Intraductal papillary neoplasm of the bile duct with metachronous development in the downstream bile duct after radical resection.

We report a case of intraductal papillary neoplasms of the bile duct (IPNB) that metachronously developed twice in the downstream bile duct after radical resection. The first lesion was located in the left intrahepatic bile duct, the second lesion in the perihilar bile duct, and the third lesion in the distal bile duct. All lesions were IPNBs with associated invasive carcinoma (pancreatobiliary type). The depth of invasion was to the Glisson's capsule in the first lesion, to the subserosa in the second lesion, and to the fibromuscular layer in the third lesion, without lympho-vascular/perineural invasion and lymph-node metastasis. These were resected radically and had no biliary intraepithelial neoplasia and hyperplasia in the surrounding mucosa. In immunohistochemical examination, each lesion showed a different pattern. Although the downstream occurrence suggests intrabiliary dissemination, the mechanism of these metachronous developments may be multicentric. A literature review revealed that most metachronous cholangiocarcinomas have a grossly papillary appearance and tend to arise downstream. Our findings suggest that IPNB may develop metachronously in the residual bile duct after radical surgery, which may assist in early detection.

Establishment of Patient-derived Preclinical Models for Invasive Papillary Cholangiocarcinoma.

BACKGROUND/AIM: Invasive papillary cholangio-carcinoma (IPC) is a minor subtype of extrahepatic cholangiocarcinoma. However, its etiology and characteristics remain unknown because of the unavailability of in vitro and in vivo models. We aimed to establish a novel preclinical model for translational research of IPC. MATERIALS AND METHODS: A patient-derived xenograft (PDX) was engrafted in NOG mice and the cell line National Cancer Center human IPC (NCChIPC) was subsequently established from the PDX tumors. Immunohistochemistry and RNA-sequencing were used to determine the retention of original characteristics of patient tissues. RESULTS: PDX tumors showed successful amplification, and the NCChIPC-derived xenograft largely retained the histopathological features of the original tumor with CK19, MUC1 and MUC5AC expression. Transcriptome analysis showed a high correlation between patient and preclinical models. Additionally, anticancer drugs response was analyzed in the NCChIPC PDX. CONCLUSION: These novel preclinical models here will help elucidate IPC etiology and facilitate translational research.

Biliary intraductal tubule-forming neoplasm: a whole exome sequencing study of MUC5AC-positive and -negative cases.

AIMS: Biliary intraductal tubular neoplasms that are non-mucinous and negative for mucin 5AC (MUC5AC) are called intraductal tubulopapillary neoplasms (ITPNs). Intraductal tubular neoplasms with mucinous cytoplasm and MUC5AC positivity also occur and their nature remains unclear, although some pathologists may classify these as 'intraductal papillary neoplasms of the bile duct (IPNBs) of gastric type'. This study aimed to elucidate genetic features of biliary intraductal tubular neoplasms. METHODS AND RESULTS: Six resected cases of biliary intraductal neoplasm with >70% tubular configuration were characterised by clinicopathological examination and whole exome sequencing, and the findings obtained were compared between MUC5AC-negative (n = 2) and -positive cases (n = 4). The intraductal tumours consisted of the pancreatobiliary-type epithelium with high-grade dysplasia arranged in back-to-back tubules. Both of the two MUC5AC-negative cases were non-invasive neoplasms and developed in the liver, whereas all MUC5AC-positive cases had invasive carcinoma and were present in the intrahepatic (n = 2), perihilar (n = 1) and distal bile ducts (n = 1). In an exome-sequencing study, MUC5AC-negative cases harboured mutations in CTNNB1, SF3B1, BAP1 and BRCA1 (one case each). KRAS mutations were observed in three of four MUC5AC-positive cases (75%) but none of the MUC5AC-negative neoplasms. Compared to published data, known driver genes of other intraductal neoplasms of the pancreatobiliary system (e.g. APC, CTNNB1, STK11, GNAS and PIK3CA) were wild-type in all but one MUC5AC-negative case with CTNNB1 mutation. Chromatin modifiers (ARID1A, BAP1 and KMT2C) were also altered in MUC5AC-positive cases, similar to usual cholangiocarcinomas. CONCLUSIONS: This exome-sequencing study suggested that MUC5AC-negative biliary ITPNs are genetically distinct from pancreatic ITPNs and IPNBs. They may also biologically differ from MUC5AC-positive tubular neoplasms despite morphological resemblance.

