Intraductal papillary neoplasm of the bile duct: a biliary equivalent to intraductal papillary mucinous neoplasm of the pancreas?

Multiple intraductal papillary neoplasms of bile duct diagnosed based on endoscopic ultrasonography and peroral cholangioscopy findings

A man in his 30s was referred to our department for evaluation of bile duct stricture and removal of an intrahepatic bile duct stone. Five years before his presentation, he underwent left hepatectomy for a giant hepatic hemangioma. There were no abnormalities in blood biochemical tests. Magnetic resonance cholangiopancreatography showed one 5 mm oval defect in region B6 and two 8 mm semicircular defects in the hilar bile duct. Endoscopic ultrasound revealed a 3.5 mm hypoechoic focal raised lesion in the hilar bile duct. Oral cholangioscopy revealed his two lesions in the hilar bile duct as white papillary elevations with mucus production. The pathological diagnosis of intraductal papillary neoplasm was determined (low-grade dysplasia, type 1, gastric type). After 1 and a half years, no expansion of the bile duct lesion was observed. Initially, it was thought to be a benign stenosis after liver resection, but based on the results of endoscopic ultrasound, we suspected a tumorous lesion, and we were able to make an accurate diagnosis, including histological type, using transoral cholangioscopy.

Intraductal papillary neoplasm of the bile duct: diagnostic value of MRI features in differentiating pathologic subclassifications-type 1 versus type 2

OBJECTIVES

To identify MRI features for differentiating type 2 from type 1 intraductal papillary neoplasms of bile duct (IPNB) and assessing malignant potential of IPNB.

METHODS

This retrospective study included 60 patients with surgically proven IPNB who had undergone preoperative MRI between January 2007 and December 2020. All surgical specimens were reviewed retrospectively to classify types 1 and 2 IPNBs and assess tumor grade. Significant MRI features for differentiating type 2 (n = 40) from type 1 IPNB (n = 20); and for IPNB with an associated invasive carcinoma (n = 43) from intraepithelial neoplasia (n = 17) were determined using logistic regression analysis.

RESULTS

An associated invasive carcinoma was more frequently found in type 2 than in type 1 IPNB (85.0% [34/40] vs. 45.0% [9/20], p = 0.003). At univariable analysis, MRI features including extrahepatic location, no dilatation of tumor-bearing segment of bile duct, isolated upstream bile duct dilatation, and single lesion were associated with type 2 IPNB (all p ≤ 0.012). At multivariable analysis, significant MRI findings for differentiating type 2 from type 1 IPNB were extrahepatic location and no dilatation of tumor-bearing segment of bile duct (odds ratio [OR], 7.24 and 46.40, respectively). At univariable and multivariable analysis, tumor size ≥ 2.5 cm (OR, 8.45), bile duct wall thickening (OR, 4.82), and irregular polypoid or nodular tumor shape (OR, 6.44) were significant MRI features for differentiating IPNB with an associated invasive carcinoma from IPNB with intraepithelial neoplasia.

CONCLUSION

MRI with MR cholangiopancreatography may be helpful in differentiating type 2 IPNB from type 1 IPNB and assessing malignant potential of IPNB.

CLINICAL RELEVANCE STATEMENT

Preoperative MRI with MR cholangiopancreatography may be helpful in differentiating type 2 intraductal papillary neoplasms of bile duct (IPNB) from type 1 IPNB and assessing malignant potential of IPNB.

KEY POINTS

• In terms of tumor grade, the incidence of invasive carcinoma was significantly higher in type 2 intraductal papillary neoplasm of the bile duct (IPNB) than in type 1 IPNB. • At MRI, extrahepatic location and no dilatation of tumor-bearing segment are significant features for differentiating type 2 IPNBs from type 1 IPNBs. • At MRI, large tumor size, bile duct wall thickening, and irregular polypoid or nodular tumor shape are significant features for differentiating IPNB with an associated invasive carcinoma from IPNB with intraepithelial neoplasia.

Intraductal papillary neoplasms of the bile ducts: a comparative study of a rare disease in Europe and Nagoya, Japan

BACKGROUND

Intraductal papillary neoplasm of the bile ducts (IPNB) is a rare disease in Western countries. The aim of this study was to compare tumor characteristics, management strategies, and outcomes between Western and Eastern patients who underwent surgical resection for IPNB.

METHODS

A multi-institutional retrospective series of patients with IPNB undergoing surgery between January 2010 and December 2020 was gathered under the auspices of the European-African Hepato-Pancreato-Biliary Association (E-AHPBA), and at Nagoya University Hospital, Japan.

RESULTS

A total of 85 patients (51% male; median age 66 years) from 28 E-AHPBA centers were compared to 91 patients (64% male; median age 71 years) from Nagoya. Patients in Europe had more multiple lesions (23% vs 2%, P < .001), less invasive carcinoma (42% vs 85%, P < .001), and more intrahepatic tumors (52% vs 24%, P < .001) than in Nagoya. Patients in Europe experienced less 90-day grade >3 Clavien-Dindo complications (33% vs 68%, P < .001), but higher 90-day mortality rate (7.0% vs 0%, P = .03). R0 resections (81% vs 82%) were similar. Overall survival, excluding 90-day postoperative deaths, was similar in both regions.

DISCUSSION

Despite performing more extensive resections, the low perioperative mortality rate observed in Nagoya was probably influenced by a combination of patient-, tumor-, and surgery-related factors.

Intraductal Papillary Neoplasm of the Bile Duct Treated with Argon Plasma Coagulation via Endoscopic Ultrasound-guided Choledochoduodenostomy

A 93-year-old man presented to our hospital with a fever, abdominal pain, and jaundice. Computed tomography revealed bilateral bile duct dilation, cystic lesions with bile duct communication, and intraluminal solid nodules arising from the bile duct wall. The patient was diagnosed with intraductal papillary neoplasm of the bile duct. Surgery was not performed, considering the patient's age. It was impossible to control cholangitis using conventional endoscopic therapy. We therefore created an access route to the bile duct using endoscopic ultrasound-guided choledochoduodenostomy and inserted a lumen-apposed metal stent. Thereafter, we performed argon plasma coagulation of the tumor in the bile duct, which successfully prevented cholangitis recurrence.

Intraductal papillary neoplasm of the bile duct: A case report of a rare tumor with a brief review of literature

INTRODUCTION AND IMPORTANCE

Intraductal papillary neoplasm of the bile duct (IPNB) is a rare neoplasm, mostly found in patients from far Eastern areas where hepatolithiasis and clonorchiasis are endemic. Very few cases are reported from India.

CASE PRESENTATION

We present a case of recurrent cholangitis in a 59-year-old male, initially suspected to have IPNB based on preoperative imaging. Confirmation occurred intraoperatively, with mucin-filled bile ducts and papillary lesions in the resected hepatic duct. Treatment included left hepatectomy, extrahepatic bile duct excision, and Roux-en-Y hepaticojejunostomy. Histopathology indicated invasive pancreatobiliary-type IPNB with clear margins. The patient experienced post-hepatectomy hepatic insufficiency and superficial incisional surgical site wound infection, managed conservatively. Discharge occurred on postoperative day 21, with satisfactory recovery at the 16-month follow-up.

CLINICAL DISCUSSION

IPNB is recognized as the biliary equivalent of intraductal papillary mucinous neoplasm, as these two conditions exhibit multiple commonalities in terms of clinical and histopathological characteristics. The unique aspect of our case lies in the intricacies associated with its diagnosis. Initially, imaging modalities did not yield a definitive characterization of the lesion. Notably, the endoscopist misinterpreted mucin expression emanating from the papilla as purulent material, primarily due to the patient's concurrent cholangitis. Subsequent repetitions of both CT scan and MRI provided some valuable insights that contributed to the diagnostic clarity of the IPNB.

