Risk stratification model for predicting distant metastasis after hepatectomy for hepatocellular carcinoma: A multi-institutional analysis.

Distant metastasis after hepatectomy for hepatocellular carcinoma (HCC) significantly impairs long-term outcome. This study aimed to identify patterns, risk factors, and develop a prediction model for distant metastasis at first recurrence following HCC resection. This multi-center retrospective study included patients undergoing curative hepatectomy for HCC. Risk factors for distant metastasis were identified using Cox regression. A nomogram was constructed and validated using the concordance index (C-index) and calibration curves. Among 2,705 patients, 1,507 experienced recurrence, with 342 (22.7 per cent) developing distant metastasis. Common metastatic sites included extrahepatic vessels (36.2 per cent), lungs (26.0 per cent), and lymph nodes (20.8 per cent). Patients with distant metastasis had significantly worse 5-year overall survival compared to those with intrahepatic recurrence (9.1 versus 41.1 per cent, p < 0.001). Independent risk factors included preoperative tumor rupture, tumor size over 5.0 cm, multiple tumors, satellite nodules, macro- and microvascular invasion, narrow resection margin, and intraoperative blood transfusion. The nomogram demonstrated excellent discrimination (C-index > 0.85) and accurately stratified patients into three risk categories. In conclusion, distant metastasis at first recurrence following HCC resection was associated with poor prognosis. The proposed nomogram facilitates accurate prediction of distant metastasis, potentially informing personalized postoperative monitoring and interventions for high-risk patients.