• Signed written informed consent and able to comply with scheduled visits and related procedures;

• Age ≥18 and ≤75 years, regardless of gender;

• Patients with HCC who meet the clinical diagnostic criteria of China's Guidelines for the Diagnosis and Treatment of Hepatocellular Carcinoma (2022 Edition) or are diagnosed by biopsy, and have at least one measurable lesion according to the mRECIST criteria;

• Presence of portal vein tumor thrombus (PVTT) of Cheng's type I/II/III, with the primary tumor being resectable;

• Child-Pugh score of Class A;

• Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) of 0-1;

• No prior antitumor treatment (such as surgery, radiotherapy, TACE, ablation, chemotherapy, targeted therapy, immunotherapy, or systemic therapy).

• For patients with hepatitis B virus (HBV) infection, testing for HBV-DNA is required; direct treatment initiation is allowed if HBV-DNA ≤2000 IU/mL; if HBV-DNA \>2000 IU/mL, antiviral therapy should be administered for one week before starting the treatment; all HBV positive patients will receive continuous antiviral treatment throughout the study; patients with hepatitis C virus (HCV) RNA positive must undergo antiviral treatment as per the guidelines;

• Participants must provide a fresh tumor biopsy sample during the screening period (can be waived after discussion with the medical monitor) and blood samples for monitoring immune cells, cytokine levels, and other relevant immune status in the tumor microenvironment;

⁃ Expected survival of ≥12 weeks;

⁃ Adequate organ and marrow function, as defined by the following laboratory values:

∙ Hematology: Absolute Neutrophil Count ≥1.5×109/L; Platelets ≥80×109/L; Hemoglobin ≥90g/L;

‣ Liver function: Total bilirubin ≤3× upper limit of normal (ULN); Alanine Aminotransferase and Aspartate Aminotransferase ≤5×ULN; Serum albumin ≥30g/L;

‣ Renal function: Serum creatinine (Cr) ≤1.5×ULN, or for patients with Cr \>1.5×ULN, creatinine clearance (CCr) ≥45 mL/min (Cockcroft-Gault formula); Urinalysis showing proteinuria \<2+; For participants with baseline proteinuria ≥2+, a 24-hour urine collection and quantitative protein \<1g is required;

‣ Coagulation: International Normalized Ratio or APTT ≤1.5×ULN;

⁃ Females of childbearing potential must agree to abstain from heterosexual intercourse or use effective contraception from signing the informed consent until at least 120 days after the last dose of study medication. They must have a negative serum HCG test within 1 week before treatment and must not be breastfeeding. Females who have not reached menopause (≥12 months of amenorrhea without an alternative medical cause) and have not undergone sterilization (e.g., hysterectomy, bilateral salpingectomy, or bilateral oophorectomy) are considered to be of childbearing potential;

⁃ Male participants with partners of childbearing potential must agree to abstain from heterosexual intercourse or use reliable and effective contraceptive methods from the time of signing the informed consent until at least 120 days after the last dose of study medication. During the same period, male participants must also agree not to donate sperm. Male subjects whose partners are pregnant must use condoms and do not need to use other contraceptive methods.