Gadobenate dimeglumine-enhanced MRI of intraductal papillary mucinous tumor of the bile ducts

Mucobilia: An Unusual Cause of Persistent Jaundice

Mucobilia is defined as the abnormal secretion of copious amounts of mucus from within the bile ducts, manifesting as obstructive jaundice or cholangitis. A spectrum of mucin-producing hepatobiliary and pancreatic neoplasms have been associated with mucobilia. We report the case of a 63-year-old male with an intestinal type of intraductal papillary neoplasm of the intrahepatic bile duct.

Mucinous cystic neoplasm of the liver with biliary communication: an exception to the current classification

Cystic neoplasms of the liver are rare tumours. According to the recent WHO classification, they are classified into mucinous cystic neoplasm and intraductal papillary neoplasm based on the presence of ovarian-like stroma and biliary communication. We report two rare cases of mucinous cystadenoma of the liver with biliary communication and discuss the shortcomings of current classification.

Diagnostic performance of CT and MRI in distinguishing intraductal papillary neoplasm of the bile duct from cholangiocarcinoma with intraductal papillary growth

OBJECTIVES

We aimed to evaluate the diagnostic performance of CT and MRI for distinguishing intraductal papillary neoplasm of the bile duct (IPNB) from cholangiocarcinoma (CC) with intraductal papillary growth (IPG).

METHODS

Forty-two patients with either IPNB or CC with IPG proven by histopathology were independently reviewed in retrospect. Strict criteria for diagnosis of IPNB included presence of the designated imaging features as follows: local dilatation of the bile duct, nodule within the dilated bile duct, growing along the interior wall of bile duct. Any lesion that was not consistent with the criteria was classified as CC with IPG. Sensitivity, specificity, positive and negative predictive values for characterization of IPNB were calculated, and k test was used to assess the level of agreement.

RESULTS

Two imaging reviewers correctly identified 21 of 26 (80.8%) and 22 of 26 (84.6%) IPNB cases, respectively. Alternatively, they correctly identified 14 of 16 (87.5%) and 15 of 16 (93.8%) CC with IPG, respectively. Agreement between the two reviewers was perfect (k = 0.81) for the diagnosis of IPNB and differentiation from CC with IPG.

CONCLUSIONS

By using our designated diagnostic criteria of CT and MRI, IPNB can be accurately identified and possible to be distinguished from CC with IPG.

KEY POINTS

• IPNB can accurately be identified by using defined diagnostic criteria at CT/MRI. • IPNB has some characteristic CT and MR imaging features. • IPNB is a rare entity; up until now it might have been misdiagnosed.

Magnetic resonance evaluations of biliary malignancy and condition at high-risk for biliary malignancy: Current status

Tumors of the biliary tree are relatively rare; but their incidence is rising worldwide. There are several known risk factors for bile duct cancers, and these are seem to be associated with chronic inflammation of the biliary epithelium. Herein, 2 risk factors have been discussed, primary sclerosing cholangitis and reflux of pancreatic juice into the bile duct, as seen in such as an abnormal union of the pancreatic-biliary junction because magnetic resonance imaging (MRI) is used widely and effectively in the diagnosis of these diseases. When biliary disease is suspected, MRI can often help differentiate between benignity and malignancy, stage tumors, select surgical candidates and guide surgical planning. MRI has many advantages over other modalities. Therefore, MRI is a reliable noninvasive imaging tool for diagnosis and pre-surgical evaluation of bile duct tumors. Nowadays remarkable technical advances in magnetic resonance technology have expanded the clinical applications of MRI in case of biliary diseases. In this article, it is also discussed how recent developments in MRI contributes to the diagnosis of the bile duct cancer and the evaluation of patients with risk factors affecting bile duct cancer.

Spectrum of mucin-producing neoplastic conditions of the abdomen and pelvis: Cross-sectional imaging evaluation

Various mucin-producing neoplasms originate in different abdominal and pelvic organs. Mucinous neoplasms differ from non-mucinous neoplasms because of the differences in clinical outcome and imaging appearance. Mucinous carcinoma, in which at least 50% of the tumor is composed of large pools of extracellular mucin and columns of malignant cells, is associated with a worse prognosis. Signet ring cell carcinoma is characterized by large intracytoplasmic mucin vacuoles that expand in the malignant cells with the nucleus displaced to the periphery. Its prognosis is also generally poor. In contrast, intraductal papillary mucinous neoplasm of the bile duct and pancreas, which is characterized by proliferation of ductal epithelium and variable mucin production, has a better prognosis than other malignancies in the pancreaticobiliary tree. Imaging modalities play a critical role in differentiating mucinous from non-mucinous neoplasms. Due to high water content, mucin has a similar appearance to water on ultrasound (US), computed tomography (CT), and magnetic resonance imaging, except when thick and proteinaceous, and then it tends to be hypoechoic with fine internal echoes or have complex echogenicity on US, hyperdense on CT, and hyperintense on T1- and hypointense on T2-weighted images, compared to water. Therefore, knowledge of characteristic mucin imaging features is helpful to diagnose various mucin-producing neoplastic conditions and to facilitate appropriate treatment.

Usefulness of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance cholangiography for detecting mucin retention in bile ducts: a rare intraductal papillary mucinous neoplasm of the bile duct

We report a 75-year-old man with radiological evidence of a 4.5 × 3.0 cm cystic mass and polypoid masses in the left hepatic lobe. Study of surgical specimens returned a definitive diagnosis of intraductal papillary mucinous neoplasm of the bile duct (IPMN-B). IPMN-B, thought to be the counterpart of intraductal papillary mucinous neoplasm of the pancreas (IPMN), is frequently associated with marked mucin production. We describe a rare case of IPMN-B in which gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance cholangiography was useful for detecting mucin retention in the bile ducts.

MR appearance of normal and abnormal bile: correlation with imaging and endoscopic finding

Identification of abnormal bile related to various pathological processes in the pancreaticobiliary tract can be important in the diagnosis of disease and the determination of appropriate treatment. Magnetic resonance (MR) imaging can allow comprehensive evaluation of abnormal bile because MR usually provides better tissue characterization than other imaging modalities. A high-intensity signal from bile is frequently encountered on T1-weighted images and can be seen in concentrated bile, sludge, stones, or hemobilia. Contrast-enhanced MR features, such as inhomogeneous hepatic enhancement in the arterial phase and papillitis or mild-to-moderate bile duct wall thickening with enhancement, along with clinical characteristics, may suggest clinically significant bile, such as sludge or purulent bile, rather than merely concentrated bile. A history of trauma and appropriate imaging findings in the hepatobiliary tract can support a diagnosis of hemobilia. MR imaging may assist in diagnosing intraductal papillary mucinous neoplasm of the bile duct via detection of an intraductal mass or several indirect signs, suggesting a large amount of mucin. Additionally, Gd-EOB-DTPA-enhanced MR may delineate mucin as a filling defect surrounding hyperintense bile. A floating filling defect on all MR sequences is helpful in discriminating pneumobilia from other intraluminal filling defects. Familiarity with the various different MR features of abnormal bile signals can therefore facilitate accurate diagnosis and treatment.

Biliary cystadenoma revealed by obstructive jaundice

Biliary cystadenoma is a rare cystic tumour of the liver that can be difficult to differentiate from other types of benign hepatic cysts. We report the case of a 32-year-old woman who presented with obstructive jaundice due to a large cystic lesion of the left hepatic lobe. Resection of the mass revealed a mucinous cystadenoma with protrusion of a pedunculated extension into the left hepatic duct and the common bile duct. We describe the clinical features, the radiological findings, the surgical management and the pathology of this rare entity.