Long-term observation and treatment of a widespread intraductal papillary neoplasm of the bile duct extending from the intrapancreatic bile duct to the bilateral intrahepatic bile duct: A case report

To develop a classification system which helps differentiate cystic intraductal papillary neoplasm of the bile duct from mucinous cystic neoplasm of the liver

OBJECTIVE

To establish a classification system which differentiates cystic intraductal papillary neoplasm of the bile duct (cystic IPNB) from hepatic mucinous cystic tumors (MCN) based on their radiological difference.

METHODS

A total of 75 patients pathologically diagnosed as MCN and IPNB in two major hospitals from 2015 to 2024 were enrolled. Radiological features were recorded and compared between these two tumors. Variables with significant differences were included in multivariate logistic regression (LR) analysis. A decision model was built and simplified based on importance ranking of variables. K-nearest-neighbor (KNN) model was introduced to learn distribution of individuals in main dimensions based on multiple correspondence analysis (MCA) and predicted diagnosis. The diagnostic efficacy of the classification system and the KNN model was compared.

RESULTS

Significant differences existed in Dmax-IVC angle, septation, mural nodule, upstream and downstream biliary dilatation, communication with bile duct between MCN and cystic IPNB. Downstream biliary dilatation and communication with bile duct were highly specific for IPNB (specificity, 97.9 % and 100 %, respectively), which could independently diagnose IPNB. Among four significant indicators in LR analysis, upstream biliary dilatation and Dmax-IVC angle were used for a simplified decision model to attain good applicability. The KNN model based on MCA data achieved highest accuracy (0.910) when K = 11. Overall, the classification system achieved an AUC of 0.882 (0.95CI: 0.797-0.966), compared with 0.911 (0.95CI: 0.818-1.000) in the KNN model, which demonstrated no significant difference (p = 0.655) in differential performance.

CONCLUSION

The classification system combining four important indicators had equivalent performance to KNN model in discrimination, which was simple and applicable for clinical practice, and also accessible on unenhanced examinations.

Magnetic resonance imaging features of bile duct adenoma

Objectives

To evaluate the magnetic resonance imaging (MRI) features of bile duct adenoma.

Methods

The data of 28 patients [with 32 pathologically confirmed bile duct adenomas, including 15 with malignant change (malignant group) and 17 without malignant change (benign adenoma group)] were retrospectively reviewed. Abdominal MRI was performed for all patients; in addition, dynamic enhanced MRI was performed for 18 lesions. The MRI features, including lesion location, maximum size, morphology, signal characteristics, enhancement type, and appearance of the bile duct, were assessed by two abdominal radiologists. Apparent diffusion coefficient (ADC) values were measured and compared.

Results

Of the 32 bile duct adenomas, 22 (68.75%) involved the common bile duct (CBD). While 14/32 (43.75%) lesions presented as focal eccentric-type masses, 9/32 (28.13%) presented as plaque-like masses, 4/32 (12.50%) as bile duct casting masses, and 5/32 (15.62%) as infiltrative masses. A frond-like superficial appearance was seen in 8/32 (25%) lesions. Infiltrative masses were significantly more common in the malignant group than in the benign adenoma group (P = 0.015). While 23/32 (71.88%) lesions were isointense on T1-weighted imaging (T1WI), 24/32 (75%) were hyperintense on T2-weighted imaging (T2WI). Bile duct dilatation was present upstream of the lesion in all cases. Bile duct dilatation at the lesion was seen in 24/32 (75%) cases and downstream of the lesion in 6/32 (18.75%) cases. Of the 18 lesions that underwent dynamic enhanced MRI, 14 (77.78%) showed moderate enhancement and 13 (72.22%) showed persistent enhancement. On diffusion-weighted imaging (DWI), 27/32 (84.37%) lesions showed hyperintensity. Mean ADC value was comparable between the malignant group and the benign adenoma group (P = 0.156).

