Benign focal liver lesions masquerading as primary liver cancers on MRI.

Hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC) are the most common primary liver malignancies. HCC and ICC have characteristic imaging findings, but a number of benign entities can appear similar and can cause diagnostic dilemma. Ideally, accurate and timely diagnosis of these conditions can help the patient to avoid a needle biopsy or even unnecessary treatment. In this article, we present various benign liver lesions that display imaging characteristics that are similar to HCC and ICC on magnetic resonance imaging (MRI) and discuss salient features that may assist in accurate diagnosis.

Bile duct adenoma: imaging features and radiologic-pathologic correlation.

PURPOSE: This study aimed to reveal characteristic imaging features of bile duct adenoma (BDA) by radiologic-pathologic correlation. MATERIALS AND METHODS: We retrospectively analyzed pathological and imaging findings of seven patients with BDA. RESULTS: The median maximum diameter of BDA was 5.5 mm. Six lesions had hemispheric morphology. Seven lesions were located in the liver subcapsular region, and proliferation of bile ductules without atypia and fibrous stroma was observed. Two lesions had different microscopic findings. In both lesions, proliferation of bile ductules without atypia was observed in the margin. In one lesion, the percentage of fibrosis and hyalinization was higher at the center than at the margin. In the other lesion, inflammatory cell infiltration was observed in the center. On contrast-enhanced imaging, BDAs showed hypervascularity in the early phase and prolonged enhancement in the delayed phase. On contrast-enhanced multidetector computed tomography during hepatic arteriography, two lesions showed ring-like enhancement in the first phase and prolonged enhancement in the second phase. These were the different histopathologic features of BDAs between the margin and center. CONCLUSION: Bile duct adenoma can be characterized as a small semicircular lesion located in the liver subcapsular region, which show hypervascularity in the early phase with prolonged enhancement.

Imaging features of bile duct adenoma: case series and review of literature.

PURPOSE: We aimed to evaluate the imaging features of bile duct adenoma (BDA) on ultrasonography (US), computed tomography (CT), and magnetic resonance imaging (MRI). METHODS: Retrospective search in our institution database was performed for histologically confirmed BDA. Their imaging studies before histologic confirmation were reviewed. The search identified seven adults (mean age, 52.9 years) with histologically proven single BDA each. US (n=3), CT (n=5), and MRI (n=3) were performed before histologic confirmation. Additionally, a systematic English literature review for BDA and reported imaging findings since 2000 was also conducted using the following search criteria "bile duct adenoma, peribiliary hamartoma, biliary adenoma, CT, ultrasound, MRI" (date range: 01/01/2000 through 08/31/2016). The imaging findings of those cases reported were summarized and compared with our series. RESULTS: All seven individual nodules were well circumscribed. Five lesions were located in the right hepatic lobe and two in the left hepatic lobe. On US, lesions appeared hypoechoic (n=2) and hyperechoic (n=1). BDA was hypodense on unenhanced CT images (n=1). On MRI, BDA were hypointense on T1 (n=3), hyperintense on T2 (n=3), and hyperintense on diffusion-weighted images (n=2). On contrast-enhanced CT and MRI, BDAs showed arterial phase hyperenhancement that persisted on portal venous/delayed phase images. CONCLUSION: BDA demonstrates characteristic arterial phase hyperenhancement that persisted into the portal venous and delayed phases on CT and MRI, which may be useful in differentiating from other hepatic lesions.

Imaging diagnosis-cholangiocellular adenoma: contrast-enhanced ultrasonographic findings of a benign tumor mimicking malignant neoplasia in a dog.

A 9-year-old Giant Schnauzer was referred for polyuria and polydipsia. On abdominal ultrasound, a hyperechoic mass with low color Doppler signal was detected in the medial right hepatic lobe. Contrast-enhanced ultrasound (CEUS) demonstrated increased enhancement of the mass during the arterial phase, and contrast washout during portal and late phases with decreased enhancement relative to the liver. These findings were consistent with primary liver malignancy or liver metastasis. A final diagnosis of cholangiocellular adenoma was made based on histopathology. To our knowledge, this is the first description of a benign hepatic neoplasm exhibiting malignant CEUS characteristics in a dog.

A benign tumour of the liver mimicking malignant liver disease--cholangiocellular adenoma.

