Hepatic Arterial Blood Flow Modulation in Patients with Hepatocellular Carcinoma: A Pilot Study of the Influence of Intraarterial Norepinephrine Assessed with CT Perfusion

PURPOSE: This pilot study aims to evaluate the effect of hepatic intraarterial norepinephrine injection in vasculature modulation for hepatocellular carcinoma (HCC) tumors. MATERIALS AND METHODS: This is a single-center prospective study of patients with HCC with proven single-lobe tumors > 3 cm. Eight patients were included, with a mean age of 63 y ± 8. All patients had Barcelona Clinic Liver Cancer stage B HCC and an Eastern Cooperative Oncology Group performance status of 0. Mean tumor size was 6.1 cm ± 1.8; all tumors were hypervascular. Patients underwent CT hepatic perfusion before and after injection of 24 μg of norepinephrine intraarterially (4 μg/mL; total 6 mL injected at a rate of 1 mL/s). Color-coded perfusion maps were used to assess the effects of local therapy on hepatic perfusion values. Tumor-to-liver ratio (TLR) was calculated from the ratio of tumor perfusion to background liver perfusion value. RESULTS: Seven of 8 patents had significant (P = .04) absolute increase in tumor perfusion vs background liver, varying from incremental (-2 mL/min/100 mL) to 290 mL/min/100 mL. There was a nonsignificant increase in TLR from 2.7 ± 1.3 to 2.9 ± 1.4 after norepinephrine injection (P = .8). Mean peak time to maximal increase in tumor perfusion after injection was 6.1 s (range, 4.5-9.1 s). Norepinephrine injection was well tolerated without major adverse events. CONCLUSIONS: Norepinephrine causes increased blood flow toward HCC tumors, but with a corresponding smaller increase in blood flow to noncancerous liver tissue, with no observed systemic side effects.