CONCLUSION

In cases of symptoms like biliary obstruction with bile duct dilation, wall nodules, papillary/solid-cystic masses, and upstream-downstream dilation, IPNB should be considered. Striving for R0 resection is crucial for enhanced long-term patient survival.

MRI features of intraductal papillary mucinous neoplasm of the bile ducts, "The myth about the cyst": A systematic review

Rationale and objectives

Intraductal papillary mucinous neoplasm of the bile ducts (IPMN-B) is a true pre-cancerous lesion, which shares common features with pancreatic IPMN (IPMN-P). While IPMN-P is a well described entity for which guidelines were formulated and revised, IPMN-B is a poorly described entity.We carried out a systematic review to evaluate the existing literature, emphasizing the role of MRI in IPMN-B depiction.

Materials and methods

PubMed database was used to identify original studies and case series that reported MR Imaging features of IPMN-B. The search keywords were "IPMN OR intraductal papillary mucinous neoplasm OR IPNB OR intraductal papillary neoplasm of the bile duct AND Biliary OR biliary cancer OR hepatic cystic lesions". Risk of bias and applicability were evaluated using the QUADAS-2 tool.

Results

884 Records were Identified through database searching. 12 studies satisfied the inclusion criteria, resulting in MR features of 288 patients. All the studies were retrospective. Classic features of IPMN-B are under-described. Few studies note worrisome features, concerning for an underlying malignancy. 50 % of the studies had a high risk of bias and concerns regarding applicability.

Conclusions

The MRI features of IPMN-B are not well elaborated and need to be further studied. Worrisome features and guidelines regarding reporting the imaging findings should be established and published. Radiologists should be aware of IPMN-B, since malignancy diagnosis in an early stage will yield improved prognosis.

Tumoral Intraductal Neoplasms of the Bile Ducts Comprise Morphologically and Genetically Distinct Entities

CONTEXT.—

Tumoral (grossly visible) intraductal neoplasms of the bile ducts are still being characterized.

OBJECTIVE.—

To investigate their morphologic, immunohistochemical, and molecular features.

DESIGN.—

Forty-one cases were classified as gastric-, intestinal-, pancreatobiliary-type intraductal papillary neoplasm (IPN), intraductal oncocytic papillary neoplasm (IOPN), or intraductal tubulopapillary neoplasm (ITPN) on the basis of histology. All neoplasms were subjected to targeted next-generation sequencing.

RESULTS.—

The mean age at diagnosis was 69 years (42-81 years); male to female ratio was 1.3. Most neoplasms (n = 23, 56%) were extrahepatic/large (mean size, 4.6 cm). The majority (n = 32, 78%) contained high-grade dysplasia, and 68% (n = 28) revealed invasion. All gastric-type IPNs (n = 9) and most ITPNs/IOPNs showed consistent colabeling for CK7/MUC6, which was less common among others (P = .004). Intestinal-type IPNs (n = 5) showed higher rates of CK20 expression than others (P < .001). Overall, the most commonly mutated genes included TP53 and APC, while copy number variants affected ELF3 and CDKN2A/B. All gastric-type IPNs contained an alteration affecting the Wnt signaling pathway; 7 of 9 (78%) showed aberrations in the MAPK pathway. Mutations in APC and KRAS were common in gastric-type IPNs as compared with others (P = .01 for both). SMAD4 was more frequently mutated in intestinal-type IPNs (P = .02). Pancreatobiliary-type IPNs (n = 14) exhibited frequent alterations in tumor suppressor genes including TP53, CDKN2A/B, and ARID2 (P = .04, P = .01 and P = .002, respectively). Of 6 IOPNs analyzed, 3 (50%) revealed ATP1B1-PRKACB fusion. ITPNs (n = 6) showed relatively few recurrent genetic aberrations. Follow-up information was available for 38 patients (median, 58.5 months). The ratio of disease-related deaths was higher for the cases with invasion (56% versus 10%).

CONCLUSIONS.—

Tumoral intraductal neoplasms of the bile ducts, similar to their counterparts in the pancreas, are morphologically and genetically heterogeneous.

Intraductal papillary neoplasm of the bile duct: The new frontier of biliary pathology

Intraductal papillary neoplasms of the bile duct (IPNBs) represent a rare variant of biliary tumors characterized by a papillary growth within the bile duct lumen. Since their first description in 2001, several classifications have been proposed, mainly based on histopathological, radiological and clinical features, although no specific guidelines addressing their management have been developed. Bile duct neoplasms generally develop through a multistep process, involving different precursor pathways, ranging from the initial lesion, detectable only microscopically, i.e. biliary intraepithelial neoplasia, to the distinctive grades of IPNB until the final stage represented by invasive cholangiocarcinoma. Complex and advanced investigations, mainly relying on magnetic resonance imaging (MRI) and cholangioscopy, are required to reach a correct diagnosis and to define an adequate bile duct mapping, which supports proper treatment. The recently introduced subclassifications of types 1 and 2 highlight the histopathological and clinical aspects of IPNB, as well as their natural evolution with a particular focus on prognosis and survival. Aggressive surgical resection, including hepatectomy, pancreaticoduodenectomy or both, represents the treatment of choice, yielding optimal results in terms of survival, although several endoscopic approaches have been described. IPNBs are newly recognized preinvasive neoplasms of the bile duct with high malignant potential. The novel subclassification of types 1 and 2 defines the histological and clinical aspects, prognosis and survival. Diagnosis is mainly based on MRI and cholangioscopy. Surgical resection represents the mainstay of treatment, although endoscopic resection is currently applied to nonsurgically fit patients. New frontiers in genetic research have identified the processes underlying the carcinogenesis of IPNB, to identify targeted therapies.

Intraductal papillary neoplasm of the bile duct: review of updated clinicopathological and imaging characteristics

BACKGROUND

Intraductal papillary neoplasm of the bile duct (IPNB) is a relatively rare disease and is known as one of the premalignant lesions in the biliary tract. The concept of IPNB has changed through numerous studies and is still evolving. As a lesser studied clinical entity compared with its pancreatic counterpart, intraductal papillary mucinous neoplasm, IPNB has been described in many similar terms, including biliary papillomatosis, biliary intraductal papillary-mucinous neoplasm, and papillary cholangiocarcinoma. This is based on the diversity of histopathological spectrum of IPNB.

METHODS

This review investigated previous studies including original articles, case studies, and expert opinions. Recently, two types of IPNB (types 1 and 2) have been proposed and validated based on the content first established in the WHO 2010 criteria.

RESULTS

This review provides a comprehensive analysis of existing literature, summarizing the clinical, radiological, morphological, and pathological characteristics of IPNB.

CONCLUSION

Given the ongoing ambiguity and controversies surrounding IPNB, future research, including large population-based studies and molecular investigations, is essential to enhance understanding of this disease.

Intraductal papillary mucinous neoplasm of the biliary tract in the caudate lobe of the liver: a case report and literature review

An intraductal papillary mucinous neoplasm of the biliary tract (BT-IPMN) in the caudate lobe of the liver is a rare tumor originating from the bile duct. Approximately 40% of the intraductal papillary neoplasms of the biliary tract (IPNB) secrete mucus and can grow in the intrahepatic or extrahepatic bile ducts. A 65-year-old woman presented with recurrent episodes of right upper pain. She developed her first episode 8 years ago, which resolved spontaneously. The frequency of symptoms has increased in the last 2 years. She underwent laparoscopic hepatectomy and choledochal exploration and was pathologically diagnosed with a rare BT-IPMN of the caudate lobe after admission. Here, we review studies on IPNB cases and systematically describe the pathological type, diagnosis, and treatment of IPNB to provide a valuable reference for hepatobiliary surgeons in the diagnosis and treatment of this disease.

