A case of biliary adenofibroma with malignant transformation

Tubulocystic Carcinoma of Bile Ducts: A Distinct Type of Cholangiocarcinoma Associated With Adenofibroma-type Lesions

A type of cholangiocarcinoma (CCA) characterized by peculiar histologic patterns and underlying adenofibromatous lesions has been reported in the literature mostly as individual case reports. This study aims to further clarify the defining characteristics of this spectrum of lesions. Clinicopathologic analysis of 8 biliary tumors with tubulocystic architecture arising in the background of adenofibroma-type lesions was performed. Three of these were also investigated with next-generation sequencing with a 174 genes panel. The patients were 5 males and 3 females, with a mean age of 64.6. All tumors were intrahepatic except for one perihilar that protruded into soft tissues. The mean size was 4.4 cm. At histology, all cases showed a peculiar and cytologically bland tubulocystic pattern that closely resembled tubulocystic-type kidney cancers, including back-to-back microcystic units that formed relatively demarcated nodules, and occurring in the background of adenofibromatous lesions. One case showed perineural invasion by otherwise deceptively benign-appearing microcystic structures, one had areas transitioning to intraductal tubulopapillary neoplasm, and 3 cases harbored more conventional small-duct CCA foci. In those 3 cases, both the tubulocystic and conventional CCA components were investigated by next-generation sequencing separately, and they shared the molecular alterations, including recurrent mutations in chromatin remodeling genes, such as ARID1A , BAP1 , and PBRM1 , and the actionable FGFR2-MCU fusion gene. In the limited follow-up, all but one were alive and free of disease after surgical resection. In conclusion, we described a distinct entity of CCA with specific histo-molecular features, for which we propose the designation of tubulocystic carcinoma of bile ducts.

Biliary adenofibroma: a precursor lesion of intrahepatic cholangiocarcinoma

Biliary adenofibroma (BAF) is an uncommon liver tumor with a high propensity for malignant transformation. The histomorphology of BAF with malignant transformation can show a spectrum of changes ranging from benign, dysplastic to frank malignancy. Thus, the diagnosis of BAF imposes the pursuit of dysplasia/ malignancy focus. We presented a case of intrahepatic cholangiocarcinoma arising from BAF in a 49-year-old woman with detailed histomorphology. We also performed a PubMed database search and tabulated all previously reported cases of BAF with dysplasia/ malignant transformation. A statistic comparison of age, sex ratio, size of the tumor, and survival following complete resection between BAFs with and without dysplasia/ malignancy from the retrieved data is presented. Our analysis did not highlight any statistically significant difference between BAFs with and without dysplasia/ malignancy in age, sex ratio, tumor size, and survival following complete surgical resection. Our study highlights the histopathology and immunohistochemistry of a case of BAF with malignant transformation and highlights the importance of this diagnosis in management. Further longitudinal studies on a larger cohort of patients are required to validate our findings.

Multimodal imaging findings of intrahepatic cholangiocarcinoma arising from a biliary adenofibroma: a case report with radiological-pathological correlation

PURPOSE

Biliary adenofibroma is a solid microcystic epithelial neoplasm in the liver, comprising microcystic and tubuloacinar glandular tissues lined by a non-mucin secreting biliary epithelium and supported by a fibrous stroma. It is an extremely rare benign tumor with potential for malignant transformation. Herein, we report the case of a 64-year-old woman diagnosed with intrahepatic cholangiocarcinoma arising from biliary adenofibroma.

METHODS

Imaging studies revealed a tumor of 50 mm diameter, consisting of two components in S1 of the liver. The ventral portion of the tumor showed an ill-defined mass with early peripheral and gradual centripetal enhancement invading to the middle hepatic vein on computed tomography (CT), diffusion restriction on magnetic resonance images, and high fluorine-18-2-deoxy-D-glucose (FDG) uptake on positron emission tomography, like conventional intrahepatic cholangiocarcinoma. The dorsal portion showed a well-defined and low-attenuated mass with heterogeneous early enhancement and partial wash-out on CT, marked hyperintensity on heavily T2-weighted images, and low FDG uptake. The patient subsequently underwent extended left hepatectomy.

RESULTS

Pathologically, the former was diagnosed as cholangiocarcinoma and the latter as biliary adenofibroma. We discuss the radiological-pathological correlation of the tumor with a literature review.

CONCLUSION

Preoperative diagnosis of biliary adenofibroma is extremely challenging; however, clinically, it is crucial not to miss the presence of malignant findings.