Usefulness of Preoperative 18F-FDG-PET in Detecting Invasive Intraductal Papillary Neoplasm of the Bile Duct.

BACKGROUND/AIM: Preoperative identification of the invasive component remains challenging in intraductal papillary neoplasm of the bile duct (IPNB). We evaluated the ability of preoperative 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) to differentiate between non-invasive IPNB, invasive IPNB, and papillary cholangiocarcinoma (CCA). PATIENTS AND METHODS: The maximum standardized uptake values (SUVmax) of 11 patients with IPNB (6 non-invasive and 5 invasive) and 20 with papillary CCA who underwent pre-surgical 18F-FDG-PET were assessed. The SUVmax cut-off that predicts an invasive component was determined using receiver operating characteristic (ROC) curve analysis. RESULTS: The SUVmax in patients with invasive IPNB and papillary CCA were significantly higher than in patients with non-invasive IPNB (p=0.035 and 0.0025, respectively). ROC curve analysis revealed an optimal SUVmax cut-off of 4.5, which had 94.5% accuracy, 76.0% sensitivity, and 100% specificity. CONCLUSION: Our data suggest that the preoperative 18F-FDG-PET SUVmax can differentiate non-invasive IPNB from invasive IPNB and papillary CCA.

A statement by the Japan-Korea expert pathologists for future clinicopathological and molecular analyses toward consensus building of intraductal papillary neoplasm of the bile duct through several opinions at the present stage.

Intraductal papillary neoplasm of bile duct (IPNB) was described as a preinvasive neoplastic lesion of the biliary tract in the 2010 World Health Organization (WHO) classification. Although a number of studies have since been conducted on IPNBs, controversy remains, particularly regarding the standardization of its definition. Meetings by Japanese and Korean expert pathologists were held twice to resolve the pathological diagnostic aspects of IPNB. Through round-table discussions and histological reviews, we reached the common understanding that IPNBs diagnosed according to the criteria of WHO 2010 are characterized by intraductal predominant papillary or villous biliary neoplasms covering delicate fibrovascular stalks and are classified into two types pathologically. One type (type 1 IPNB) is histologically similar to intraductal papillary mucinous neoplasms of pancreas, and typically develops in the intrahepatic bile ducts, while the other (type 2 IPNB) has a more complex histological architecture with irregular papillary branching or with foci of solid-tubular components and typically involves the extrahepatic bile ducts. This report states the diagnostic pathologic features of IPNB proposed by WHO 2010. Since currently, the concept of IPNB is still confusing, the proposed diagnostic pathologic features stated here will be of use for future clinicopathological and molecular analyses toward consensus building of IPNB.

Poorly differentiated adenocarcinoma with signet-ring cells in duodenal papilla: a case report.

An 82-year-old woman with common bile duct (CBD) dilatation observed during routine ultrasonography was referred to our hospital. Preliminary blood tests revealed elevated levels of hepatobiliary enzymes. Computed tomography (CT) scan showed lower bile duct wall thickening and enhancement. Esophagogastroduodenoscopy revealed mildly swollen papilla of Vater, without ulceration. Endoscopic retrograde cholangiography demonstrated that the CBD was grossly dilated with a constriction in the lower part. The final diagnosis indicated poorly differentiated adenocarcinoma of duodenal papilla with signet-ring cells; pT3N0M0, stage IIA (Unio Internationalis Contra Cancrum, 7th edition), for which subtotal stomach-preserving pancreaticoduodenectomy (SSPPD) was performed. This case is quite rare, and the surgery resulted in a desirable outcome. The patient has been disease-free for 5 years since the surgery.

Pathological characteristics of intraductal polypoid neoplasms of bile ducts in Thailand.

