Biliary papillary tumors share pathological features with intraductal papillary mucinous neoplasm of the pancreas

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.

Bile acids increase levels of microRNAs 221 and 222, leading to degradation of CDX2 during esophageal carcinogenesis

BACKGROUND & AIMS

Bile reflux contributes to development of Barrett's esophagus (BE) and could be involved in its progression to esophageal adenocarcinoma (EAC). We investigated whether bile acids affect levels or functions of microRNAs (MIRs) 221 and 222, which bind to the 3'-UTR of p27Kip1 messenger RNA to inhibit its translation. Reduced p27Kip1 increases degradation of the transcription factor CDX2; levels of CDX2 have been reported to decrease during progression of BE to EAC.

METHODS

We used quantitative reverse transcriptase polymerase chain reaction to compare levels of MIRs 221 and 222 and immunohistochemistry to compare levels of p27Kip1 and CDX2 proteins in areas of BE and EAC from each of 11 patients. We examined the effects of bile acid exposure on levels of MIRs 221 and 222 and CDX2 in EAC cells. We investigated the effects of inhibitors of MIRs 221 and 222 on growth of human EAC xenograft tumors in NOD/SCID/IL-2Rγ(null) mice.

RESULTS

Levels of MIRs 221 and 222 increased and levels of p27Kip1 and CDX2 decreased in areas of EAC vs BE. Levels of MIRs 221 and 222 increased, along with activity of nuclear bile acid receptor/farnesoid X receptor (FXR), when cultured cells were exposed to bile acids. Incubation of cells with bile acids increased degradation of CDX2; this process was reduced when cells were also incubated with proteasome inhibitors. Overexpression of MIRs 221 and 222 reduced levels of p27Kip1 and CDX2, and knockdown of these MIRs increased levels of these proteins in cultured cells. Inhibitors of MIRs 221 and 222 increased levels of p27Kip1 and CDX2 in EAC cells and reduced growth of xenograft tumors in NOD/SCID/IL-2Rγ(null) mice.

CONCLUSIONS

We observed increased levels of MIRs 221 and 222 in human EAC tissues, compared with areas of BE from the same patient. We found that exposure of esophageal cells to bile acids activates FXR and increases levels of MIRs 221 and 222, reducing levels of p27Kip1 and promoting degradation of CDX2 by the proteasome. Our work opened the perspective of therapeutically targeting this pathway either via FXR antagonists or inhibitors of MIRs as a treatment option for BE and EAC.

Prognostic delineation of papillary cholangiocarcinoma based on the invasive proportion: a single-institution study with 184 patients

BACKGROUND

Intraductal papillary neoplasm of the bile duct (IPNB) is a presumed precursor lesion in biliary carcinogenesis, clinicopathologically overlapping with papillary cholangiocarcinomas (PCC); however, because IPNB has no standardized definition, this relationship remains equivocal. Herein, we aimed to develop a new prognostic model for PCC by focusing on the invasive proportion.

METHODS

Among 644 patients with resected cholangiocarcinoma (1998-2011), 184 (28%) had intraductal, exophytic, papillary lesions. These were divided into 4 subsets based on the invasive component: Noninvasive (PCC-1; n = 14), ≤10% (PCC-2; n = 32), 11-50% (PCC-3; n = 60), and >50% (PCC-4; n = 78). The remaining 460 were identified as non-PCCs (NPCC).

RESULTS

Invasion beyond the duct wall and regional lymph node metastases were more frequent in NPCC than PCC (P < .001 for both). Five-year survival was better for PCC (55%) than NPCC (35%; P < .001), indicating the papillary component to be a significant, independent prognosticator. PCC-4 and NPCC had similar clinicopathologic features and overlapping survival curves: 33% and 35% at 5 years (P = .835), both less than those of PCC-1, PCC-2, and PCC-3 (respectively, 92%, 74%, and 64% at 5 years; P < .005 in all combinations). Multivariate analysis in PCC showed >50% invasive component, nodal metastasis, and a positive operative margin as independent predictors.

CONCLUSION

PCC survival decreased with progression of the invasive component. PCC with >50% invasive component was clinicopathologically similar to NPCC. Although IPNB might be nosologically applied only for PCC cases with ≤50% invasive component, the present prognostic delineation suggests that all PCC subgroups belonged to a singular disease group.