Intrahepatic cholangiocarcinoma: typical features, uncommon variants, and controversial related entities

Pathologists play a central role in the diagnosis and classification of intrahepatic cholangiocarcinoma (iCCA). iCCA is currently classified into small- and large-duct types. Small-duct iCCA is characterized by a mass-forming gross appearance, mucus-poor ductule-like histology, and frequent association with chronic parenchymal liver diseases (eg, cirrhosis). Large-duct iCCA is an infiltrative duct-forming adenocarcinoma with a fibrotic stroma, similar to perihilar cholangiocarcinoma. Chronic cholangiopathies (eg, primary sclerosing cholangitis, liver flukes) are associated with an increased risk of large-duct iCCA. Alterations in IDH1/2, BAP1, or FGFR2 are characteristic molecular features of small-duct iCCA, whereas mutations in KRAS and SMAD4 and the amplification of MDM2 are mainly observed in large-duct iCCA. C-reactive protein and N-cadherin are commonly expressed in small-duct iCCA, and S100P is a good marker for large-duct iCCA. In addition to well-known subtypes (eg, cholangiolocellular carcinoma), uncommon variants are recognized. A tubulocystic variant is often misinterpreted as a benign neoplasm. Mucoepidermoid and enteroblastic variants are under-recognized and pose a diagnostic challenge. Cholangioblastic cholangiocarcinoma characterized by inhibin-A expression was recently found to have an NIPBL-NACC1 gene fusion. Despite significant advances in hepatobiliary pathology, there are still controversial premalignant entities that require large comprehensive studies. There are morphological overlaps between biliary adenofibroma and the tubulocystic variant of iCCA. Type 2 intraductal papillary neoplasm of the bile duct (IPNB) is typically associated with invasive malignancy at the initial presentation and lacks unique molecular features. Therefore, some pathologists prefer the term "papillary cholangiocarcinoma" over type 2 IPNB.

Malignant transformation of biliary adenofibroma combined with benign lymphadenopathy mimicking advanced liver carcinoma: A case report

BACKGROUND

Biliary adenofibromas (BAFs) are rare primary hepatic neoplasms, some of which can potentially undergo malignant transformation. Here, we describe a rare case of malignant transformation of BAF.

CASE SUMMARY

A 51-year-old female was referred to our hospital with epigastric pain. Computed tomography showed a solitary liver mass combined with the enlargement of multiple mediastinal and cervical lymph nodes, clinically mimicking a liver carcinoma with extensive lymph node metastasis. However, core needle biopsy suggested BAF with malignant transformation. Finally, the patient underwent curative resection of the neoplasm and was recurrence-free for 12 mo.

CONCLUSION

Our case serves as an example of a rare manifestation of BAF. Our report and the previously published experience, reinforce that curative resection should be considered the primary treatment for BAFs with malignant transformation, leading to a favorable prognosis.

Imaging features of biliary adenofibroma of the liver with malignant transformation: a case report with literature review

Background

Biliary adenofibroma (BAF) is a rare primary hepatic tumor with the potential risk of malignant transformation. Given the extreme rarity of the disease, the imaging features of BAF are unclear. We presented a case of malignant BAF and conducted a systematic literature review. We highlighted the key imaging features in the diagnosis and aggressiveness assessment of BAF, as well as the role of various imaging modalities in evaluating BAF.

Case presentation

We reported a 64-year-old woman with a 5-months history of pain in the right upper quadrant abdomen. US of the liver showed a hypoechoic subcapsular nodule. CT scan revealed a subcapsular solid-cystic mass in segment V of the liver. The mass showed a marked enhancement in the arterial phase followed by wash-out in the venous phase. The patient underwent partial resection of liver’s right lobe. The mass was diagnosed as BAF with malignant transformation by postoperative pathology.

Conclusions

CT and MRI are helpful in recognizing and characterizing BAF. The imaging features of BAF include a solitary, large solid-cystic mass with a well-defined margin, lobulated shape, and internal septa; subcapsular location; no intrahepatic bile duct communication; the presence of von Meyenberg complexes in background liver. The enhancement patterns may have the potential to assess the aggressiveness of BAF, and that marked enhancement in the arterial phase followed by wash-out in the venous phase is suggestive of malignant BAF.

Pathological, molecular, and clinical characteristics of cholangiocarcinoma: A comprehensive review

Cholangiocarcinomas are a heterogeneous group of highly aggressive cancers that may arise anywhere within the biliary tree. There is a wide geographical variation with regards to its incidence, and risk-factor associations which may include liver fluke infection, primary sclerosing cholangitis, and hepatolithiasis amongst others. These tumours are classified into intrahepatic, perihilar and distal based on their anatomical location. Morphologically, intrahepatic cholangiocarcinomas are further sub-classified into small and large duct variants. Perihilar and distal cholangiocarcinomas are usually mucin-producing tubular adenocarcinomas. Cholangiocarcinomas develop through a multistep carcinogenesis and are preceded by dysplastic and in situ lesions. While clinical characteristics and management of these tumours have been extensively elucidated in literature, their ultra-structure and tumour biology remain relatively unknown. This review focuses on the current knowledge of pathological characteristics, molecular alterations of cholangiocarcinoma, and its precursor lesions (including biliary intraepithelial neoplasia, intraductal papillary neoplasms of the bile duct, intraductal tubulopapillary neoplasms and mucinous cystic neoplasm).