OBJECTIVE: To describe three patients with liver lesions mimicking malignant tumours diagnosed finally, using contrast-enhanced ultrasound, as cholangiocellular adenoma (bile duct adenoma). MATERIAL AND METHODS: Focal liver lesions found incidentally in three patients. Contrast-enhanced ultrasound was with use of Siemens or Esaote equipment, low MI technique, after an intravenous bolus of 2.4 ml Sonovue (Bracco, Italy). RESULTS: Lesions were 9 mm, 15 mm and 20 mm in diameter and all were enhanced in the arterial phase and hypo-enhanced in the portal venous and late phases, suggesting their malignant nature. In two patients, no primary liver tumour was found, and in the third patient, previously resected for breast cancer, a tissue specimen was considered useful for characterizing tumour receptors for more targeted chemotherapy, the lesion being assumed metastatic in nature. Transcutaneous core biopsies were performed in all three patients. Pathological analysis (including the reference pathology) revealed cholangiocellular adenoma in all of them. CONCLUSION: Cholangiocellular adenoma is a rare entity and can be a reason for possible false malignant diagnosis using contrast-enhanced ultrasound. Follow-up examinations are recommended.

Assessment of a biliary hamartoma with contrast-enhanced sonography using two different contrast agents.

A 49 year old male with carcinoma of the esophagus was staged using conventional US of the abdomen. US revealed signs of cirrhosis and a hyporeflexive focal liver lesion of about 5 mm in diameter was found. Low-MI contrast-enhanced ultrasound (CEUS) with SonoVue (Bracco, Milano, Italy) showed an enhancement pattern which was typical for benign liver lesions while high-MI CEUS with Levovist (Schering, Berlin, Germany) revealed a contrast defect in the liver late phase (4:30 min p. i.) which is typical for a malignant lesion. Due to these findings the lesion was evaluated as a potentially malignant lesion and a biopsy was performed. Histology showed a benign biliary hamartoma and incomplete cirrhosis. The findings confirmed that liver-specific contrast agents have the ability to detect very small focal liver lesions not derived from hepatic tissue but may lead to a misinterpretation as a malignant lesion. Nevertheless biliary duct adenomas are benign lesions with almost the same perfusion properties as normal liver parenchyma. Therefore, while using SonoVue, such a misinterpretation of these very common but in most cases very small and not detectable lesions seems unlikely.

Magnetic resonance findings of bile duct adenoma with calcification.

Computed tomographic (CT) and magnetic resonance (MR) appearances of bile duct adenoma (BDA in a patient who underwent partial hepatectomy of segment 8 are presented. BDA showed a ring-shaped hyperdense area suggesting calcification and ring enhancement on CT. It appeared hypointense on both T1- and T2-weighted MR images. Preoperatively, the diagnoses considered included metastatic carcinoma, cholangiocarcinoma, tuberculosis, and rare tumors such as epithelioid hemangioendothelioma. The radiological findings were confirmed by pathological investigation.

[Hepatobiliary cystoadenomas]. / Cistoadenomas hepatobiliares.

Cystoadenomas of the liver are rare cystic tumors that have seldom been reported. Accurate preoperative diagnosis is difficult because they are usually mistaken for more frequent lesions. Due to their malignant potential, complete surgical removal of the lesion is required. Correct diagnosis is guided by clinical history, radiological imaging, and laboratory parameters. We report two of these rare cases and discuss the spectrum of presentation, pathological features and treatment of these tumors.

Cytological diagnosis of cholangiocarcinoma with rib metastasis in a young female--a case report.

Intrahepatic cholangiocarcinomas are second most common primary tumors of the liver. They are usually seen in 6th to 7th decades of life and at an advanced stage leading to poor prognosis. Their occurrence in the young age group is rare. Histopathological features of this tumor are well documented but literature regarding cytomorphological features on FNA is limited. We describe the cytological features of this tumor in a young woman presenting primarily with a rib metastasis. FNA smears from hard lump in the right chest wall and liver mass showed small round tumor cells arranged in the form of sheets, clusters and occasional tubules. The cells showed mild pleomorphism and bland nuclear morphology. Intimately admixed with tumor cells were spindle shaped fibroblastic cells. Serum alpha-fetoprotein level was within normal limit. Special stain for bile and immunocytochemical staining for NSE, chromogranin and CALLA were all negative. Cholangiocarcinoma was diagnosed based on cytological findings and special stains and this diagnosis was histologically confirmed on biopsy.

Huge biliary cystadenoma mimicking cholecystic lymphangioma in subhepatic space.

Biliary cystadenoma is a rare cystic neoplasm and constitutes only 5% of all intrahepatic cysts of biliary origin. We report a case of a 44-year-old woman with huge biliary cystadenoma in the subhepatic space, mimicking a cholecystic lymphangioma. Findings of various imaging modalities including reconstructed CT image are presented and correlated with surgical and pathologic findings.

Clinical and radiological features of biliary papillomatosis.

Biliary papillomatosis is a rare disease with strong potential for malignant degeneration. Diagnosis is often not easy and most are made intraoperatively. In the present study, five patients with biliary papillomatosis admitted between 1990 and 1997 were reviewed. Their clinical presentation, radiological and biochemical findings were analysed. The aim of the study was to discern a set of characteristic features that would enable an early diagnosis. All of the five patients presented with recurrent episodes of acute cholangitis and epigastric pain with raised serum alkaline phosphatase. Imaging modalities including ultrasound, CT, endoscopic retrograde cholangio-pancreatogram, MRI and magnetic resonance cholangio-pancreatogram were reviewed. Salient imaging features included a dilated biliary tree with multiple ill-defined and fuzzy filling defects or endoluminal frond-like mass lesions. In conclusion, biliary papillomatosis is a rare but important cause of biliary obstruction with relapsing cholangitis and obstructive jaundice. With a healthy index of suspicion, the diagnosis can be reached when the above features are available.

