Perfusion CT in cirrhotic patients with early stage hepatocellular carcinoma: Assessment of tumor-related vascularization

Purpose: To assess the value of CT-perfusion in determining the quantitative vascularization features of early hepatocellular carcinoma (HCC) in cirrhotic patients. Materials and methods: A total of 35 cirrhotic patients with single histologically proven HCC not exceeding 3 cm in diameter underwent conventional triple-phase multidetector computed tomography (MDCT) examination. All patients were also examined with CT-perfusion (CTp) technique after i.v. injection of 50 mL of iodinated contrast. Data were analyzed using a dedicated software which generated a quantitative map of liver parenchyma perfusion. The following parameters were assessed: hepatic perfusion (HP); blood volume (BV); arterial perfusion (AP); time to peak (TTP) and hepatic perfusion index (HPI). Univariate Wilcoxon signed rank test was used for statistical analysis. Results: In the 35 HCCs evaluated, the following quantitative data were obtained: HP (mL/s/100 g): median = 47.0 (1stqt = 35.5; 3stqt = 61.2); BV (mL/100 mg): median = 22.5 (1stqt = 18.4; 3stqt = 27.7); AP (mL/min): median = 42.9 (1stqt = 35.8; 3stqt = 55.6); HPI(%): median = 75.3 (1stqt = 63.1; 3stqt = 100); TTP(s): median = 18.7 (1stqt = 16.8; 3stqt = 24.5). Perfusion values calculated in cirrhotic liver parenchyma were HP: median = 10.3 (1stqt = 9.1; 3stqt = 13.2); BV: median = 11.7 (1stqt = 9.6; 3stqt = 15.5); AP: median = 10.4 (1stqt = 8.6; 3stqt = 11.3); HPI: median = 17.5 (1stqt = 14.3; 3stqt = 19.7); TTP: median = 44.6 (1stqt = 40.3; 3stqt = 50.1). HP, BV, HPI and AP were found to be significantly higher in HCC lesion than in liver parenchyma (p < 0.001), while TTP was significantly lower (p < 0.001). Conclusion: CT-perfusion technique allows obtaining quantitative information about tumor-related vascularization of early HCC, in patients with liver cirrhosis.