Shear Wave Elastography For Differentiating Biliary Hamartoma From Liver Cirrhosis: A Case Series Study And Literature Review

The biliary hamartoma (BH), so called von Meyenburg complex, is a rare congenital disease of bile duct malformation. In clinical practice, the majority is discovered incidentally. It was believed that typical image finding from cross-sectional images could help us make a correct diagnosis without histology. Ultrasound shear wave elastography (SWE) had been validated as a noninvasive method for estimating liver fibrosis in patients with liver diseases. The aim of the present study is to explore the ability of SWE in the differentiation of BH from liver cirrhosis. We reported a case series of 14 cases that were diagnosed as BH and followed up at the clinic of the Chimei Medical Center from January 2016 to December 2017. These cases were found incidentally on routine ultrasonography examination because of the extraordinary coarse liver parenchymal pattern, without the typical findings of portal hypertension. The SWE is performed at the same time BH was suspected or gained retrospective after BH was confirmed by magnetic resonance imaging (MRI)/magnetic resonance cholangiopancreatography (MRCP). SWE classifies the entity as no fibrosis (F0), mild fibrosis (F1), severe fibrosis (F2), significant fibrosis (F3), and cirrhosis (F4). MRI or MRCP further confirmed the final diagnosis of all the inclusive cases. We also collected and analyzed the clinical, laboratory, and image characteristics. Fourteen patients were identified and enrolled in our study. The median age was 61.3 years old (range: 37-81). Echo comet-tail sign and equal sign of liver parenchymal were noted in 13 patients (13/14 = 92.9%). Twelve patients (12/14 = 85.7%) underwent SWE, and nine patients were included in the F0-F1 group. Only one was indicated to have significant fibrosis (F3), but the MRI did not demonstrate cirrhosis. Seven patients had chronic virus hepatitis (five hepatitis B and two hepatitis C patients) on review of their medical history records. We noticed the presentation of elevated serum level of gamma-GT in three cases and CA19-9 in two cases. In our cases, no neoplastic transformation episode was noted during the follow-up periods. In cases of overt coarse echo pattern of liver parenchyma, without other signs of portal hypertension, BH should be considered in differential diagnoses. SWE could be used as a differentiation tool to help exclude cirrhosis.