Objective: To investigate the correlation between enhancement patterns of intrahepatic cholangiocarcinoma (ICC) on contrast-enhanced ultrasound (CEUS) and pathological findings. Methods: The CEUS enhancement patterns of 40 pathologically proven ICC lesions were retrospectively analysed. Pathologically, the degree of tumour cell and fibrosis distribution in the lesion was semi-quantitatively evaluated. Results: 4 enhancement patterns were observed in the arterial phase for 32 massforming ICCs: peripheral rim-like hyperenhancement (n519); heterogeneous hyperenhancement (n56); homogeneous hyperenhancement (n53); and heterogeneous hypo-enhancement (n54). Among the four enhancement patterns, the differences in tumour cell distribution were statistically significant (p,0.05). The hyperenhancing area on CEUS corresponded to more tumour cells for mass-forming ICCs. Heterogeneous hyperenhancement (n52) and heterogeneous hypo-enhancement (n52) were observed in the arterial phase for four periductal infiltrating ICCs. In this subtype, fibrosis was more commonly found in the lesions. Heterogeneous hyperenhancement (n51) and homogeneous hyperenhancement (n53) were observed in the arterial phase for four intraductal growing ICCs. This subtype tended to have abundant tumour cells. Conclusion: The CEUS findings of ICC relate to the degree of carcinoma cell proliferation at pathological examination. Hyperenhancing areas in the tumour always indicated increased density of cancer cells.

ABSTRACT. The aim of this study was to evaluate the imaging features of hepatic angiomyolipoma (AML) on contrast-enhanced ultrasound (CEUS). The imaging features of 12 pathologically proven hepatic AML lesions in 10 patients who had undergone baseline ultrasound (BUS) and CEUS examinations were evaluated retrospectively. The enhancement extent, pattern and dynamic change, along with the enhancement process, on CEUS were analysed. The diagnostic results of BUS and CEUS before pathological examination were also recorded. The results showed that 75% (9/12) of the AML lesions exhibited mixed echogenicity on BUS and most showed remarkable hyperechogenicity in combination with a hypoechoic or anechoic portion. Arterial flow signals were detected in 75% (9/12) of the lesions on colour Doppler imaging. On CEUS, 66.7% (n58) of the 12 lesions exhibited hyperenhancement in the arterial phase, slight hyperenhancement (n52) or isoenhancement (n56) in the portal phase, and slight hyperenhancement (n51) or isoenhancement (n57) in the late phase. Three (25%) lesions exhibited hyperenhancement in the arterial phase and hypoenhancement in both portal and late phases. One (8.3%) lesion exhibited hypoenhancement throughout the CEUS process. Before pathological examination with BUS, only 3 (25%) lesions were correctly diagnosed as hepatic AML. Conversely, on CEUS, correct diagnoses were made for 66.8% (8/12) of hepatic AMLs. Therefore, arterial hyperenhancement and subsequent sustained enhancement on CEUS were found in the majority of hepatic AMLs. The combination of BUS and CEUS leads to the correct diagnosis in the majority of hepatic AMLs, and is higher than the success rate achieved by BUS alone.