Intraductal papillary mucinous neoplasm of the intrahepatic bile duct: a review of literature and a rare case report

Background

Intraductal papillary neoplasm of the bile duct is a rare variant of bile duct tumors, which is characterized by papillary or villous growth inside the bile duct. Having papillary and mucinous features such as those found in pancreatic intraductal papillary mucinous neoplasm (IPMN) is extremely rare. We report a rare case of intraductal papillary mucinous neoplasm of the intrahepatic bile duct.

Case report

A 65-year-old male Caucasian with multiple comorbidities presented to the emergency room with moderate constant pain at the right upper quadrant (RUQ) abdomen for the last several hours. On physical examination, he was found to have normal vital signs, with icteric sclera and pain on deep palpation at the RUQ region. His laboratory results were significant for jaundice, elevated liver function tests and creatinine, hyperglycemia, and leukocytosis. Multiple imaging studies revealed a 5 cm heterogeneous mass in the left hepatic lobe that demonstrated areas of internal enhancement, mild gall bladder wall edema, dilated gall bladder with mild sludge, and 9 mm common bile duct (CBD) dilatation without evidence of choledocholithiasis. He underwent a CT-guided biopsy of this mass, which revealed intrahepatic papillary mucinous neoplasm. This case was discussed at the hepatobiliary multidisciplinary conference, and the patient underwent an uneventful robotic left partial liver resection, cholecystectomy, and lymphadenectomy.

Conclusion

IPMN of the biliary tract may represent a carcinogenesis pathway different from that of CBD carcinoma arising from flat dysplasia. Complete surgical resection should be performed whenever possible because of its significant risk of harboring invasive carcinoma.

Epidemiology and outcome of individuals with intraductal papillary neoplasms of the bile duct

BACKGROUND

Intraductal papillary neoplasm of the bile duct (IPNB) is a rare distinct subtype of precursor lesions of biliary carcinoma. IPNB is considered to originate from luminal biliary epithelial cells, typically displays mucin-hypersecretion or a papillary growth pattern, and results in cystic dilatation[1]. IPNB develops anywhere in the intrahepatic and extrahepatic biliary tracts, and can occur in various pathological stages from low-grade dysplasia to invasive carcinoma. IPNBs have similar phenotypic changes in the occurrence and development of all subtypes, and the prognosis is significantly better than that of traditional (non-papillary) cholangiocarcinoma.

AIM

To evaluate the clinicopathological features of IPNB to provide evidence-based guidance for treatment.

METHODS

Invasive IPNB, invasive intraductal papillary mucinous neoplasm of the pancreas (IPMN), and traditional cholangiocarcinoma data for affected individuals from 1975 to 2016 were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Annual percentage changes (APCs) in the incidence and incidence-based (IB) mortality were calculated. We identified the independent predictors of overall survival (OS) and cancer-specific survival (CSS) in individuals with invasive IPNB.

RESULTS

The incidence and IB mortality of invasive IPNB showed sustained decreases, with an APC of -4.5% (95%CI: -5.1% to -3.8%) and -3.3% (95%CI: -4.1% to -2.6%) (P < 0.001), respectively. Similar decreases in incidence and IB mortality were seen for invasive IPMN but not for traditional cholangiocarcinoma. Both OS and CSS for invasive IPNB were better than for invasive IPMN and traditional cholangiocarcinoma. A total of 1635 individuals with invasive IPNB were included in our prognosis analysis. The most common tumor sites were the pancreaticobiliary ampulla (47.9%) and perihilar tract (36.7%), but the mucin-related subtype of invasive IPNB was the main type, intrahepatically (approximately 90%). In the univariate and multivariate Cox regression analysis, age, tumor site, grade and stage, subtype, surgery, and chemotherapy were associated with OS and CSS (P < 0.05).

CONCLUSION

Incidence and IB mortality of invasive IPNB trended steadily downward. The heterogeneity of IPNB comprises site and the tumor’s mucin-producing status.

Intraductal papillary neoplasms of the bile duct: a European retrospective multicenter observational study (EUR-IPNB study)

BACKGROUND/PURPOSE

Intraductal papillary neoplasm of the bile duct (IPNB) is a rare disease in Western countries. The main aim of this study was to characterize current surgical strategies and outcomes in the mainly European participating centers.

METHODS

A multi-institutional retrospective series of patients with a diagnosis of IPNB undergoing surgery between 1 January 2010 and 31 December 2020 was gathered under the auspices of the European-African Hepato-Pancreato-Biliary Association. The textbook outcome (TO) was defined as a non-prolonged length of hospital stay plus the absence of any Clavien-Dindo grade at least III complications, readmission, or mortality within 90 postoperative days.

RESULTS

A total of 28 centers contributed 85 patients who underwent surgery for IPNB. The median age was 66 years (55-72), 49.4% were women, and 87.1% were Caucasian. Open surgery was performed in 72 patients (84.7%) and laparoscopic in 13 (15.3%). TO was achieved in 54.1% of patients, reaching 63.8% after liver resection and 32.0% after pancreas resection. Median overall survival was 5.72 years, with 5-year overall survival of 63% (95% CI: 50-82). Overall survival was better in patients with Charlson comorbidity score 4 or less versus more than 4 ( P =0.016), intrahepatic versus extrahepatic tumor ( P =0.027), single versus multiple tumors ( P =0.007), those who underwent hepatic versus pancreatic resection ( P =0.017), or achieved versus failed TO ( P =0.029). Multivariable Cox regression analysis showed that not achieving TO (HR: 4.20; 95% CI: 1.11-15.94; P =0.03) was an independent prognostic factor of poor overall survival.

CONCLUSIONS

Patients undergoing liver resection for IPNB were more likely to achieve a TO outcome than those requiring a pancreatic resection. Comorbidity, tumor location, and tumor multiplicity influenced overall survival. TO was an independent prognostic factor of overall survival.

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.

Intraductal tubulopapillary neoplasms of the bile ducts: identity, clinicopathologic characteristics, and differential diagnosis of a distinct entity among intraductal tumors

Among the mass-forming preinvasive (tumoral intraepithelial) neoplasms of the biliary tract, intraductal tubulopapillary neoplasms (ITPN-Bs) are increasingly being recognized as a separate category. By being intramucosal polypoid proliferations of dysplastic/neoplastic cells, they are highly similar to other members of the "intraductal neoplasms (IDNs)" category (namely, intraductal papillary neoplasms [IPNBs], and intraductal oncocytic papillary neoplasms [IOPNs]); however, they are distinguished by MUC6-expressing nonmucinous cells that lack intestinal differentiation and form striking tubular configuration. Their molecular/genetic profile is also proving to be different with frequent alterations in cell cycle and chromatin remodeling genes, which are quite uncommon in other IDNs and cholangiocarcinomas. Despite the conceptual overlaps, they are also very different from intracholecystic nonmucinous tubular neoplasms (ICTN) of the gallbladder with the latter being associated with Wnt/beta-catenin pathway alterations, and almost never invasive. In contrast, ITPN-Bs are invasive in an estimated 80% of the cases, although even invasive examples often exhibit a protracted course. Invasive carcinomas arising from ITPN-Bs are overall similar to cholangiocarcinomas (including small duct and large duct patterns) but also often have peculiar characteristics such as more nodular-compact (blunt invasion) pattern. Like other IDNs, the ITPN-Bs have also been classified in the past as intraductal-spreading type of cholangiocarcinomas (and they are still regarded as such in some publications). In small biopsies, they are prone to be mistaken as ordinary adenocarcinomas because of their tubular pattern and pancreatobiliary cytology although their relatively monotonous cytology and zones of back-to-back tubule formation can help in their correct identification. Clinical presentation of ITPN-Bs is generally similar to other intraductal neoplasms; however, in the intrahepatic component, they tend to be more nodular than cystic, and their snake-like intraductal growth pattern is often more striking. In the management (diagnosis and treatment) of these tumors that are in essence adenoma-carcinoma sequence, the invasive and noninvasive components ought to be evaluated separately. Minimally invasive examples are commonly curable, and even those more extensively invasive may have a surprisingly good prognosis. In summary, biliary ITPNs form a distinct category not only clinicopathologically, immunophenotypically, and molecular-wise but regarding their biological behavior as well.