Metachronous intracystic and intraductal papillary neoplasms of the biliary tree

A 77-year-old woman complained of epigastralgia, and a tumor (5 cm in diameter) of the gallbladder neck was detected by image analysis. Following cholecystectomy, the tumor was pathologically diagnosed as intraductal papillary neoplasm (IPN), gastric type, with associated invasive carcinoma. About 10 mo later, intraluminal multiple masses (3 foci, up to 1.8 cm) were noted in the extrahepatic bile duct, and the resected specimen showed that all tumors had similar gross and microscopic features as seen in gallbladder IPN without invasion, and they were synchronous multiple lesions. This case showed a papillary tumor of the gallbladder of gastric phenotype, and confirmed that the gallbladder is a target of IPN in addition to the bile ducts.

Participation of peribiliary glands in biliary tract pathophysiologies

AIM: To investigate the roles of peribiliary glands around the bile ducts in the pathophysiology of the biliary tract.

METHODS: The expression of fetal pancreatic markers, pancreatic duodenal homeobox factor 1 (PDX1) and hairy and enhancer of split 1 (HES1) and endodermal stem/progenitor (S/P) cell markers [CD44s, chemokine receptor type 4 (CXCR4), SOX9 and epithelial cell adhesion molecule (EpCAM)] were examined immunohistochemically in 32 normal adult livers (autopsy livers) and 22 hepatolithiatic livers (surgically resected livers). The latter was characterized by the proliferation of the peribiliary glands. Immunohistochemistry was performed using formalin-fixed, paraffin-embedded tissue sections after deparaffinization. Although PDX1 and HES1 were expressed in both the nucleus and cytoplasm of epithelial cells, only nuclear staining was evaluated. SOX9 was expressed in the nucleus, while CD44s, CXCR4 and EpCAM were expressed in the cell membranes. The frequency and extent of the expression of these molecules in the lining epithelia and peribiliary glands were evaluated semi-quantitatively based on the percentage of positive cells: 0, 1+ (focal), 2+ (moderate) and 3+ (extensive).

RESULTS: In normal livers, PDX1 was infrequently expressed in the lining epithelia, but was frequently expressed in the peribiliary glands. In contrast, HES1 was frequently expressed in the lining epithelia, but its expression in the peribiliary glands was focal, suggesting that the peribiliary glands retain the potential of differentiation toward the pancreas and the lining epithelia exhibit properties to inhibit such differentiation. This unique combination was also seen in hepatolithiatic livers. The expression of endodermal S/P cell markers varied in the peribiliary glands in normal livers: SOX9 and EpCAM were frequently expressed, CD44s infrequently, and CXCR4 almost not at all. The expression of these markers, particularly CD44s and CXCR4, increased in the peribiliary glands and lining epithelia in hepatolithiatic livers. This increased expression of endodermal S/P cell markers may be related to the increased production of intestinal and gastric mucin and also to the biliary neoplasia associated with the gastric and intestinal phenotypes reported in hepatolithiasis.

CONCLUSION: The unique expression pattern of PDX1 and HES1 and increased expression of endodermal S/P cell markers in the peribiliary glands may be involved in biliary pathophysiologies.

Proposal for a morphological classification of intraductal papillary neoplasm of the bile duct (IPN-B)

PURPOSE

We propose a morphological classification of intraductal papillary neoplasm of the bile duct (IPN-B).

METHODS

A retrospective analysis of 16 patients with IPN-B who had undergone surgical resection was conducted. These 16 cases were classified into three types based on the primary lesion's anatomical location: branch duct type (6 cases), main duct type (5 cases) and mixed type (5 cases). In this paper we have analyzed the characteristics of IPN-B according to our new classification.

RESULTS

All branch duct type IPN-B was located in the left lobe and 5 of them were resected by left hepatectomy without extrahepatic bile duct resection (EBDR). On the other hand, all patients with main duct and mixed type IPN-B underwent EBDR in addition to hepatectomy or pancreatoduodenectomy. Microscopically, 2 of 6 patients with branch duct type IPN-B had no malignant component and, in the remaining 4 patients, cancer invasion was restricted to within the ductal wall. There were no cases of branch duct type IPN-B with lymph node metastasis and superficial intraductal tumor spread. In contrast, all patients with main duct and mixed duct type IPN-B had the malignant component. In all cases, lymph node metastasis was not observed, but superficial intraductal tumor spread was frequently found in extrahepatic bile duct lesions: 3 of main duct type and 3 of mixed type. Four patients with superficial intraductal spread had non-curative resection due to a cancer-positive ductal margin. Most patients with IPN-B obtained a good prognosis, but two patients with a cancer-positive ductal margin developed local recurrence.