Ultrasonographic evaluation of biliary cystadenomas in cats.

The purpose of this study was to describe the ultrasonographic appearance of biliary cystadenomas in cats and compare the findings to a similar rare form of liver tumor in humans. Biliary cystadenomas are uncommon, benign liver tumors of older cats that may occur as focal or multifocal cystic lesions within the liver. The records of 10 cats which had abdominal ultrasonography and histologic diagnosis of biliary cystadenoma were reviewed. The average age of affected cats was 13.3 years (range 10-16 years). Eight cats were neutered males and two were neutered females. In three cats, the tumors were not seen ultrasonographically due to their small size or from being obscured by near-field reverberation echoes. The remaining seven cats had solitary (4 cats) or multifocal (3 cats) masses corresponding to variable ultrasonographic patterns: multilocular masses containing thin-walled cysts, hyperechoic masses with cystic components, or masses of mixed echogenicity with cystic components. The masses had variable ultrasonographic patterns when multifocal disease was present. Recognizable cysts were evident somewhere within the tumors seen ultrasonographically, although sometimes the cysts appeared very small. The biliary cystadenomas were thought to be clinically silent. Although liver enlargement or a cranial abdominal mass was palpable in 4 cats, no consistent trend of clinical signs, CBC or serum biochemical abnormalities could be directly attributed to biliary cystadenoma. The treatment of choice is surgical resection of the tumor, as continued growth may compress adjacent vital structures within the liver. The differential diagnosis of biliary cystadenomas from other cystic liver lesions such as hepatic cysts, hematomas, abscesses, parasitic cysts, or other liver tumors is discussed.

Papillary adenoma of the distal common bile duct.

A 73-year-old man with a papillary adenoma located in the distal common bile duct is reported. He underwent pylorus-preserving pancreatoduodenectomy. The lesion in the common bile duct featured papillary proliferation of the epithelium and fibrous elements with diffuse infiltration by inflammatory cells. Positive staining for MIB-1 (Ki-67) and p53 was identified in the nuclei of the proliferative epithelium. These findings suggested the malignant potential of this lesion. Further progress in imaging diagnostic techniques should increase the frequency with which such lesions are discovered. Even now, if mural irregularities and defects are found in the extrahepatic biliary system, especially the distal common bile duct, the possibility of such borderline biliary adenoma should be taken into consideration when making a diagnosis.

Hepatobiliary cystadenoma can protrude and grow into the bile ducts.

BACKGROUND/AIMS: To evaluate the phenomenon and the potential reasons for protrusion and growth of hepatobiliary cystadenoma into the extrahepatic bile ducts in our patients, accomplished by a review of the data regarding hepatobiliary cystadenomas published elsewhere. METHODOLOGY: In a retrospective open study conducted over the last eight years, five patients with hepatobiliary cystadenoma and one patient with hepatobiliary cystadenocarcinoma were operated on. All the patients were females aged between 25 to 61 years. Diagnostic procedures, laboratory, operative and histopathological findings and treatment were evaluated. RESULTS: Most of our patients were found to have hepatobiliary cystadenoma located in the left surgical liver. In three out of five patients with HBC mesenchymal stroma was histologically detected. In two of the three, protrusion and growth into the extrahepatic bile ducts was found. CONCLUSION: Considering the pathogenesis, location and the morphology of HBC, the mesenchymal stroma may present the competent potential for intraductal progression of the tumor. Radical excision should be performed for successful treatment of hepatobiliary cystadenomas, because of the potential for reoccurrence.

Laser therapy for multiple biliary papillomatosis via choledochoscopy.

BACKGROUND: Multiple biliary papillomatosis is a rare tumour of the biliary tract but is capable of multicentric malignant transformation. The complete removal of these tumours is difficult because it involves a field change of the biliary tract. METHODS: Exploration with choledochoscopy is a prerequisite for thorough assessment of the extent of involvement. Incorporation of laser ablation via a laser-delivering fibre with choledochoscopy permits complete removal of the tumour. RESULTS: Repeated laser therapy via choledochoscopy through the T-tube tract enables complete ablation of the tumour which changes the outlook of the prognosis. This is confirmed on subsequent cholangiography. CONCLUSIONS: Laser therapy via choledochoscopy is a satisfactory mode of treatment for multiple biliary papillomatosis. It enables complete and precise ablation of the tumour which certainly changes the prognosis of this condition.