Bile duct hamartomas. A report of two cases

Histopathologic Findings in Autopsies with Emphasis on Interesting and Incidental Findings-A Pathologist's Perspective

INTRODUCTION

Autopsy aids to the knowledge of pathology by unveiling the rare lesions which are a source of learning from a pathologist's perspective Some of them are only diagnosed at autopsy as they do not cause any functional derangement. This study emphasizes the various incidental lesions which otherwise would have been unnoticed during a person's life.

AIM

The aim of this study was to determine the spectrum of histopathological findings including neoplastic lesions related or unrelated to the cause of death. It was also aimed to highlight various incidental and interesting lesions in autopsies.

MATERIALS AND METHODS

A retrospective study of medicolegal autopsies for six years was undertaken in a tertiary care centre to determine the spectrum of histopathological findings including neoplastic lesions related or unrelated to the cause of death and to highlight various incidental and interesting lesions in autopsies. Statistical Analysis: Individual lesions were described in numbers and incidence in percentage.

RESULTS

The study consisted of a series of 269 autopsy cases and histopathological findings were studied only in 202 cases. The commonest cause of death was pulmonary oedema. The most common incidental histopathological finding noted was atherosclerosis in 55 (27.2%) cases followed by fatty liver in 40 (19.8%) cases. Neoplastic lesions accounted for 2.47% of cases.

CONCLUSION

This study has contributed a handful of findings to the pool of rare lesions in pathology. Some of these lesions encountered which served as feast to a pathologist are tumour to tumour metastasis, a case with coexistent triple lesions, Dubin Johnson syndrome, von Meyenburg complex, Multilocular Cystic Renal Cell Carcinoma (MCRCC), Autosomal Dominant Polycystic Kidney Disease (ADPKD), liver carcinod and an undiagnosed vaso-occlusive sickle cell crisis. Autopsy studies help in the detection of unexpected findings significant enough to have changed patient management had they been recognized before death.

Recurrent hepatobiliary sepsis in a patient with von Meyenburg complexes: a case report and review of the literature

The von Meyenburg complex (VMC) is a rare, congenital malformation of the ductal plate. It is typically asymptomatic and usually discovered incidentally. We report a unique case of recurrent life-threatening hepatobiliary sepsis caused by VMC and a review of the literature. A 62-year-old man presented with recurrent episodes of life-threatening hepatobiliary sepsis. Extensive investigations only showed that he has VMCs without any other source of sepsis or underlying immunodeficiency states. Despite prolonged courses of antibiotics which resolved each episode of sepsis, he suffers repeated recurrences of hepatobiliary sepsis. Liver transplantation is now being considered in view of his refractoriness to medical therapy. As VMC can present with severe hepatobiliary sepsis, it is therefore essential to recognise its presence. This case adds to the literature the atypical but life-threatening clinical presentation of VMC.

Von Meyenburg complex and complete ductal plate malformation along with Klatskin tumour: a rare association

Von Meyenburg complexes (VMCs), or bile duct microhamartomas, are among the constellation of defects of ductal plate malformation. These present as multiple small intrahepatic cysts and are diagnosed incidentally. Association of intrahepatic VMCs with a bile duct cancer has rarely been reported. We describe a case of a 53-year-old man presenting with obstructive jaundice. Biochemistry and radiology gave a provisional diagnosis of a resectable Klatskin tumour. The patient underwent right hepatectomy with common bile duct and caudate lobe excision. The histopathological examination demonstrated intrahepatic VMCs with complete ductal malformation and malignancy at the hilum.

A case of solitary bile duct hamartoma with advanced gastric carcinoma: findings in contrast-enhanced ultrasonography

Bile duct hamartomas (BDH), which are also known as von Meyenburg complexes, are benign neoplasms that involve cystic dilatation of the bile duct surrounded by fibrous stroma. However, multiple lesions develop in most cases of BDH, whereas a solitary lesion, as seen in our case, is relatively rare. We report here the co-existence of gastric carcinoma and BDH mimicking metastasis in a 30-year-old woman. A lesion measuring 13 × 9 mm with the appearance of a hyperechoic nodule with no pulsatile blood flow signals was observed on US and Doppler US in S4 of the liver. On contrast-enhanced ultrasonography (CEUS), the septum-like structure in the tumor was weakly enhanced at 17 s after administration of Sonazoid. There has been no description of solitary BDH findings on CEUS in the literature. We present the US findings of BDH, including those yielded by CEUS using Sonazoid, along with the microscopic pathological correlation.