Hepatobiliary mucinous cystic neoplasms and mimics

This review will provide an overview of hepatobiliary mucinous cystic neoplasms and their mimics such as complex appearing benign cysts, intraductal papillary neoplasm of bile ducts, choledochal cysts, infectious cysts, and other cystic neoplasms. Preoperative imaging, particularly abdominal MRI with MRCP, plays a key role in differentiating these entities which differ widely in management. Familiarity with the differentiating imaging features of mucinous cystic neoplasms and their mimics allows radiologists to provide management-guiding reports.

Unconventional treatment of inoperable biliary IPMN with an oesophageal stent in the common bile duct: case report

Biliary intraductal papillary mucinous neoplasm (IPMN) is a rare biliary neoplasia preferably treated with oncologic resection. Endoscopic radio frequency (RF) ablation may be used as a palliative measure. We present a rare case, where heavy co-morbidities prevented surgery. Continuous mucus production caused recurrent episodes of severe cholangitis. Several ERCPs (endoscopic retrograde cholangio pancretography) were necessary due to recurrent biliary obstruction. RF ablation was not effective in the dilated common bile duct without a stricture. Standard biliary stents failed due to either migration or occlusion. When other options failed, an exceptional decision was made: a covered large diameter oesophageal stent was inserted in ERCP into the bile duct to secure bile flow and stop mucus production. Digital cholangioscopy was crucial adjunct to standard ERCP in endoscopic management. The palliative treatment method was successful: there were no stent-related adverse events or readmissions for cholangitis. The follow-up in the palliative care lasted until patient's last 10 months of lifetime.

Clinicopathological Features and Long-Term Outcomes of Intraductal Papillary Neoplasms of the Bile Duct of the Liver: Single-Institution Experience with 146 Patients

BACKGROUND

Intraductal papillary neoplasm of the bile duct (IPNB) has a wide range of histopathology and intra- and extrahepatic tumor locations.

METHODS

This retrospective single-center study evaluated the clinicopathological features and long-term outcomes of 146 patients with IPNB of the liver (IPNB-L) who underwent hepatic resection between January 2002 and June 2019.

RESULTS

The 146 patients included 97 (66.4%) men and 49 (33.6%) women, of mean age 64.3 ± 8.0 years. Seventy-two (49.3%) patients were incidentally diagnosed, with no specific symptoms, and 18 (12.3%) were found to have hepatolithiasis. Sixty-one (41.8%) and two (1.4%) patients underwent concurrent bile duct resection and pancreaticoduodenectomy, respectively, and 130 (89.0%) underwent R0 resection. Low-grade and high-grade intraepithelial neoplasia, and invasive carcinoma were identified in 26 (17.8%), 50 (34.2%), and 70 (47.9%) patients, respectively. Five-year tumor recurrence and patient survival rates were 8.4% and 93.9%, respectively, in patients with high-grade neoplasia; and 41.5% and 72.3%, respectively, in patients with invasive carcinoma. CA19-9 > 37 U/mL and R1 resection were independent risk factors for tumor recurrence and reduced survival in patients with carcinoma. The combination of hypermetabolic fluorodeoxy-glucose-positron emission tomography (FDG-PET) or elevated CA19-9 showed a sensitivity of 91.8% and a specificity of 61.9% for the prediction of IPNB-L with high-grade neoplasia and carcinoma.

CONCLUSIONS

IPNB-L is a rare type of intrahepatic biliary neoplasm that can range histologically from benign disease to invasive carcinoma. Surgical curability is the most important prognostic factor, thus aggressive resection is highly recommended to achieve R0 resection.

Comparison of the Malignant Predictors in Intrahepatic and Extrahepatic Intraductal Papillary Neoplasm of the Bile Duct

Background: Intraductal papillary neoplasm of the bile duct (IPNB) is a precancerous lesion of cholangiocarcinoma, for which surgical resection is the most effective treatment. We evaluated the predictors of malignancy in IPNB according to anatomical location and the prognosis without surgery. Methods: A total of 196 IPNB patients who underwent pathologic confirmation by surgical resection or endoscopic retrograde cholangiography or percutaneous transhepatic cholangioscopic biopsy were included. Clinicopathological findings of IPNB with invasive carcinoma or mucosal dysplasia were analyzed according to anatomical location. Results: Of the 116 patients with intrahepatic IPNB (I-IPNB) and 80 patients with extrahepatic IPNB (E-IPNB), 62 (53.4%) and 61 (76.3%) were diagnosed with invasive carcinoma, respectively. Multivariate analysis revealed that mural nodule > 12 mm (p = 0.043) in I-IPNB and enhancement of mural nodule (p = 0.044) in E-IPNB were predictive factors for malignancy. For pathologic discrepancy before and after surgery, IPNB has a 71.2% sensitivity and 82.3% specificity. In the non-surgical IPNB group, composed of nine I-IPNB and seven E-IPNB patients, 43.7% progressed to IPNB with invasive carcinoma within 876 days. Conclusions: E-IPNB has a higher rate of malignancy than I-IPNB. The predictive factor for malignancy is mural nodule > 12 mm in I-IPNB and mural nodule enhancement in E-IPNB.

Up-to-Date Pathologic Classification and Molecular Characteristics of Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA) is an aggressive primary liver malignancy with an increasing incidence worldwide. Recently, histopathologic classification of small duct type and large duct type iCCA has been introduced. Both these types of tumors exhibit differences in clinicopathological features, mutational profiles, and prognosis. Small duct type iCCA is composed of non-mucin-producing cuboidal cells, whereas large duct type iCCA is composed of mucin-producing columnar cells, reflecting different cells of origin. Large duct type iCCA shows more invasive growth and poorer prognosis than small duct type iCCA. The background liver of small duct type iCCA often shows chronic liver disease related to hepatitis B or C viral infection, or alcoholic or non-alcoholic fatty liver disease/steatohepatitis, in contrast to large duct type iCCA that is often related to hepatolithiasis and liver fluke infection. Cholangiolocarcinoma is a variant of small duct type iCCA composed of naïve-looking cuboidal cells forming cords or ductule-like structures, and shows better prognosis than the conventional small duct type. Fibrous tumor stroma, one of the characteristic features of iCCA, contains activated fibroblasts intermixed with innate and adaptive immune cells. The types of stroma (mature versus immature) are related to tumor behavior and prognosis. Low tumor-infiltrating lymphocyte density, KRAS alteration, and chromosomal instability are related to immune-suppressive tumor microenvironments with resistance to programmed death 1/ programmed death ligand 1 blockade. Data from recent large-scale exome analyses have revealed the heterogeneity in the molecular profiles of iCCA, showing that small duct type iCCA exhibit frequent BAP1, IDH1/2 hotspot mutations and FGFR2 fusion, in contrast to frequent mutations in KRAS, TP53, and SMAD4 observed in large duct type iCCA. Multi-omics analyses have proposed several molecular classifications of iCCA, including inflammation class and proliferation class. The inflammation class is enriched in inflammatory signaling pathways and expression of cytokines, while the proliferation class has activated oncogenic growth signaling pathways. Diverse pathologic features of iCCA and its associated multi-omics characteristics are currently under active investigation, thereby providing insights into precision therapeutics for patients with iCCA. This review provides the latest knowledge on the histopathologic classification of iCCA and its associated molecular features, ranging from tumor microenvironment to genomic and transcriptomic research.