Conclusions

Bile duct adenoma primarily presents as intraductal growth in the CBD, usually with bile duct dilatation at the lesion site or upstream to it. Most lesions are isointense on T1WI, are hyperintense on T2WI and DWI, and show moderate enhancement. A superficial frond-like appearance of the lesion and bile duct dilatation at the lesion or downstream to it might be characteristics of bile duct adenoma. An infiltrative appearance might indicate malignant transformation.

Trick or Treat: An Intrahepatic Intraductal Papillary Neoplasm of the Bile Duct

An intraductal papillary neoplasm involving the biliary tree is an unusual premalignant condition of epithelial origin, identified by its cystic dilatation of the biliary channels. Being a slow-growing tumor, surgery offers the best curative rate, especially in the setting of a low-grade disease. Here, we present a case of a localized, low-grade, intraductal papillary neoplasm of the bile duct (IPNB), residing in the liver, which was treated with resection of the liver lobe. The adjuvant treatment and prognosis highly depend upon the presence of dysplasia or a co-existent invasive malignancy. To the best of our knowledge, being a rare entity, this is the first case to be reported from Pakistan.

Intraductal Papillary Neoplasm of the Bile Duct: A Rare Disease and Presentation

Intraductal papillary neoplasm of the bile duct (IPNB) is a rare disease that occurs anywhere along the bile duct. The disease predominantly occurs in Far East Asia and is very rarely diagnosed and documented in western countries. IPNB presents similarly to obstructive biliary pathology; however, patients can be asymptomatic. Surgical resection of IPNB lesions is crucial for patient survival because IPNB is precancerous and can transform into cholangiocarcinoma. Although potentially curative by excision with negative margins, patients who are diagnosed with IPNB need close monitoring for de novo recurrence of IPNB or other pancreatic-biliary neoplasms. In this case, we present an asymptomatic non-Hispanic Caucasian male who was diagnosed with IPNB.

Surgical Treatment of Intraductal Papillary Neoplasm of the Bile Duct: A Report of Two Cases and Review of the Literature

Intraductal papillary neoplasm of the bile duct (IPNB) is a rare bile duct tumor characterized by intraductal papillary or villous neoplasms covered by neoplastic epithelium with fine fibrovascular stalks in the dilated bile ducts (1). Its true etiology remains unknown. Herein, we report two cases of IPNB that underwent surgical resection. The first case was a 66-year-old male who complained of upper abdominal pain for three years. We found obstruction of the common bile duct and dilation of the intrahepatic and extrahepatic bile ducts after MRCP. Laparoscopic hepatic segmentectomy (S2, S3, S4), resection of the common bile duct, cholecystectomy, and hepaticojejunostomy were performed. The second case was a 67-year-old male with asymptomatic dilation of the intrahepatic duct. The patient underwent robot-assisted laparoscopic hepatic segmentectomy (S5, S6, S7, S8), resection of the common bile duct, hepaticojejunostomy and cholecystectomy.

Intraductal Papillary Neoplasm of Bile Duct: Updated Clinicopathological Characteristics and Molecular and Genetic Alterations

