Quantitative assessment of tumour associated neovascularisation in patients with liver cirrhosis and hepatocellular carcinoma: role of dynamic-CT perfusion imaging

Abstract

Objective: To determine the value of perfusion computed tomography (CT-p) in the quantitative assessment of tumour-related neoangiogenesis processes in patients with hepatocellular carcinoma (HCC).

Materials and methods: Fifty-two biopsy proven HCC lesions were examined with dynamic CT investigations during injection of 50 mL of contrast agent (350 mgI/mL). A dedicated perfusion software which generated a quantitative map of arterial and portal perfusion by means of a colour scale was employed. The following parameters related to the blood microcirculation and tissue perfusion were calculated: hepatic perfusion (Perf), tissue blood volume (BV), hepatic perfusion index (HPI), arterial perfusion (AP), portal perfusion (PP), and time to peak (TTP). Perfusion parameters were statistically analysed, comparing neoplastic lesions with cirrhotic parenchyma.

Results: Perf, BV, HPI and AP values were higher (P < 0.001), whereas PP and TTP were lower (P < 0.001) in HCC relative to the surrounding liver. No significant correlation was found between perfusion parameters and HCC grade. Values of perfusion parameters in the cirrhotic liver of patients with and without HCC were not significantly different.

Conclusions: Our results suggest that CT-p can help in non-invasive quantification of tumour blood supply, related to the formation of new arterial structures (neoangiogenesis), which are essential for tumour growth.

Key points: Perfusion computed tomography (CT) enables depiction of tumour vascular physiology. Perfusion CT is non-invasive and is now quick to perform and analyse. Quantitative measurements of hepatic perfusion provide important information about hepatocellular carcinoma (HCC). Such perfusion CT data may help in the determination of the outcome of HCC. Perfusion CT can act as an in-vivo biomarker of tumour-related angiogenesis.