Imaging mimickers of cholangiocarcinoma: a pictorial review

Cholangiocarcinoma (CCA) is the second most common primary hepatobiliary malignancy and presents as three separate morphological subtypes; namely mass-forming, periductal-infiltrating, and intraductal-growing patterns. Each of these subtypes have distinct imaging characteristics, as well as a variety of benign and malignant mimics, making accurate diagnosis of CCA on imaging challenging. Whilst histopathological examination is required to arrive at a definitive diagnosis, it is still important for radiologists to be cognizant of these entities and provide reasonable differential diagnoses, as these potentially have a large impact on patient management. This pictorial essay illustrates the three morphological subtypes of CCA, as well as some important mimics for each subtype, that are encountered in clinical practice.

A Review of Mucinous Cystic and Intraductal Neoplasms of the Pancreatobiliary Tract

CONTEXT.—

Although most pancreatic and bile duct neoplasms are solid, mucinous cystic neoplasms and intraductal neoplasms have been increasingly recognized even when clinically silent, thanks to the increased use of sensitive imaging techniques. Cystic and intraductal neoplasms of the pancreas are often resectable and curable and constitute about 5% of all pancreatic neoplasms. Owing to their preinvasive nature and different biology, recognition of these entities remains a major priority. Mucinous cystic neoplasms are histologically and clinically distinct from other cystic pancreatic neoplasms. Pancreatic intraductal neoplasms encompass 3 major entities: intraductal papillary mucinous neoplasm, intraductal oncocytic papillary neoplasm, and intraductal tubulopapillary neoplasm. Intraductal papillary neoplasms of bile ducts are also preinvasive mass-forming neoplasms with both similarities and differences with their pancreatic counterparts. All of these pancreatobiliary neoplasms have diverse and distinctive clinicopathologic, genetic, and prognostic variations.

OBJECTIVE.—

To review the clinical, pathologic, and molecular features of mucinous cystic and intraductal neoplasms of the pancreatobiliary tract.

DATA SOURCES.—

Literature review, diagnostic manuals, and guidelines.

CONCLUSIONS.—

This review will briefly describe well-known clinical and pathologic features and will focus on selected recently described aspects of morphology, grading, classification, and genomic alterations of cystic and intraductal neoplasms of the pancreatobiliary tract.

Integrative analysis reveals early and distinct genetic and epigenetic changes in intraductal papillary and tubulopapillary cholangiocarcinogenesis

OBJECTIVE

A detailed understanding of the molecular alterations in different forms of cholangiocarcinogenesis is crucial for a better understanding of cholangiocarcinoma (CCA) and may pave the way to early diagnosis and better treatment options.

DESIGN

We analysed a clinicopathologically well-characterised patient cohort (n=54) with high-grade intraductal papillary (IPNB) or tubulopapillary (ITPN) neoplastic precursor lesions of the biliary tract and correlated the results with an independent non-IPNB/ITPN associated CCA cohort (n=294). The triplet sample set of non-neoplastic biliary epithelium, precursor and invasive CCA was analysed by next generation sequencing, DNA copy number and genome-wide methylation profiling.

RESULTS

Patients with invasive CCA arising from IPNB/ITPN had better prognosis than patients with CCA not associated with IPNB/ITPN. ITPN was localised mostly intrahepatic, whereas IPNB was mostly of extrahepatic origin. IPNB/ITPN were equally associated with small-duct and large-duct type intrahepatic CCA. IPNB exhibited mutational profiles of extrahepatic CCA, while ITPN had significantly fewer mutations. Most mutations were shared between precursor lesions and corresponding invasive CCA but ROBO2 mutations occurred exclusively in invasive CCA and CTNNB1 mutations were mainly present in precursor lesions. In addition, IPNB and ITPN differed in their DNA methylation profiles and analyses of latent methylation components suggested that IPNB and ITPN may have different cells-of-origin.

CONCLUSION

Integrative analysis revealed that IPNB and ITPN harbour distinct early genetic alterations, IPNB are enriched in mutations typical for extrahepatic CCA, whereas ITPN exhibited few genetic alterations and showed distinct epigenetic profiles. In conclusion, IPNB/ITPN may represent a distinctive, intermediate form of intrahepatic and extrahepatic cholangiocarcinogenesis.

Multicentric recurrence of intraductal papillary neoplasm of bile duct after spontaneous detachment of primary tumor: A case report

BACKGROUND

Intraductal papillary neoplasm of the bile duct (IPNB) rarely recurs in a multicentric manner. We encountered a patient with multiple recurrences of the gastric subtype of IPNB one year after spontaneous detachment of the primary tumor during peroral cholangioscopy (POCS).

CASE SUMMARY

A 68-year-old woman on maintenance hemodialysis because of lupus nephritis had several cardiovascular diseases and a pancreatic intraductal papillary mucinous neoplasm (IPMN). She was referred to our department for dilation of the common bile duct (CBD) and a tumor in the lumen, detected using ultrasonography. She had no complaints, and blood tests of hepatobiliary enzymes were normal. Magnetic resonance cholangiopancreatography (MRCP) showed a papillary tumor in the CBD with a filling defect detected using endoscopic retrograde cholangiography (ERC). Intraductal ultrasonography revealed a papillary tumor and stalk at the CBD. During POCS, the tumor spontaneously detached with its stalk into the CBD. Pathology showed low-intermediate nuclear atypia of the gastric subtype of IPNB. After 1 year, follow-up MRCP showed multiple tumors distributed from the left hepatic duct to the CBD. ERC and POCS showed multicentric tumors. She was alive without hepatobiliary symptoms at least two years after initial diagnosis of IPNB.

CONCLUSION

The patient experienced gastric subtype of IPNB without curative resection. Observation may be reasonable for patients with this subtype.

Intraductal papillary neoplasm of bile duct with invasive carcinoma as an intrahepatic cystic lesion, with successful preoperative diagnosis

An 82-year-old man presented to the emergency department with abdominal pain and febrile symptoms that had been present for 4 days. Blood tests showed elevated liver enzymes and white blood cell count, and abdominal contrast-enhanced CT revealed a 35 mm cystic lesion in the left lateral liver lobe. On closer examination, the cystic lesion was found to have contiguous bile duct dilatation and internal nodules. Furthermore, mucus production was observed during endoscopic retrograde cholangiopancreatography, which led to the diagnosis of intraductal papillary neoplasm of the bile duct (IPNB), with cystic infection. Although the patient was an older adult, there was no background disease that would have prevented surgery, and resection was performed. Pathological examination revealed type 1 IPNB, with invasive carcinoma. The number of reports of IPNB is expected to increase with an increasing older population in Asia, and we report the findings of this case.

Diagnostic and prognostic impact of fluorodeoxyglucose-positron emission tomography in diagnosing intraductal papillary neoplasms of the bile duct of the liver

Purpose

Malignant intraductal papillary neoplasm of the bile duct of the liver (IPNB-L) cannot readily be diagnosed through preoperative CT or MRI, but fluorodeoxyglucose (FDG)-PET is a viable alternative. This study evaluated the diagnostic and prognostic impacts of FDG-PET in patients with IPNB-L.

Methods

This was a retrospective single-center study of 101 IPNB-L patients who underwent hepatectomy between 2010 and 2019.

