Perfusion Characteristics of Hepatocellular Carcinoma at Contrast-enhanced Ultrasound: Influence of the Cellular differentiation, the Tumor Size and the Underlying Hepatic Condition.

This study aimed to analyze the influence of the cellular differentiation, the tumor size and the underlying hepatic condition on the enhancement pattern of hepatocellular carcinoma (HCC) on contrast-enhanced ultrasound (CEUS). 276 patients with single lesion ≤ 5 cm who underwent CEUS exam and were pathologically confirmed as HCC were retrospectively enrolled. Enhancement patterns, washout patterns, wash-in time and washout time were observed and recorded. During the arterial phase, more poorly differentiated HCCs (42.5%) and lesions > 3 cm (35.2%) performed inhomogeneous enhancement (p < 0.05). More well differentiated HCCs (63.4%) performed late washout or no washout while compared with moderately (37.8%) or poorly (24.1%) differentiated HCCs (p < 0.05). Poorly differentiated HCCs showed the shortest washout time (83.0 ± 39.8 s), moderately differentiated HCCs showed the moderate washout time (100.4 ± 52.1 s), and well differentiated HCCs showed the longest washout time (132.3 ± 54.2 s) (p < 0.05). Lesions > 3 cm (97.2 ± 51.3 s) washed out more rapidly than lesions ≤ 3 cm (113.9 ± 53.5 s) (p < 0.05). The dynamic enhancement procedure of HCC was influenced by the cellular differentiation and the tumor size. While, hepatic background showed no influence on the dynamic enhancement of HCC.