Extra-hepatic bile duct hamartoma in a 10-month-old with a morgagni hernia and multiple anatomical anomalies: a rare and incidental finding

Von Meyenburg complexes (VMCs), also known as bile duct hamartomas, are a part of a group of ductal plate malformations. They are typically present intrahepatically. In this case, we present to our knowledge the first report of an extra-hepatic VMC in the pediatric population. The patient presented as a 10-month-old infant with a weeklong history of progressive breathing difficulty. A chest radiograph was obtained, showing intestinal loops in the thoracic cavity consistent with a Morgagni's hernia, unrelated to his breathing difficulty. The patient then underwent an elective repair of his congenital diaphragmatic defect. During the operation, the bile duct hamartoma was found adherent to the accessory lobe of the liver, present to the left of the ligamentum teres.

Multiple bile duct hamartomas mimicking diffuse hepatic metastasis: GI image

Bile duct hamartomas (von Meyenburg complex) are the rare benign neoplasm of the liver due to dysembryogenesis; constituted historically, cystic dilatations of the bile duct encompassed by fibrous stroma. Usually, they are asymptomatic and are not detected on routine radiological examinations including ultrasound or CT scan. Magnetic resonance cholangiography has been suggested as the best investigation for their imaging diagnosis. Their presence can cause diagnostics confusion and complicate the patient's management. We report a 45-year-old female with symptomatic cholelithiasis, whose liver on laparoscopy mimicked multiple hepatic metastases.

Diagnosis and treatment of benign focal liver lesions

BACKGROUND

With the routine use of improved imaging modalities, more benign liver lesions are detected nowadays. An accurate characterization of these incidental lesions may be a challenge, and frequently a biopsy or even unnecessary surgery is being performed. However, these interventions are not always to the benefit of the patient.

METHODS

A Medline search of studies relevant to imaging diagnosis and management of the most common, benign, solid and non-solid liver lesions was undertaken. References from identified articles were handsearched for further relevant articles. The authors' own experiences with benign liver lesions were also taken into account.

RESULTS

Although atypical imaging features are the exception rather than the rule, it is sometimes difficult to differentiate between benign and malignant lesions, and knowledge of their imaging features is essential if unnecessary work-up is to be avoided. The use of tissue-specific contrast media, which has clearly improved the accuracy of highly advanced radiological techniques, may be helpful during differential diagnosis. Once having established an accurate diagnosis, surgery is rarely indicated for a benign liver lesion because of its asymptomatic nature.

CONCLUSION

Knowledge of imaging features and a clear management strategy during diagnostic work-up, emphasizing the indications for surgery, will minimize the number of patients who have to undergo biopsy or unnecessary surgery.

Resovist-enhanced MRI for preoperative assessment of colorectal hepatic metastases: a case of multiple bile duct hamartomas associated with colon cancer

Extensive preoperative assessment of hepatic metastases is required in colon cancer patients. We report a case in whom the preoperative investigation by ultrasound scan and contrast-enhanced computed tomography revealed numerous cystic lesions of the liver, suspicious of von Meyenburg complex. Magnetic resonance and magnetic resonance cholangiographic images demonstrated typical features of von Meyenburg complex. Further Resovist-enhanced magnetic resonance imaging detected two hemangiomas in addition to the multiple cystic lesions. So-called Kupffer cell imaging strongly helped the detection of these hemangiomas, and a combination of various magnetic resonance pulse sequences was of great value for the differential diagnosis of cystic lesions and hemangiomas. In cases in whom conventional imaging studies fail to give a definite diagnosis, such as in the present case, superparamagnetic iron oxide-enhanced magnetic resonance imaging is meaningful for adequate preoperative staging.