Results

Mean age was 64.4 ± 8.3 years and 76 (75.2%) were male. Anatomical hepatic resection was performed in 99 (98.0%). Concurrent bile duct resection and pancreaticoduodenectomy were performed in 41 (40.6%) and 1 (1.0%), respectively. R0 and R1 resections were performed in 88 (87.1%) and 13 (12.9%), respectively. Low-grade intraepithelial neoplasia and high-grade neoplasia/invasive carcinoma were diagnosed in 19 (18.8%) and 82 (81.2%), respectively. Median FDG-PET maximal standardized uptake values (SUVmax) in low-grade neoplasia and high-grade neoplasia/carcinoma were 3.6 (range, 1.7–7.6) and 5.2 (range, 1.5–18.7) (P = 0.019), respectively. Receiver operating characteristic curve analysis of SUVmax showed area under the curve of 0.674, with sensitivity of 84.2% and specificity of 47.4% at SUVmax cutoff of 3.0. This cutoff had no significant influence on tumor recurrence (P = 0.832) or patient survival (P = 0.996) in patients with IPNB-L of high-grade neoplasia or invasive carcinoma.

Conclusion

IPNB-L is a rare type of biliary neoplasm and encompasses a histological spectrum ranging from benign disease to invasive carcinoma. An FDG-PET SUVmax cutoff of 3.0 appears to effectively discern high-grade neoplasia/carcinoma from low-grade neoplasia, which will assist with the surgical strategy for these cases.

Magnetic Resonance Diffusion-Weighted Imaging for Detecting Fundal Intracholecystic Papillary Neoplasm inside Rokitansky-Aschoff Sinuses: A Comparison of Two Cases and a Literature Review

Rokitansky-Aschoff sinuses (RAS) are a common imaging finding in gallbladder adenomyomatosis (ADM), often presenting as fundal cystic spaces. Intracholecystic papillary neoplasm (ICPN) is a relatively uncommon pre-invasive tumor of the gallbladder epithelium that rarely involves RAS mucosa. We compare two cases that showed similar fundal cystic spaces resembling RAS, in which Magnetic Resonance Diffusion-Weighted Imaging (MR-DWI) was valuable for detecting (or ruling out) an underlying malignant ICPN. Evidence from the literature overall supports the role of MR-DWI for detecting intracholecystic malignant tissue.

Curative intent radical cholecystectomy followed by hyperthermic intraperitoneal chemotherapy in ruptured intraductal papillary neoplasm of gallbladder with invasive carcinoma

Gallbladder cancer has a poor prognosis, especially in peritoneal carcinomatosis related to perforation of the gallbladder followed by bile spillage. Previously, curative-intent treatment was not considered in carcinomatosis from cancer of the biliary tract. A 72-year-old male was referred to the hospital with a perforated gallbladder cancer. Intraoperatively, the tumor was confined to the gallbladder and liver. We presented a case of intention-to-curative resection of perforated gallbladder cancer followed by intraoperative hyperthermic intraperitoneal chemotherapy.

Recurrent intraductal papillary neoplasm of the bile duct due to intraductal dissemination: a case report and literature review

Background

Intraductal papillary neoplasm of the bile duct (IPNB) is a subtype of biliary tumor. The 5-year survival rate of patients with IPNB who underwent curative resection is 81%. However, IPNB is known to often recur in other parts of the bile duct. Nevertheless, its mechanism remains poorly understood. Herein, we report the case of a patient with recurrent IPNB, which was considered to be attributed to intraductal dissemination in the common bile duct at 12 months after curative resection. We also made a review of the existing literature.

Case presentation

A 69-year-old man was referred to our hospital for the evaluation and dilation of an intrahepatic bile duct (IHBD) mass. Computed tomography (CT) findings confirmed a mass in the left hepatic duct. Left trisectionectomy, extrahepatic bile duct resection with biliary reconstruction, and regional lymph node dissection were performed. Intraoperative examination of the resection margin at the common bile duct and posterior segmental branch of the hepatic duct was negative for the presence of malignant cells. Histologically, the tumor showed intraductal papillary growth of the mucinous epithelium and was diagnosed as non-invasive IPNB. It had a papillary structure with atypical epithelial cells lined up along the neoplastic fibrovascular stalks. Immunohistochemically, this was as a gastric-type lesion. At 12 postoperative months, CT revealed a 1.5-cm mass in the lower remnant common bile duct. We performed subtotal stomach-preserving pancreaticoduodenectomy. The tumor exhibited papillary growth and was microscopically and immunohistochemically similar to the first tumor. At approximately 16 months after the patient’s second discharge, CT showed an abdominal mass at the superior mesenteric plexus, which was diagnosed as recurrent IPNB. Chemotherapy is ongoing, and the patient is still alive. In this case, as described in many previous reports, IPNB recurred below the primary lesion in the bile duct.

Conclusion

Based on our review of previous reports on IPNB recurrence, intraductal dissemination was considered one of the mechanisms underlying recurrence after multicentric development. Considering the high frequency and oncological conversion of recurrence in IPNB, regular follow-up examination is essential to achieve better prognosis in patients with recurrent IPNB.

Intracholecystic papillary neoplasm of the gallbladder diagnosed during follow-up of Menetrier's disease: A case report

Intracholecystic papillary neoplasm of the gallbladder (ICPN) is a type of intraductal papillary neoplasm of the bile duct that occurs in the gallbladder, and is a relatively newer concept. Therefore, there are few reports regarding ICPN. Menetrier's disease is a rare disease characterized by giant hypertrophy of the gastric folds that causes protein-losing gastroenteropathy (PLG). Although Menetrier's disease is a known risk factor for gastric adenocarcinoma, the association between Menetrier's disease and malignancy other than a malignancy of the stomach is unclear. A 69-year-old man presented to the Hokkaido Social Work Association Obihiro Hospital with gallbladder tumours diagnosed by ultrasonography at a previous institution. In addition, he had previously been diagnosed with PLG due to Menetrier's disease. Abdominal contrast-enhanced computed tomography (CT) revealed an irregular mass with a contrast effect at the fundus of the gallbladder on the free abdominal cavity side. Positron emission tomography-CT showed a tumour with a standard uptake value (SUV) of 8.28 at the fundus of the gallbladder. Cholecystectomy and resection of the gallbladder bed were performed. Based on the microscopy findings, the patient was diagnosed with ICPN. Although he had postoperative ileus, he was discharged 14 days postoperatively due to improvement through conservative treatment. Such cases of ICPN complicated with Menetrier's disease are extremely rare. However, patients with Menetrier's disease may need to be screened for malignancies.

Mucin-producing Cystic Hepatobiliary Neoplasms: Updated Nomenclature and Clinical, Pathologic, and Imaging Features

Cystic hepatobiliary neoplasms with mucin-producing epithelium-mucinous cystic neoplasm of the liver (MCN) and intraductal papillary neoplasm of the bile duct (IPNB)-are rare and distinct entities that have unique clinical, pathologic, and imaging features. They are differentiated pathologically by the presence of subepithelial ovarian-like hypercellular stroma (OLS), which is the defining histopathologic feature of MCN. MCN is commonly a benign, large, solitary, symptomatic, multiloculated cystic mass without biliary communication that occurs in middle-aged women. On the other hand, IPNBs are a heterogeneous spectrum of tumors, which are commonly associated with invasive carcinoma, occur in older patients, and can be differentiated from MCN by communication with the biliary tree, intraductal masses, associated biliary ductal dilatation, and absent OLS. Understanding of these rare neoplasms has grown and evolved over time and continues to today, but uncertainty and controversy persist, related to the rarity of these tumors, relatively recent designation as separate entities, inherent clinicopathologic heterogeneity, overlapping imaging features, and the fact that many prior studies likely included MCN and cystic IPNB together as a single entity. Confusion regarding these neoplasms is evident by historical inconsistencies and nonstandardized nomenclature through the years. Awareness of these entities is important for the interpreting radiologist to suggest a particular diagnosis or generate a meaningful differential diagnosis in the appropriate setting, and is of particular significance as MCN and cystic IPNB have overlapping imaging features with other more common hepatobiliary cystic masses but have different management and prognosis. Online supplemental material is available for this article. Work of the U.S. Government published under an exclusive license with the RSNA.