CONCLUSIONS

Our classification vividly reflects clinical and pathological characteristics of IPN-B and is useful to determine appropriate surgical strategy.

Clinicopathological features and prognosis of mucin-producing bile duct tumor and mucinous cystic tumor of the liver: a multi-institutional study by the Japan Biliary Association

BACKGROUND

The aim of this study was to determine the clinicopathological features and surgical outcomes of mucinous cystic neoplasm of the liver (MCN) and mucin-producing intraductal papillary neoplasm of the intrahepatic bile duct (M-IPNB).

METHODS

We performed a multi-institutional, retrospective study of patients with MCN or M-IPNB pathologically defined by the presence or absence of an ovarian-like stroma.

RESULTS

The M-IPNB and MCN were diagnosed in 119 and nine patients, respectively. MCN was observed in female patients, while M-IPNB produced symptoms of cholangitis. M-IPNBs were classed as low or intermediate grade in 53 cases, high grade in 23 and invasive carcinoma in 43. Fifty-one of the M-IPNBs were the pancreatobiliary type (PT), 33 were the intestinal type (IT), 23 were the oncocytic type (OT), and 12 were the gastric type (GT). The 1-, 5- and 10-year survival rates for the 105 patients with M-IPNB were 96%, 84% and 81%, respectively, while the 5-year survival rate for patients with MCN was 100%. OT and GT M-IPNB had better 10-year survival rates than PT and IT M-IPNB.

CONCLUSIONS

Although MCN has different features from M-IPNB, both diseases have a good prognosis after resection. The cellular type of M-IPNB appears to predict outcome.

Pathological aspects of so called "hilar cholangiocarcinoma"

Cholangiocarcinoma (CC) arising from the large intrahepatic bile ducts and extrahepatic hilar bile ducts share clinicopathological features and have been called hilar and perihilar CC as a group. However, “hilar and perihilar CC” are also used to refer exclusively to the intrahepatic hilar type CC or, more commonly, the extrahepatic hilar CC. Grossly, a major distinction can be made between papillary and non-papillary tumors. Histologically, most hilar CCs are well to moderately differentiated conventional type (biliary) carcinomas. Immunohistochemically, CK7, CK20, CEA and MUC1 are normally expressed, being MUC2 positive in less than 50% of cases. Two main premalignant lesions are known: biliary intraepithelial neoplasia (BilIN) and intraductal papillary neoplasm of the biliary tract (IPNB). IPNB includes the lesions previously named biliary papillomatosis and papillary carcinoma. A series of 29 resected hilar CC from our archives is reviewed. Most (82.8%) were conventional type adenocarcinomas, mostly well to moderately differentiated, although with a broad morphological spectrum; three cases exhibited a poorly differentiated cell component resembling signet ring cells. IPNB was observed in 5 (17.2%), four of them with an associated invasive carcinoma. A clear cell type carcinoma, an adenosquamous carcinoma and two gastric foveolar type carcinomas were observed.

Clinicopathologic analysis of undifferentiated carcinoma of the gallbladder

BACKGROUND

Undifferentiated carcinoma (UC) of the gallbladder (GB) is a rare malignant neoplasm and there have only been sparse case reports without precise description. We analyzed eight cases of UC of GB and compared with gallbladder carcinoma (GBC) in the aspects of clinicopathologic characteristics and prognosis.

METHODS

We found eight UC cases out of 238 surgically resected GBCs. Patients with stage-matched GBC were selected (1:4) for comparative analysis of the clinicopathologic features and survival of UC.