Multiple biliary hamartomas: magnetic resonance features with histopathologic correlation

The purpose of this study was to report the magnetic resonance imaging (MRI) features of multiple biliary hamartoma (MBH) and to correlate them with histopathology. MRI features of 11 patients with MBH proven by histology were retrospectively reviewed and correlated to histopathology. MBH presented as multiple, tiny, and uniformly distributed lesions in all cases. All were hypointense on T1-weighted images and hyperintense on T2-weighted images relative to the liver parenchyma. Mural nodules were identified in 10 of 11 (91%) cases. They were isosignal on T1-weighted images, intermediate signal on T2-weighted images. Gadolinium-enhanced images showed mural nodule enhancement in 9 of 10 patients (90%) or a peripheral rim-like enhancement of the whole lesion in one case (9%). MBH were present in all liver specimens. In the six patients examined at MR cholangiography, the lesions lacked communication with the biliary tree. At histopathology, the mural nodule corresponded to an endocystic polypoid projection made of conjunctive septa. Three (27%) patients had associated focal nodular hyperplasia, and 1 (9%) had concomitant cholangiocarcinoma. MRI features allowed diagnosis of MBH with accuracy. Their recognition, especially the mural nodule, may help avoid misdiagnosis.

Bile duct hamartomas (von Mayenburg complexes) mimicking liver metastases from bile duct cancer: MRC findings

We present a case of a 72-year-old man with a common bile duct cancer, who was initially believed to have multiple liver metastases based on computed tomography findings, and in whom magnetic resonance cholangiography (MRC) revealed a diagnosis of bile duct hamartomas. At exploration for pancreaticoduodenectomy, liver palpation revealed disseminated nodules at the surface of the liver. These nodules showed gray-white nodular lesions of about 0.5 cm in diameter scattered on the surface of both liver lobes, which were looked like multiple liver metastases from bile duct cancer. Frozen section of the liver biopsy disclosed multiple bile ducts with slightly dilated lumens embedded in the collagenous stroma characteristics of multiple bile duct hamartomas (BDHs). Only two reports have described the MRC features of bile duct hamartomas. Of all imaging procedures, MRC provides the most relevant features for the imaging diagnosis of bile duct hamartomas.

Imaging findings of biliary hamartomas (von Meyenburg complexes)

To evaluate the imaging findings of biliary hamartomas (von Meyenburg complexes, vMCs) and discuss their differential diagnosis from other related diseases, imaging findings of biliary hamartomas on ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI), magnetic resonance cholangiopancreatography (MRCP), and hepatobiliary scintigraphy were prospectively analyzed in six patients. On ultrasound images, five of the six cases showed multiple small hyper- and hypoechoic lesions with comet-tail echoes, especially when magnified using the zoom function. In all six cases, multiple tiny hypodense lesions less than 10 mm in diameter were scattered throughout the liver with no enhancement on CT. These tiny lesions were demonstrated to be hyper- and hypointense on T2- and TI-weighted images, respectively, in three patients who underwent MRI examinations. MRCP was performed in two patients, and it clearly showed multiple tiny round and irregular-shaped hyperintense lesions. MRCP and hepatobiliary scintigraphy showed normal appearances of intra- and extrahepatic bile ducts in two and one patients, respectively. Imaging modalities are useful in the diagnosis and differential diagnosis of vMCs. A correct diagnosis might be obtained when typical imaging findings present even without histological confirmation.

Imaging findings of biliary hamartomas

AIM: To evaluate the imaging findings of biliary hamartomas (von Meyenburg complexes, VMCs) and discuss the differential diagnosis with other related diseases.

METHODS: Imaging findings of biliary hamartomas on ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI), MR cholangiopancreatography (MRCP)and hepatobiliary scintigraphy were retrospectively analyzed in six patients.

