Sinusoidal injury and portal hypertension after hepatectomy for colorectal liver metastases: predictors, risk stratification, and clinical outcomes

INTRODUCTION: Sinusoidal obstruction syndrome (SOS) and early portal hypertension (ePHT) represent significant hepatic vascular complications following preoperative chemotherapy and liver resection for colorectal liver metastases (CRLM). This study aimed to identify predictors of SOS and ePHT and to develop a risk model for preoperative stratification. METHODS: A retrospective analysis was conducted in 108 patients undergoing hepatectomy for CRLM after ≥ 4 cycles of neoadjuvant chemotherapy combined with anti-EGFR or anti-VEGF therapy. SOS severity was graded histologically, and ePHT was defined by thrombocytopenia, splenomegaly, varices, or ascites within 3 months postoperatively. Logistic regression models identified predictors of moderate-to-severe SOS (G2-3) and ePHT. Predictive performance was assessed using receiver operating characteristic (ROC) analysis. RESULTS: Moderate-to-severe SOS occurred in 24.07% of patients and ePHT in 21.3%. Independent predictors of SOS were anti-VEGF therapy (protective, OR = 0.214; 95% CI 0.075-0.610; p = 0.004) and preoperative portal vein embolization (PVE) or ligation (risk factor, OR = 2.819; 95% CI 1.019-7.796; p = 0.046). The SOS predictive model showed good discrimination (AUC = 0.75). For ePHT, major hepatectomy (OR = 7.78; 95% CI 2.32-25.99; p < 0.001) and the calculated probability to SOS G2-3 (OR = 40.82; 95% CI 2.60-640.53; p = 0.008) were independent predictors (AUC = 0.80; specificity = 84.3%). Neither SOS nor ePHT significantly affected 90-day mortality (8.3%) or overall survival (p > 0.05). CONCLUSIONS: Major hepatectomy and chemotherapy-induced sinusoidal injury are key determinants of ePHT after CRLM resection. Anti-VEGF therapy exerts a protective endothelial effect, while PVE increases risk. Despite their incidence, neither SOS nor ePHT compromised survival, suggesting reversibility with optimized perioperative management.