Intraductal papillary neoplasm of the bile duct (IPNB), a pre-invasive neoplasm of the bile duct, is being established pathologically as a precursor lesion of invasive cholangiocarcinoma (CCA), and at the time of surgical resection, approximately half of IPNBs show stromal invasion (IPNB associated with invasive carcinoma). IPNB can involve any part of the biliary tree. IPNB shows grossly visible, exophytic growth in a dilated bile duct lumen, with histologically villous/papillary neoplastic epithelia with tubular components covering fine fibrovascular stalks. Interestingly, IPNB can be classified into four subtypes (intestinal, gastric, pancreatobiliary and oncocytic), similar to intraductal papillary mucinous neoplasm of the pancreas (IPMN). IPNBs are classified into low-grade and high-grade based on lining epithelial features. The new subclassification of IPNB into types 1 (low-grade dysplasia and high-grade dysplasia with regular architecture) and 2 (high-grade dysplasia with irregular architecture) proposed by the Japan–Korea pathologist group may be useful in the clinical field. The outcome of post-operative IPNBs is more favorable in type 1 than type 2. Recent genetic studies using next-generation sequencing have demonstrated the existence of several groups of mutations of genes: (i) IPNB showing mutations in KRAS, GNAS and RNF43 belonged to type 1, particularly the intestinal subtype, similar to the mutation patterns of IPMN; (ii) IPNB showing mutations in CTNNB1 and lacking mutations in KRAS, GNAS and RNF43 belonged to the pancreatobiliary subtype but differed from IPMN. IPNB showing mutation of TP53, SMAD4 and PIK3CA might reflect complicated and other features characterizing type 2. The recent recognition of IPNBs may facilitate further clinical and basic studies of CCA with respect to the pre-invasive and early invasive stages.

Clinicopathological findings and imaging features of intraductal papillary neoplasms in bile ducts

Background

Intraductal papillary mucinous neoplasm of the bile duct (IPMN-B) is considered an uncommon tumor, and there is limited understanding of IPMN-B. This study aimed to investigate the prognosis and influential factors of the IPMN-B from 58 cases.

Methods

The clinical data of 58 patients with pathologically confirmed IPMN-B admitted to our hospital from January 1, 2012 to August 2017 were collected and analyzed. The patients were followed up by outpatient or telephone until January 1, 2019. SPSS 19.0 software was applied for data analysis. Survival analysis was performed using Kaplan-Meier method and parallel Log-rank test. Prognostic factors were analyzed by univariate analysis and multiple Cox regression model.

Results

Among of all the patients, 26 cases were benign tumors and 32 cases were malignant tumors. The preoperative tumor markers CA242 and CEA of malignant IPNM-B patients were significantly higher than those in benign tumors (P < 0.05). Survival analysis showed that patients with malignant tumors had a worse prognosis. The median survival time of malignant IPMN-B patients was 40.6 ±  3.0 months, yet median survival time of benign IPMN-B patients was not reached (P = 0.19). The one-year survival rate and three-year survival rate of benign IPMN-B were 84% and 74% respectively. The one-year survival rate and three-year survival rate of malignant IPMN-B were 88% and 64% respectively. Univariate analysis showed that combined lymph node metastasis, surgical method, and differentiation degree could affect patients’ prognosis (P < 0.05). Multivariate analysis showed differentiation degree was an independent risk factor affecting prognosis (OR = 0.06, 95% confidence interval: 0.007∼0.486, P < 0.05).

Conclusion

The levels of CEA and CA242 were helpful to identify benign and malignant of IPNM-B. Moreover, radical surgical resection could prolong patients’ survival. Finally, differentiation degree was an independent risk factor affecting malignant IPNM-B prognosis.

Branch-type intraductal papillary neoplasm of the bile duct treated with laparoscopic anatomical resection: a case report

Background

Intraductal papillary neoplasm of the bile duct (IPNB) is characterized by an intraluminal, growing papillary tumor covered by neoplastic biliary epithelial cells with a fine fibrovascular core. IPNB was introduced as a precancerous and early neoplastic lesion in the 2010 World Health Organization classification of tumors of the digestive system. IPNB eventually invades the bile duct wall and progresses to invasive cholangiocarcinoma. IPNB resembles intraductal papillary mucinous neoplasm of the pancreas (IPMN), particularly the main pancreatic duct type.

IPNB cases, possibly corresponding to branch-type IPMN, have been recently reported, and these cases involved the peribiliary glands significantly and showed gross cystic dilatation. Small branch-type intrahepatic IPNB often mimics simple liver cysts, making the diagnosis of IPNB difficult. Some literature recommended surgical resection for treatment. Laparoscopic resection is a good treatment option for small tumor. We herein present the case of branch-type IPNB that was treated with laparoscopic anatomical liver resection 5 years after being detected.