Intracystic Papillary Neoplasm of Gallbladder Mimicking Metastatic Malignancy on PET/CT

ABSTRACT

Intracystic papillary neoplasm of the gallbladder is a rare preinvasive neoplastic lesion with similar characteristics as intraductal papillary mucinous neoplasm and other papillary neoplasms of pancreaticobiliary system. We report a case of 48-year-old woman with a history of recurrent right flank chondrosarcoma and gallbladder lesion on MRI and PET/CT interpreted as indeterminate for metastatic disease. Subsequent cholecystectomy showed intracystic papillary neoplasm. With gallbladder lesions being rare on PET/CT, this case illustrates the importance of considering both primary and secondary tumors in the differential diagnosis.

Prognostic implications of the coexisting precursor lesion types in invasive gallbladder cancer

Invasive gallbladder carcinoma (GBC) is preceded by two main types of precursor lesions: intracholecystic papillary-tubular neoplasms (ICPNs) and biliary intraepithelial neoplasias (BilINs). Invasive GBCs with an ICPN component have more favorable prognoses than those without an ICPN component. Some BilINs show a relatively exophytic papillary pattern but do not meet the ICPN criteria; at our institution, we call these papillary neoplasias. To clarify the clinical significance of papillary neoplasia, we herein examined 80 invasive GBCs and classified them into three groups based on the type of preinvasive lesions: those with ICPN (ICPN group, n = 35), those with papillary neoplasia (pap-neoplasia group, n = 13), and those without ICPN/papillary neoplasia (group without ICPN/pap-neoplasia, n = 32). We then compared the prognostic differences and characterized the tumors of each group by determining the immunohistochemical expressions of various biomarkers. The overall survival periods of the ICPN and pap-neoplasia groups were significantly longer than that of the group without ICPN/pap-neoplasia (P < 0.0001, P = 0.0036, respectively). Multivariate analysis revealed that lacking ICPN/papillary neoplasia was independently associated with poor prognosis (P = 0.0007), as were poor differentiation (P = 0.0395), presence of preoperative symptoms (P = 0.0488), and advanced stage (P = 0.0234). Invasive components of the ICPN and pap-neoplasia groups were characterized by higher expressions of p16 and p53 compared with those of the group without ICPN/pap-neoplasia. The prognoses of the invasive GBCs with either papillary neoplasia or ICPN were thus more favorable than those of the invasive GBCs without ICPN/pap-neoplasia. Invasive GBCs with exophytic papillary preinvasive lesions (ICPN and papillary neoplasia) may be biologically different from those without such lesions.

A comparison of outcomes in patients with intracholecystic papillary neoplasms or conventional adenocarcinomas of the gallbladder

BACKGROUND

Intracholecystic papillary neoplasm (ICPN) of the gallbladder (GB) is an exophytic intraepithelial neoplasm. This study aimed to investigate clinicopathologic findings, prognosis and recurrence patterns of patients with ICPN as compared to those patients with conventional adenocarcinoma of the gallbladder (GBC).

METHODS

Patients who underwent surgical resection for suspected GB cancer between 2000 and 2018 were included. ICPN was defined as an exophytic papillary mass within the GB lumen with a size ≥1.0 cm.

RESULTS

Of 607 patients, 241 patients (40%) were pathologically diagnosed with ICPN. Of the 241 patients with ICPNs, 110 (46%) were T1 or less. Following T stage-matched analysis, the rate of lymph node metastases were comparable (50 [52%] vs. 37 [49%], P = 0.581). The five-year survival rate was higher in ICPN, but after T stage-matching, they were comparable (69.1 vs. 63.2%, P = 0.171). Overall recurrence rates were also comparable, with the exception of lower peritoneal seeding in patients with ICPN.

CONCLUSION

Patients with ICPN who underwent resection were more likely to have an earlier T stage. There was no significant difference in prognosis and recurrence between ICPN and conventional GBC after stage matching. Therefore, the treatment strategy for ICPN should follow the same protocols used for conventional GBC.

Current status of diagnosis and therapy for intraductal papillary neoplasm of the bile duct

Bile duct epithelial tumours showing papillary neoplasm in the bile duct lumen are present in the intrahepatic and extrahepatic bile ducts. Clinicopathological images of these tumours are distinctive and diverse, including histological images with a low to high grade dysplasia, infiltrating and noninfiltrating characteristics, excessive mucus production, and similarity to intraductal papillary mucinous neoplasm (IPMN) of the pancreas. The World Health Organization Classification of Tumours of the Digestive System in 2010 named these features, intraductal papillary neoplasm of the bile duct (IPNB), as precancerous lesion of biliary carcinoma. IPNB is currently classified into type 1 that is similar to IPMN, and type 2 that is not similar to IPMN. Many of IPNB spreads superficially, and diagnosis with cholangioscopy is considered mandatory to identify accurate localization and progression. Prognosis of IPNB is said to be better than normal bile duct cancer.

Intraductal papillary neoplasm of the bile duct - A comprehensive review

BACKGROUND

Intraductal papillary neoplasm of the bile ducts is a rare tumor type. Management decisions are currently based upon a small case series. The authors have large own experience with IPNB.

OBJECTIVE

The review aims at reporting on clinicopathological features of IPNB in order to provide guidance for management.

METHODS

We searched PubMed, Medline, Microsoft Academic and Embase databases to identify studies of relevance. The analysis of own experience was also included.

RESULTS

We analyzed 59 retrospective series and 25 cases from authors' clinical experience. The main sign was jaundice and cholangitis, 33% and 48%, respectively. CT's were performed in 63-76% and MR in 40-56%. Intraductal mass was found in 31-32% and duct dilatation in 27-30%. Endoscopic Retrograde Cholangio-Pancreatography (ERCP) was performed in 48-62%. IPNB with invasive carcinoma was found in 35.7-60% and IPNB with intraepithelial neoplasia in 36-60%. Histopathological confirmation before surgery was rare. The main treatment of IPNB is resection, in our material, both, hepatectomy and hepatectomy plus bile duct resections were performed in 40% of patients. The percentage of postoperative complications was 20%. The 5-year survival rate of all IPNB's patients was 53.6%; in patients with associated invasive carcinoma - 22.2% and without invasive carcinoma - 100% (p ​= ​0.001).

CONCLUSIONS

Early surgery is advisable for radiologically suspected IPNB. The results of treatment depend on histopathology. They are worse at intraductal invasive carcinoma than at neoplasm with neoplasia.

Inhibition of FGF10-ERK signal activation suppresses intraductal papillary neoplasm of the bile duct and its associated carcinomas

Evidence regarding intraductal papillary neoplasm of the bile duct (IPNB) as a type of precancerous lesion of cholangiocarcinoma is limited. Moreover, a reproducible in vivo model is lacking, and IPNB pathogenesis remains unclear. Here, we use a doxycycline-inducible tetracycline (Tet)-on mice model to control fibroblast growth factor 10 (FGF10) expression, which regulates branching and tubule formation. FGF10-induced IPNB mimics the multifocal and divergent human IPNB phenotypes via the FGF10-FGF receptor 2 (FGFR2)-RAS-extracellular-signal-regulated kinase (ERK) signaling pathway. A paracrine/autocrine growth factor is sufficient to initiate and maintain IPNB originating from the peribiliary glands, including biliary stem/progenitor cells. With Kras^G12D, p53, or p16 mutations or both, Fgf10-induced IPNB shows stepwise carcinogenesis, causing associated invasive carcinoma. Fgf10-induced papillary changes and progression are suppressed by the inhibition of the FGF10-FGFR2-RAS-ERK signaling pathway, demonstrating that the signal is a therapeutic target for IPNB and associated carcinoma.