Biliary Adenofibroma: A Rare Liver Tumor with Transition to Invasive Carcinoma

Biliary adenofibroma is a rare benign liver tumor with potential for malignant transition. It has a bile duct origin characterized by a complex tubulocystic biliary epithelium with fibrous stroma. MRI features may suggest this uncommon entity, and histological findings can be diagnostic. We report a case of biliary adenofibroma with transformation to an intrahepatic cholangiocarcinoma.

Imaging presentation of biliary adenofibroma: A case report

BACKGROUND

Biliary adenofibroma (BF) is a rare benign epithelial tumor with the possibility of malignant transformation. Its main pathological feature is a well-defined cystic or honeycomb mass. BF has no specific clinical manifestations or laboratory and imaging findings; thus, it is easily misdiagnosed before surgery. This report describes a case in which biliary cystadenoma was misdiagnosed preoperatively and BF was diagnosed postoperatively. The imaging features, particularly the magnetic resonance imaging (MRI) features, were analyzed and summarized.

CASE SUMMARY

A 68-year-old Chinese man was admitted to our hospital with a 2-mo history of abdominal discomfort. Following admission to our hospital, laboratory examinations showed normal tumor marker concentrations and liver function. Hepatocellular carcinoma was considered after contrast-enhanced ultrasound examination. MRI suggested the possibility of cystadenoma of the bile duct. However, postoperative pathological examination confirmed the diagnosis of BF. No local recurrence was found 1 mo after surgery.

CONCLUSION

Our objective is to highlight the imaging diagnostic value of BF, especially on an MRI enhanced scan with gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid.

Robotic enucleation of a biliary adenofibroma

A 69-year-old man was referred to the hepatobiliary surgeons for mild enlargement of an asymptomatic cystic liver lesion found on routine screening in 2017 that measured 3.7×3.6×4.3 cm. Work-up with MRI revealed a complex multilocular cyst that had enlarged to 6.6×5.5×4.6 cm. Other work-up was unremarkable. He had a Eastern Cooperative Oncology Group score of 1; therefore, a surgical excision was planned due to the possibility for malignancy. A robotic approach with enucleation of the lesion was undertaken, with plans for return for a wider resection if pathological examination revealed malignancy. The lesion was noted to be a biliary adenofibroma, an exceptionally rare lesion that is thought to be benign, but requires excision due to potential malignant degeneration. The patient was discharged home the following day and has had minimal pain in his postoperative course.

Benign biliary neoplasms and biliary tumor precursors

Benign biliary tumor are common lesions that are often an incidental finding in subjects who undergo medical imaging tests for other conditions. Most are true neoplasms while few result from reactive or malformative proliferation. Benign tumors have no clinical consequences, although the premalignant nature or potential for malignant transformation is of concern in some cases. The main practical problem for pathologists is the need to differentiate them from malignant biliary tumours, which is not always straightforward.

Premalignant lesions of the bile duct have been described, although their incidence has been poorly characterized. These lesions include biliary mucinous cystic neoplasms, intraductal papillary neoplasms of the bile duct, and biliary intraepithelial neoplasia. In this article, histopathology of benign biliary tumors and biliary tumor precursors is discussed, with a focus on the main diagnostic criteria.

Magnetic Resonance Imaging Findings of Biliary Adenofibroma

Biliary adenofibroma is a rare tumor with a bile duct origin characterized by a complex tubulocystic non-mucin secreting biliary epithelium with abundant fibrous stroma. The MRI features of biliary adenofibroma are not well established. The authors encountered two patients with biliary adenofibroma and reviewed the literature focusing on the MRI findings. A well-circumscribed multicystic tumor with septal enhancement and no intrahepatic bile duct communication may be the characteristic MRI findings of biliary adenofibroma.

A case of biliary adenofibroma of the liver with malignant transformation: a morphomolecular case report and review of the literature

Background

Biliary adenofibroma is an exceptionally rare benign liver tumor with the potential for malignant transformation. In literature, only 21 cases have been described.

