ABSTRACT
Objective To investigate the contrast-enhanced ultrasonography appearances characteristics of intrahepatic peripheral cholangiocarcinoma( ICC) and to improve the diagnosis level of ICC on contrast-enhanced ultrasonography . Methods Thirty cases with ICC confirmed by pathological examinations of surgeries were retrospectively analyzed for findings of ultrasonography , clinic and pathology ,to explore the typical contrast-enhanced ultrasonography appearances and the correlation with pathological differentiation . ResultsOn contrast-enhanced ultrasonography , 30 lesions showed enhancement on the arterial phase and appeared hypo-echoic enhancement on the portal phase ,which displayed fast-in and fast-out" enhancement pattern . During the hepatic arterial phase of contrast-enhanced ultrasonography ,10 lesions showed peripheral enhancement ,10 lesions showed relatively homogeneous hyper-enhancement ,6 lesions showed heterogeneous enhancement ,2 lesions showed iso-enhancement ,and 2 lesions showed hypo-enhancement . To the 30 lesions ,the average initial time of enhancement was ( 18 .81 ± 4 .66)s (12 －28 s) ,the average time of washing-out was (36 .00 ± 12 .30) s (18 －60 s) . There was no significant difference in time of washing-in and washing-out among different pathological differentiation groups ( P＞0 .05) . Conclusions ICC often shows fast-in and fast-out" enhancement pattern on contrast-enhanced ultrasonography ,and the time of washing-out is generally in late arterial phase or early portal phase ,but there is no significant difference in time of washing-in and washing-out among different pathological differentiation groups .
ABSTRACT
PURPOSE: Liver transplant guidelines for diagnosing hepatocellular carcinoma (HCC) do not mandate pathologic confirmation; instead, 'classic' imaging features alone are deemed satisfactory. Intrahepatic peripheral mass forming cholangiocarcinoma (IHPMCC) is a relative contraindication for transplantation due to high rate of recurrence and poor prognosis. This study examines the imaging findings of IHPMCC, to aid in the identification and differentiation from potentially confounding cases of HCC. METHODS: After IRB approval, 43 tissue-proven cases of IHPMCC on multiphase CT were retrospectively reviewed by 2 fellowship-trained radiologists. Tumor size, presence of cirrhosis, tumor capsule, vascular invasion, tumor markers, and enhancement pattern were assessed. A grading system was assigned as determined by enhancement pattern to background liver on arterial, portal venous, and equilibrium phases, ranging from typical HCC to typical IHPMCC enhancement pattern. RESULTS: Analysis based on our grading system shows 5 (11.6%) tumors demonstrating grade 1-2 enhancement, 9 (21%) grade 3-4 enhancement, and 29 (67.4%) grade 5 enhancement. Kruskal-Wallis test comparing CA19-9 between the five groups, Wilcoxin rank-sum test comparing tumor markers with presence or absence of tumor capsule, vascular invasion and cirrhosis, and nonparametric Pearson's correlation coefficient comparing tumor markers to tumor size were not statistically significant (p > 0.05). CONCLUSION: Typical enhancement pattern of IHPMCC consisting of arterial phase hypoenhancement with progressive, centripetal-delayed enhancement is present in the majority of cases (68%). Five cases (11.7%) showed enhancement features potentially mimicking HCC, all of which are under 3.5 cm in size. Thus, small hyperenhancing lesions in a cirrhotic liver should be carefully scrutinized in light of differing therapy options from HCC, particularly in transplant situations.