Intraductal Papillary Neoplasm of the Bile Duct: A Rare Case of Intrahepatic Space-Occupying Lesion

Intraductal papillary neoplasm of the bile duct (IPNB) is a rare tumor and is considered one of the precursor lesions for cholangiocarcinoma. Though relatively common in the far east countries, it is uncommon in the Indian population. A 67-year-old gentleman presented with vague upper abdominal pain with no history of fever, jaundice, melena, or hematemesis. An abdominal ultrasound showed a solid cystic lesion in the left lobe of the liver with upstream dilatation of bile ducts. Computed tomography and magnetic resonance imaging showed similar findings. With a differential diagnosis of intrahepatic cholangiocarcinoma, intraductal papillary neoplasm, and biliary cystadenoma, he underwent robotic-assisted left hepatectomy. Histopathology was suggestive of IPNB. Following surgery, he had an uneventful recovery and was advised for follow-up visits every six months. A clinical, radiological, and pathological profile of this rare tumor has been described here with a review of the existing literature.

Reappraisal of pathological features of intraductal papillary neoplasm of bile duct with respect to the type 1 and 2 subclassifications

The pathological spectrum of intraductal papillary neoplasm of bile duct (IPNB) remains to be clarified. A total of 186 IPNBs were pathologically examined using the type 1 and 2 subclassifications proposed by Japanese and Korean biliary pathologists incorporating a two-tiered grading system (low-grade and high-grade dysplasia), with reference to four subtypes (intestinal [i], gastric [g], pancreatobiliary [pb], and concocytic [o] subtype). IPNBs were classifiable into type 1 composed of low-grade dysplasia and 'high-grade dysplasia with regular structures' (69 IPNBs), and type 2 of 'high grade dysplasia with irregular structures and complicated lesions' (117 IPNBs). Type 1 was more common in the intrahepatic bile duct (78%), whereas type 2 was frequently located in the extrahepatic bile duct (58%). Mucin hypersecretion was more common in type 1 (61%) than in type 2 (37%). IPNBs were classifiable into the four subtypes: 86 iPNBs, 40 gIPNBs, 31 pbIPNBs, and 29 oIPNBs. The four subtypes were histologically evaluable with reference to the type 1 and 2 subclassifications. iIPNB and pbIPNBs were frequently classified as type 2, whereas types 1 and 2 were observed at similar rates in gIPNB and oIPNB. Stromal invasion was almost absent in type 1, irrespective of subtype, but was found in 66 of 117 type 2 IPNBs (P < .01), and postoperative outcome was favorable in IPNBs without invasion compared with IPNBs with invasion (P < .05). The type 1 and 2 subclassifications with reference to the four subtypes may provide useful information for understanding IPNB.

Intraductal papillary mucinous neoplasm of the biliary tract with cardiac metastasis: A case report

INTRODUCTION

Intraductal papillary mucinous neoplasm of the biliary tract (IPNB) is a rare, low-grade neoplasm limited to the bile duct mucosa. The malignant transformation rate is low, and there have been limited reports of metastasis to other organs. Herein, we presented a rare case of a patient who was diagnosed with IPNB concurrent with invasive adenocarcinoma after surgery and was diagnosed with cardiac metastasis 6 months later.

PATIENT CONCERNS

A 61-year-old male patient presented with abdominal pain to a local clinic. He was diagnosed with intrahepatic cholangiocarcinoma with pancreatitis and transferred to our hospital.

DIAGNOSIS

Diagnostic testing (magnetic resonance imaging, endoscopic retrograde cholangiopancreatography, positron emission tomography-computed tomography) revealed a papillary neoplasm and invasive adenocarcinoma with papillary neoplasm in the periampullary lesion.

INTERVENTIONS

Pancreaticoduodenectomy, right hemihepatectomy, and left lateral sectionectomy of the liver were performed. After surgery, we planned gemcitabine-based adjuvant chemotherapy.

OUTCOMES

Upon completion of the sixth gemcitabine chemotherapy cycle, a hyperechoic, oval-shaped mass (1.3 × 2.6 cm) was found on the outer wall of the right atrium. Resection of a cardiac tumor in the right atrium and patch repair were performed.

CONCLUSION

To our knowledge, no other case of cardiac metastasis found during observation after surgery for an IPNB has been described. IPNBs are known to be less aggressive and to have a lower metastasis rate than intraductal papillary mucinous neoplasms; therefore, the number of case reports describing metastasis after surgery is relatively low. Our case suggests that close observation is necessary in patients diagnosed with an IPNB.

Intrahepatic Biliary Intraductal Papillary Mucinous Neoplasm With Intermittent Jaundice: Case Report

Intraductal papillary mucinous neoplasms (IPMNs) represent a relatively new clinical entity. IPMNs have malignant potential which exhibit a broad histological spectrum, ranging from adenoma to invasive carcinoma. Although IPMNs are commonly seen within pancreas, they may develop anywhere within the biliary ductal system and produce mucin which may cause intermittent jaundice. This report details the case of 50-year-old woman presenting with intermittent jaundice who was diagnosed as hepatic IPMN.

Cystic biliary tumors of the liver: diagnostic criteria and common pitfalls

With major advancements and frequent use of abdominal imaging techniques, hepatic cysts are increasingly encountered in clinical practice. Although the majority of cysts are benign, a small subset represents neoplastic precursors to cholangiocarcinoma. These cystic precursors include intraductal papillary neoplasms of the bile duct (IPNB) and mucinous cystic neoplasms of the liver (MCN-L), and bear striking pathologic resemblance to corresponding cystic neoplastic precursors within the pancreas. This review examines the salient clinical, gross, microscopic and molecular features of IPNBs and MCN-Ls, and, in particular, provides histopathologic comparison to their pancreatic counterparts. Considering these neoplasms may be diagnostically challenging, we also discuss other hepatic lesions within the differential diagnosis, and the potential for molecular methods to improve their preoperative evaluation and the early detection of cholangiocarcinoma.

Intrahepatic cholangiocarcinoma: Morpho-molecular pathology, tumor reactive microenvironment, and malignant progression

Intrahepatic cholangiocarcinoma (iCCA) is a relatively rare, but highly lethal and biologically complex primary biliary epithelial cancer arising within liver. After hepatocellular carcinoma, iCCA is the second most common primary liver cancer, accounting for approximately 10-20% of all primary hepatic malignancies. Over the last 10-20 years, iCCA has become the focus of increasing concern largely due to its rising incidence and high mortality rates in various parts of the world, including the United States. The challenges posed by iCCA are daunting and despite recent progress in the standard of care and management options for iCCA, the prognosis for this cancer continues to be dismal. In an effort to provide a framework for advancing our understanding of iCCA malignant aggressiveness and therapy resistance, this review will highlight key etiological, biological, molecular, and microenvironmental factors hindering more effective management of this hepatobiliary cancer. Particular focus will be on critically reviewing the cell origins and morpho-molecular heterogeneity of iCCAs, providing mechanistic insights into high risk fibroinflammatory cholangiopathies associated with iCCA development, and notably discussing the deleterious role played by the tumor reactive desmoplastic stroma in regulating iCCA malignant progression, lymphangiogenesis, and tumor immunobiology.