On the basis of previous studies, this study intends to explore the efficacy of preoperative oral administration of Lactobacillus reuteri (Lr) combined with preoperative neoadjuvant/conversion therapy in patients with primary resectable hepatocellular carcinoma (HCC). We hypothesize that this combination represents a novel, microbiota-based therapeutic strategy to facilitate perioperative hepatic recovery and improve long-term survival outcomes.

This study is an open-label, randomized, blank-controlled clinical trial. Patients undergoing liver resection were randomly allocated to one of two groups. The intervention group received preoperative oral Lactobacillus reuteri (Lr) supplementation alongside neoadjuvant/conversion immunotherapy. The control group received preoperative neoadjuvant/conversion immunotherapy alone. Fecal and peripheral blood samples will be collected at baseline (pre-medication), 3 days prior to surgery, and at 5 days, 1, 3, 6, 9, 12, 18, and 24 months postoperatively. Intraoperative liver tissue samples will also be obtained. Statistical analyses will be performed to compare intergroup differences in postoperative liver function recovery, overall survival, hepatic and peripheral immune markers, and gut microbiota composition.

This study aims to develop adjuvant strategies to enhance therapeutic outcomes for HCC patients undergoing preoperative neoadjuvant/conversion immunotherapy.

Inclusion Criteria:

1. Understanding and voluntarily signing the informed consent form for this study;
2. Age≥18 years and ≤75 years; gender not restricted;
3. Histologically (pathologically), cytologically, or radiologically confirmed hepatocellular carcinoma (HCC);
4. Patients who require preoperative immune checkpoint inhibitor (ICI) combination therapy followed by potentially curative hepatectomy;
5. No prior systemic therapy for HCC, including chemotherapy, targeted therapy, or immunotherapy had been administered before enrollment.;
6. Patients with a history of prior curative surgery or curative ablation are allowed, except for those with recurrence within 2 years post-curative treatment or prior receipt of other local therapies;
7. At least one measurable lesion meets RECIST v1.1 criteria;
8. Child-Pugh liver function rating: grade A or B;
9. The expected survival period is greater than 3 months;
10. Patients must be able to take food orally independently;
11. Preoperative ECOG physical condition score 0-1 points;
12. Normal coagulation function, no activebleeding or thrombotic diseases; A. International standardized ratio INR≤1.5×ULN; B. Partial thromboplastin time APTT≤1.5×ULN;
13. Has adequate organ and bone marrow function, laboratory test values within 7 days prior to enrollment meet the following requirements (no blood components, cell growth factors, albumin, or other corrective drugs are allowed within 14 days prior to laboratory test), as follows: 1) Blood routine: absolute neutrophil count≥1.5×109/L; platelet count≥75×109/L; hemoglobin conten≥9.0 g/dL. 2) Liver function: serum total bilirubin≤2× upper limit of normal value (ULN); alanine aminotransferase and aspartate transferas≤5×ULN; Serum albumin ≥28 g/L; alkaline phosphatase≤5×ULN. 3) Renal function: serum creatinine≤1.5×ULN or clearance of creatinine≥50mL/min(Cockcroft-Gault formula); Urine routine results showed that urine protein <2+; For patients with urine protein ≥2+ on routine urine tests at baseline, 24-hour urine collection and 24-hour protein quantification <1g should be performed.

Exclusion Criteria:

1. Inability to comply with the study protocols or procedures;
2. Known intrahepatic cholangiocarcinoma, sarcomatoid hepatocellular carcinoma, mixed cell carcinoma (ICC more than 30%) and fibrolaminar cell carcinoma
3. Hepatic encephalopathy, hepatorenal syndrome, or severe decompensated cirrhosis;
4. Planned use of probiotics, yogurt, or bacterial-fortified foods during the treatment period;
5. Use of probiotics or antibiotic within 2 months before the trial;
6. Patients with severe mental illness;
7. Patients under fasting or fluid restriction (e.g., complete bowel obstruction, active gastrointestinal bleeding, etc.);
8. Patients with chronic digestive system diseases, such as irritable bowel syndrome, malabsorption syndrome, inflammatory bowel disease, or ileostomy;
9. Allergy to the trial product or its components, inability to swallow tablets, unwillingness or inability to receive intravenous administration, or a history of severe infusion-related reactions to monoclonal antibodies or any other active malignancies during the initial study treatment administration;
10. Participants in other drug, dietary supplement, probiotic, or prebiotic clinical studies within the past 1 months prior to enrollment
11. Pregnant or lactating women;
12. History of other malignancies within the past 5 years, except for completely resected basal cell carcinoma or squamous cell carcinoma of the skin, or cervical carcinoma in situ;
13. Any medical or non-medical condition that the researcher deems unsuitable for participation.