Differentiation of malignant liver tumors by software-based perfusion quantification with dynamic contrast-enhanced ultrasound (DCEUS)

BACKGROUND: Enhancement patterns on contrast-enhanced ultrasound (CEUS) help to distinguish different liver tumors. OBJECTIVE: Assessing the diagnostic value of dynamic contrast-enhanced ultrasound (DCEUS) for the discrimination of different malignant liver lesions. METHODS: 148 malignant focal liver lesions were assessed prospectively with DCEUS (hepatocellular carcinoma = HCC; cholangiocellular carcinoma = CCC; pancreatic adenocarcinoma = PCA; breast cancer = BC; colorectal cancer = CRC; melanoma= MM). Focal-nodular-hyperplasias (FNH) served as a reference for benign lesions. DCEUS-clips were recorded continuously over three minutes. DCEUS-values were compared between the tumor entities. For better inter-individual comparability, perfusion kinetics were analyzed considering the perfusion characteristics of the surrounding liver parenchyma (Relative Signal Intensity = RSL: lesion-liver tissue/liver tissue) at different points in time. RESULTS: Absolute signal intensity in FNH showed a tendency towards higher values compared with malignant liver lesions [Peak Enhancement(a.u.): FNH 7111.4; HCC 549.9; CCC -6654.3; PCA -7307.9; BC -4562.4; CRC -10672.9; MM -3034.1]. Washout was significantly less in FNH versus PCA and CRC, and more pronounced and earlier in PCA and CRC versus HCC [RSI 30 seconds after PE-lesion(%): FNH +52; PCA -65; CRC -76; HCC -26]. Rise Time, Fall Time and mean-Transit-Time did not differ significantly. CONCLUSIONS: DCEUS-values reflect significant differences between malignant liver lesions, especially at peak enhancement and during the washout phases.