Clinical presentation

In a healthy 63-year-old woman, a partly solid, partly cystic mass in the left lobe of the liver during a routine ultrasound examination was found. The computed tomography (CT) scan of the abdomen showed a 6.3 × 5.0-cm multilobulated cystic, partly hypervascularized mass in the liver segment IVa, with extension into segments II and IVb. There was no evidence of lymph node or distant metastases. Extirpation of the tumor was indicated by the multidisciplinary tumorboard. Microscopic examination showed a biphasic composed tumor with tubules embedded in fibrous stroma. In addition, there were also areas with pseudopapillary projections, as well as parts with focal cribriform-like growth pattern, which have been indicated as a possible sign of malignant transformation. Additionally, we found two different polymorphisms in the encoded TP53 und KIT in both distinct morphology tumor areas by molecular analysis, which ensured a tumor in malignant transformation. The patient has been alive for 24 months after R0 resection without tumor recurrence. Further investigation of more cases of this rare entity is necessary to proof molecular genesis.

Conclusions

We report a rare case of a biliary adenofibroma with transition to an intrahepatic cholangiocellular carcinoma and present a brief literature review.

Double Trouble: A Rare Case of Concurrent Biliary Adenofibroma and Hepatobiliary Mucinous Cystic Neoplasm

Biliary adenofibroma and hepatobiliary mucinous cystic neoplasm are exceedingly rare tumors. To our knowledge, no case of co-existent biliary adenofibroma and mucinous cystic neoplasm has been previously reported. We present a patient who was diagnosed with both tumors concurrently. Both can present with abdominal pain, although some are diagnosed incidentally in asymptomatic patients. Imaging and tumor markers can be suggestive, but histologic examination is needed for definitive diagnosis. Both have a propensity for malignant transformation, thus complete surgical resection is the treatment of choice. Although rare, awareness of these tumors leads to earlier diagnosis and treatment.

Malignant Transformation Arising Within Unusual and Rare Hepatic Lesions: Fibropolycystic Disease Form of Ductal Plate Malformation and Biliary Adenofibroma

Cholangiocarcinoma is the second most common hepatobiliary cancer following hepatocellular carcinoma, and 20% to 25% are intrahepatic. We describe 2 cases of intrahepatic cholangiocarcinoma arising within unusual and rare hepatic lesions, fibropolycystic liver disease form of ductal plate malformation and biliary adenofibroma, whose association with malignancy is rarely reported in the literature.

Biliary Adenofibroma of Liver: Morphology, Tumor Genetics, and Outcomes in 6 Cases

Biliary adenofibroma is a rare primary hepatic neoplasm, recognized in the World Health Organization classification, although only 14 cases have been reported to date. This series includes extended follow-up from 2 of the early case reports and 4 novel cases. Clinical history and histology were reviewed in all 6 cases. Tumor DNA was analyzed for point mutations by multiplex polymerase chain reaction and copy number alterations by array comparative genomic hybridization. The patients included 4 females and 2 males presenting between 46 and 83 years of age, with tumors ranging from 7 to 16 cm in diameter. The tumors had similar morphology, with tubules and cysts lined mainly by bland to mildly atypical cuboidal epithelium embedded in fibrous stroma. Multiplex polymerase chain reaction did not identify mutations in 4 tumors tested. Three tumors tested by array comparative genomic hybridization showed chromosomal copy number alterations, including 1 with amplifications of CCND1 and ERBB2. Three patients underwent resection with no recurrence at 21, 20, and 3 years of follow-up. One patient is alive after 14 months with no resection. Two patients with margin-positive resections had local recurrence at 1 and 6 years after surgery. No patient had distant metastasis. The distinct morphology and multiple clonal cytogenetic alterations in biliary adenofibromas indicate that the lesions are neoplastic. Amplifications of CCND1 and ERBB2 are not typical of benign neoplasms, and suggest that these tumors may have the ability to behave aggressively. However, the clinical outcomes in these patients suggest the neoplasms are only slowly progressive.

Malignant transformation of biliary adenofibroma: a rare biliary cystic tumor

Biliary adenofibromas (BAFs) are rare, benign biliary cystic tumors with potential for malignant transformation. Of the eleven prior cases of BAF reported in the literature, six showed evidence of malignant transformation. We describe the clinical, imaging and pathology features of two cases of malignant BAF and review the existing literature to raise awareness of this entity and provide additional tools for diagnosing this rare tumor Additionally, we identified a loss of function mutation in the cyclin-dependent kinase inhibitor 2A (CDKN2A) tumor suppressor gene in a malignant caudate lobe BAF, thereby providing potential insight into the molecular pathogenesis of BAF malignant transformation. Although additional cases and longer-term follow-up are needed, our cases suggest that recurrence or metastasis of malignant BAF is not common and that complete surgical resection can be curative.