, etc.); 4. Complicated with Type VP3 or VP4 portal vein tumor thrombosis (PVTT); 5. Confirmed to have at least one measurable target lesion by imaging examination during the screening period in accordance with RECIST v1.1 criteria. The measurable lesions should not have received local treatment such as radiotherapy (lesions within the area of previous local treatment can also be selected as target lesions if disease progression is confirmed); 6. Child-Pugh score ≤ 7 points (Child-Pugh class A-B); 7. The maximum diameter of liver tumor ≥ 7 cm; 8. ECOG performance status 0 to 1; 9. Expected survival time ≥ 12 weeks; 10. Function of vital organs meeting the following requirements: Absolute neutrophil count (ANC) ≥ 1.5×10⁹/L; Platelet count ≥ 50×10⁹/L; Hemoglobin ≥ 90 g/L; Serum albumin ≥ 29 g/L; Bilirubin ≤ 2 × upper limit of normal (ULN); Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤ 5 × ULN, alkaline phosphatase (AKP) ≤ 5 × ULN; Serum creatinine ≤ 1.5 × ULN or creatinine clearance rate (CrCl) ≥ 50 mL/min calculated by the Cockcroft-Gault formula; 11.Eligible patients with reproductive potential (males and females) must agree to use a reliable contraceptive method (hormonal, barrier method or abstinence) with their partners during the trial and for at least 180 days after the last dose; female patients of childbearing potential must have a negative serum pregnancy test within 7 days prior to the first study medication administration. Exclusion Criteria: 1. Histologically or cytologically confirmed fibrolamellar hepatocellular carcinoma, sarcomatoid hepatocellular carcinoma, cholangiocellular carcinoma, mixed hepatocellular carcinoma, etc.; 2. Active autoimmune disease, or a history of autoimmune disease with potential for recurrence (including but not limited to: autoimmune hepatitis, interstitial pneumonia, uveitis, enteritis, hypophysitis, vasculitis, nephritis, hyperthyroidism, hypothyroidism \[patients whose condition is controllable only with hormone replacement therapy are not excluded\]); Note: Patients with dermatological diseases that do not require systemic treatment (e.g., vitiligo, psoriasis, alopecia), type 1 diabetes with good glycemic control under insulin therapy, or asthma that achieved complete remission in childhood and requires no intervention in adulthood are eligible for enrollment; patients with asthma requiring medical intervention with bronchodilators are ineligible. 3. Administration of immunosuppressants or systemic hormonal therapy for immunosuppressive purposes within 2 weeks prior to the first study medication (dose \> 10 mg/day prednisone or an equivalent dose of other hormones); 4. Current interstitial pneumonia or interstitial lung disease, a history of interstitial pneumonia or interstitial lung disease requiring hormonal therapy, or other pulmonary fibrosis, organizing pneumonia (e.g., bronchiolitis obliterans), pneumoconiosis, drug-related pneumonia, idiopathic pneumonia that may interfere with the judgment and management of immune-related pulmonary toxicity; patients with evidence of active pneumonia on screening CT or severe impairment of pulmonary function are excluded. Radiation pneumonitis within the radiation field is permitted; 5. Confirmed active pulmonary tuberculosis. For subjects with suspected active pulmonary tuberculosis, a definitive diagnosis shall be made based on chest imaging, sputum examination, and clinical symptoms and signs; 6. Known hypersensitivity to the active ingredients or excipients of the study drugs, or a history of severe hypersensitivity to any other monoclonal antibody or anti-angiogenic targeted drugs; 7. Known history of central nervous system (CNS) metastasis or hepatic encephalopathy; 8. A history of allogeneic stem cell transplantation or solid organ transplantation; 9. Moderate to severe ascites with clinical symptoms requiring therapeutic paracentesis or drainage (except for patients with only a small amount of ascites shown by imaging without clinical symptoms), or uncontrolled moderate to large pleural effusion or pericardial effusion; 10. Severe cardiovascular and cerebrovascular diseases, including but not limited to: (1) Severe cardiac rhythm or conduction abnormalities (e.g., ventricular or supraventricular arrhythmias requiring clinical intervention, grade Ⅱ-Ⅲ atrioventricular block), QTcF interval ≥ 450 ms (males) or QTcF interval ≥ 470 ms (females) (if the QTcF interval is abnormal at screening, two additional tests shall be performed at an interval of at least 5 minutes, and the average value shall be taken); unstable angina pectoris, etc.; (2) Acute coronary syndrome, congestive heart failure, aortic dissection, stroke, transient ischemic attack (TIA) or other grade 3 and above cardiovascular and cerebrovascular events within 6 months prior to the first study medication; (3) New York Heart Association (NYHA) cardiac function classification ≥ grade II or left ventricular ejection fraction (LVEF) \< 50%; (4) Poorly controlled hypertension (systolic blood pressure ≥ 160 mmHg and/or diastolic blood pressure ≥ 100 mmHg after treatment with two or more antihypertensive drugs); 11.Coagulation dysfunction (INR \> 2.0, prothrombin time (PT) prolonged by more than 6 seconds), with obvious bleeding tendency or other evidence of major coagulation disorders: clinically significant hemoptysis or tumor bleeding of any cause within 2 weeks prior to the first study medication; a history of thrombosis or embolism within 6 months prior to the first study medication; therapeutic anticoagulant thera