Intraductal papillary or tubular neoplasms of the bile duct have recently been proposed as one of the pre-invasive lesions of cholangiocarcinoma. Herein, a total of 50 cases of intraluminal polypoid neoplasms of the bile ducts experienced in Khon Kaen University Hospital in Thailand were pathologically examined. These cases presumably had a history of infection of Opisthorchis viverrini. These neoplasms were histologically composed of high-grade intraepithelial neoplasm showing a tubular and/papillary pattern without invasion (20 cases), and with minimal and considerable invasion (15 and 15 cases, respectively). They were histologically classifiable into papillary type (10 cases), tubular type (20 cases) and papillotubular type (20 cases), and were phenotypically classifiable into gastric (17 cases), intestinal (17 cases) and pancreatobiliary types (16 cases). It was found that cases of papillary type and gastric or intestinal phenotype were less invasive, while those of tubular or papillotubular type and pancreatobiliary phenotype were more invasive. In conclusion, intraductal polypoid neoplasms in Thailand were well-differentiated papillary and/or tubular neoplasms including those with no or minimal invasion, and histological and phenotypic subclassifications seem to be useful for evaluation of the aggressive pathological behaviors of these neoplasms.

Clinicopathological characterization of so-called "cholangiocarcinoma with intraductal papillary growth" with respect to "intraductal papillary neoplasm of bile duct (IPNB)".

Cholangiocarcinoma (CC) of the biliary tract occasionally presents a predominant intraductal papillary growth in the bile ducts, called as biliary tract carcinoma (BTC) of papillary growth (PG) and intrahepatic CC (ICC) of intraductal growth (IG) type. Recently, intraductal papillary neoplasm of bile duct (IPNB) has been proposed as a pre-invasive biliary neoplasm. This study was performed to characterize pathologically BTC of PG type and ICC of IG type with respect to IPNB. It was found that 126 of such 154 CCs (81.8%) fulfilled the criteria of IPNB, while the remaining 28 cases showed different histologies, such as tubular adenocarcinoma and carcinosarcoma. These IPNBs occurred in old aged patients with a male predominance, and the left lobe was rather frequently affected in the liver. A majority of these cases were high grade IPNB (43 cases) and invasive IPNB (77 cases), while low grade IPNB was rare (6 cases). Pancreatobiliary type was predominant (48 cases) followed by gastric (30 cases), intestinal (29 cases) and oncocytic (19 cases) types. Mucus hypersecretion was found in 45 cases, and this was frequent in IPNB at the intrahepatic large bile duct and hilar bile ducts but rare at the extrahepatic bile ducts. Interestingly, 36 cases of high grade and invasive IPNBs contained foci of moderately differentiated adenocacinoma within the intraductal papillary tumor. In conclusion, a majority of ICC of IG type and BTC of PG type could be regarded as a IPNB lineage, and clinically detectable IPNBs were already a malignant papillary lesion.

Intraductal papillary neoplasm of the bile duct.

Intraductal papillary neoplasm of the bile duct (IPNB) is a variant of bile duct carcinoma that is characterized by intraductal growth and better outcomes compared with common cholangiocarcinoma. IPNBs are mainly found in patients from Far Eastern areas, where hepatolithiasis and clonorchiasis are endemic. According to the immunohistochemical profiles of the mucin core proteins, IPNBs are classified into four types: pancreaticobiliary, intestinal, gastric, and oncocytic. Approximately 40%-80% of IPNBs contain a component of invasive carcinoma or tubular or mucinous adenocarcinoma, suggesting that IPNB is a disease with high potential for malignancy. It is difficult to make an accurate preoperative diagnosis because of IPNB's low incidence and the lack of specificity in its clinical manifestation. The most common abnormal preoperative imaging findings of IPNB are intraductal masses and the involvement of bile duct dilation. Simultaneous proximal and distal bile duct dilation can be detected in some cases, which has diagnostic significance. Cholangiography and cholangioscopy are needed to confirm the pathology and demonstrate the extent of the lesions. However, pathologic diagnosis by biopsy cannot reflect the actual stage in many cases because different foci may be of different stages and because mixed pathologic findings may exist in the same lesion. Surgical resection is the major treatment. Systematic cholangioscopy with staged biopsies and frozen sections is recommended during resection to ensure that no minor tumors are left and that curative resection is achieved. Staging, histologic subtype, curative resection and lymph node metastasis are factors affecting long-term survival.