RESULTS: On ultrasound images, five of the six cases showed multiple small hyper- and hypo-echoic lesions with comet-tail echoes, especially when magnified by US with the usage of zoom function. In all the six cases, multiple tiny hypodense lesions less than 10 mm in diameter were revealed as scattered throughout the liver with no enhancement on CT. These tiny lesions were demonstrated to be hyper- and hypo-intensity on T2- and TI-weighed images, respectively, in three patients who underwent MRI examinations. MRCP was performed in two patients, and clearly showed multiple tiny irregular- and round-shaped hyper-intensity lesions. MRCP and hepatobiliary scintigraphy showed normal appearances of intra- and extra-hepatic bile ducts in two and one patients, respectively.

CONCLUSION: Imaging modalities are useful in the diagnosis and differential diagnosis of VMCs. A correct diagnosis might be obtained when typical imaging findings are present even without a histological confirmation.

Biliary adenofibroma: a rare neoplasm of bile duct origin with an indolent behavior

We report a case of biliary adenofibroma in a 47-year-old woman, who presented with right upper quadrant pain for several months. Abdominal imaging revealed a 16-cm solid and cystic mass in the left hepatic lobe. Histologically, the tumor showed two distinct components: 1) cystic and tubular structures lined by low columnar to cuboidal biliary-type epithelium, and 2) a dense fibrous stroma composed of spindle-shaped cells with only mild nuclear pleomorphism and inconspicuous nucleoli. Mitoses and stromal invasion were absent. The glandular epithelium stained positively for keratin AE.3/Cam 5.2, cytokeratin 7, cytokeratin 19, carcinoembryonic antigen, and epithelial membrane antigen and had a low Ki-67 proliferative index. In addition, the epithelium was positive for D10 but did not stain for 1F6 or acid mucin with alcian blue stain. This staining pattern, similar to bile duct hamartoma (von Meyenburg complex) with which this tumor shares morphologic similarity, suggests that biliary adenofibroma originates from interlobular or larger bile ducts. Three years after a subtotal resection no metastasis or significant tumor growth was noted. However, given the marked nuclear p53 immunoreactivity and tetraploidy status observed in this tumor, we cannot exclude that biliary adenofibroma may represent a premalignant process that warrants complete resection and thorough histopathologic examination.

Hepatic bile duct hamartomas (von Meyenburg Complexes): MR and MR cholangiography findings

Multiple bile duct hamartomas (MBDHs) of the liver, also known as von Meyenburg complexes, are easily confused with diffuse metastatic disease of the liver on US and CT. At present, histologic examination after tissue preevaluation is usually necessary for definite diagnosis. We report four cases in which the MR features, and especially the MR cholangiographic (MRC) findings, were highly suggestive for MBDH. Characteristic findings include multiple markedly hyperintense nodules on T2-weighted imaging, typically measuring <1.5 cm; no communication with the biliary tree; and irregular delineation of the lesions with no or slight rim enhancement following gadolinium administration.

Cystic focal liver lesions in the adult: differential CT and MR imaging features

Cystic lesions of the liver in the adult can be classified as developmental, neoplastic, inflammatory, or miscellaneous. Although in some cases it is difficult to distinguish these entities with imaging criteria alone, certain cystic focal liver lesions have classic computed tomographic (CT) and magnetic resonance (MR) imaging features, which are important for the radiologist to understand and recognize. Lesions with such features include simple (bile duct) cyst, autosomal dominant polycystic liver disease, biliary hamartoma, Caroli disease, undifferentiated (embryonal) sarcoma, biliary cystadenoma and cystadenocarcinoma, cystic subtypes of primary liver neoplasms, cystic metastases, pyogenic and amebic abscesses, intrahepatic hydatid cyst, extrapancreatic pseudocyst, and intrahepatic hematoma and biloma. Specific CT and MR imaging findings that are important to recognize are the size of the lesion; the presence and thickness of a wall; the presence of septa, calcifications, or internal nodules; the enhancement pattern; the MR cholangiographic appearance; and the signal intensity spectrum. In addition, access to critical clinical information remains extremely important. The most important clinical parameters defined include age and gender, clinical history, and symptoms. An understanding of the classic CT and MR imaging appearances of cystic focal liver lesions will allow more definitive diagnosis and shorten the diagnostic work-up.