Hepatocellular carcinoma (HCC) is one of the most common malignant tumors with a poor prognosis. Interventional therapy serves as a main therapeutic approach for patients with unresectable HCC (uHCC). This study aimed to investigate the impact of post-interventional blood ammonia (BLA) levels on the prognosis of uHCC patients, so as to provide a reference for clinical risk stratification and individualized treatment.

A retrospective study was conducted, enrolling patients with uHCC admitted to our hospital from October 2020 to June 2025. According to the BLA levels within 1 week after interventional therapy, the patients were divided into the BLA < 50 μmol/L group and the BLA ≥ 50 μmol/L group. The clinical characteristics, interventional treatment modalities (hepatic arterial infusion chemotherapy [HAIC] or transcatheter arterial chemoembolization [TACE]), and laboratory indicators of the patients were collected. The Kaplan-Meier method was used for survival analysis, and the Cox proportional hazards regression model was applied to analyze the prognostic factors. 

A total of 209 patients was enrolled in this study, including 178 males (85.2%), the mean age was 56.6±9.5 years. By the last follow-up, 110 patients were still alive and 99 had died. The objective response rate (ORR) and disease control rate (DCR) in the BLA ≥ 50 μmol/L group were significantly lower than those in the BLA < 50 μmol/L group after interventional therapy (ORR: 12.2% vs. 24.4%, P=0.046; DCR: 28.1% vs. 48.1%, P=0.004). Survival analysis showed that the overall survival (OS) and progression-free survival (PFS) in the BLA ≥ 50 μmol/L group were significantly shortened (P<0.05). Multivariate Cox regression analysis revealed that BLA ≥ 50 μmol/L (HR=1.568, 95%CI: 1.047–2.347, P=0.029) was an independent risk factor for prognosis, while treatment with HAIC (HR=0.645, 95%CI: 0.421–0.989, P=0.044) was an independent protective factor. 

Elevated BLA (≥ 50 μmol/L) after interventional therapy is an independent risk factor for poor prognosis in patients with uHCC, and HAIC treatment may improve the survival of such patients. Monitoring post-interventional BLA levels is conducive to risk stratification and guiding clinical intervention.