Case presentation

A 64-year-old woman was undergoing follow-up for primary aldosteronism. In 2012, follow-up computed tomography (CT) incidentally revealed a 7-mm cystic lesion in segment 8 of the liver. From 2012 to 2017, the cystic lesion kept increasing in size, reaching 17 mm. In 2017, CT also revealed a 13-mm mural nodule in the cyst wall. Therefore, the patient was referred to our department for possible malignancy.

We suspected a branch-type IPNB; however, the mass was small and diagnosis could not be made without performing biopsy. Accordingly, surgical resection was performed for diagnosis and treatment. Because branch-type IPNB might show horizontal spread through the intrahepatic bile duct, we believed that anatomical resection of the liver was appropriate considering the malignant potential of the lesion. Therefore, laparoscopic anatomical resection of segment 8 of the liver was performed. The resected tumor measured 17 mm and was histologically diagnosed as a high-grade IPNB.

Conclusion

Branch-type IPNBs are rare but can potentially lead to malignant tumors. Surgical resection is the treatment of choice, with laparoscopic anatomical resection being a good treatment option for this small tumor.

Cystic intraductal papillary neoplasms with infiltrating carcinoma of the intrahepatic bile duct: A case report

INTRODUCTION

Intraductal papillary neoplasms of the bile duct (IPNB) is a kind of rare disorder with low incidence but high misdiagnosis due to untypical symptoms and non-specific laboratory indicators. Herein, we report a case of cystic type IPNB with infiltrating carcinoma of the intrahepatic bile duct presented as a single giant cystic mass of the liver.

PATIENT CONCERNS

A 51-year-old woman was admitted due to right upper abdominal discomfort for 10 months. Physical examination indicated no specific finding. Laboratory tests showed that serum total bilirubin and carcinoembryonic antigen level was mildly elevated. Ultrasonography, computed tomography (CT) and magnetic resonance imaging (MRI) of abdomen indicated a giant lobulated cystic lesion involving the left, right and the caudate lobes of liver. There were multiple small nodules of different sizes with papillary or coral reef-like pattern protruding into the cystic lumen from the inner wall.

DIAGNOSIS

The patient was diagnosed as malignant tumors of intrahepatic bile duct.

INTERVENTIONS

She received radical resection of the lesion by hepatectomy.

OUTCOMES

The postoperative pathological examination revealed an IPNB with infiltrating carcinoma of the intrahepatic bile duct. This patient had an uneventful postoperative recovery and was discharged on day 21 post-surgery. Until 35 months after surgery, there is no recurrence or metastasis.

CONCLUSION

The CT and MRI can show certain morphologic features including the segmental cystic dilatation of intrahepatic bile ducts and the pathological details of papillary tumors inside the lesion. Cystic IPNB with infiltrating carcinoma of the intrahepatic bile duct can be treated with surgery.

A huge intraductal papillary neoplasm of the bile duct treated by right trisectionectomy after right portal vein embolization

Intraductal papillary neoplasm of the bile duct (IPNB) is a rare variant of bile duct tumors characterized by papillary growth within the bile duct lumen and recognized precursor of invasive carcinoma. IPNB was detected incidentally in a 60-year-old woman during check up. Radiologic images revealed a huge cystic mass with papillary projection and markedly dilated bile ducts. Biopsies revealed high-grade IPNB. Cholangioscopy detected a connection between the right posterior bile duct and cyst lumen with epithelial dysplasia of the bile duct. Right posterior sectional duct opened in the left hepatic duct. Consequently, right trisectionectomy and extrahepatic bile duct resection were conducted. Histological studies revealed intraductal papillary neoplasm with high-grade intraepithelial neoplasia (carcinoma in situ). IPNB patients without distant metastases are candidates for surgery and complete resection should be conducted to achieve long-term survival.