RESULTS

Histologically, UC cases were composed of four sarcomatoid, two pleomorphic, one small cell, and one osteoclast-like giant cell types. There was no difference between UC and ordinary GBC in clinicopathologic parameters, except for tumor size. It was significantly larger in UC (median; 5.0 cm, ranging 1.3-10.0 cm) compared to GBC (median; 3.0 cm, ranging 1.5-9.0 cm, P = 0.01). UC presented frequent intraluminal polypoid mass (87.5%: 7/8). UC showed significantly poor overall survival rate (37.5%, 37.5% and 18.8% at 1, 3, and 5 years), than GBC (84.4%, 65.6% and 52.1%, respectively) (P = 0.005). Pathologic findings of UC were an independent prognostic factor for poor survival in GBC (HR 7.242, 95% confidence interval: 1.799-29.147).

CONCLUSIONS

Undifferentiated carcinoma of the gallbladder was a rare highly malignant neoplasm and frequently presented a large intraluminal polypoid tumor. It showed a significantly larger tumor size and poorer survival than GBC.

An intraductal papillary neoplasm of the bile duct mimicking a hemorrhagic hepatic cyst: a case report

An intraductal papillary neoplasm of the bile duct is a biliary, epithelium-lined, cystic lesion that exhibits papillary proliferation and rarely causes large hemorrhagic cystic lesions. Here, we report a case of an intraductal papillary neoplasm of the bile duct mimicking a hemorrhagic hepatic cyst in a middle-aged man with large hemorrhagic hepatic cysts who experienced abdominal pain and repeated episodes of intracystic bleeding. Following portal vein embolization, extended right hepatic lobectomy was performed, and intraoperative cholangiography revealed communication between the intracystic space and the hepatic duct. Although histological studies revealed that the large hemorrhagic lesion was not lined with epithelium, the surrounding multilocular lesions contained biliary-derived epithelial cells that presented as papillary growths without ovarian-like stroma. A diagnosis of oncocytic-type intraductal papillary neoplasm of the bile duct was made, and we hypothesized that intracystic bleeding with denudation of the lining epithelial cells might occur as the cystically dilated bile duct increased in size. Differential diagnosis between a hemorrhagic cyst and a cyst-forming intraductal papillary neoplasm of the bile duct with bleeding is difficult. However, an intraductal papillary neoplasm of the bile duct could manifest as multilocular hemorrhagic lesions; therefore, complete resection should be performed for a better prognosis.

Impact of macroscopic morphology, multifocality, and mucin secretion on survival outcome of intraductal papillary neoplasm of the bile duct

BACKGROUND

Intraductal papillary neoplasms of the bile duct (IPNB) are relatively rare disease with favorable prognosis. The authors investigated clinicopathologic characteristics and prognostic factors of IPNB in viewpoint of macroscopic morphology and multiplicity.

METHODS

Data were collected from 84 patients who underwent surgery at Seoul National University Hospital with diagnosis of IPNB from 2000 to 2009.

RESULTS

Median follow-up was 41.8 months and 75 (89.3 %) had invasive cancer. Tumors were confined to the bile duct in 45 patients (53.6 %) and 8 (9.5 %) had lymph node metastasis. Curative resection was achieved in 70 patients (89.3 %). Mucin secretion was identified in 23 (28.0 %) and 43 (51.2 %) had multiple tumors. Multiple IPNB had poor prognosis compared with single IPNB (5-year survival rate 50.7 vs. 85.9 %; P = 0.011). Positive resection margin (P = 0.046) and multiplicity (P = 0.038) were independent prognostic factors of IPNB after multivariate analysis. Mucin secretion had no impact on survival outcome (P = 0.595). The disease-free survival rate was significantly lower in multiple IPNB compared with single IPNB (5-year disease free survival rates 36.1 vs. 74.1 %; P = 0.026).

CONCLUSION

Multiplicity is a common feature of IPNB and has a negative impact on prognosis. Current WHO classification for IPNB needs consideration for macroscopic morphology and multiplicity considering its prognostic impact of IPNB.

Clinicopathological subclassification of biliary cystic tumors: Report of 4 cases with a review of the literature

Biliary cystic tumors are rare hepatic neoplasms, and knowledge regarding the origin and pathology of these tumors remains vague. They should be analyzed in more detail. In our institution, 4 biliary cystic tumor surgeries were performed between December 1999 and March 2010. Pathological evaluation of resected specimens was performed to evaluate the characteristics of the intracystic epithelium and to determine the presence or absence of interstitial infiltrate, ovarian mesenchymal stroma (OMS), luminal communication between the cystic tumor and the bile duct, and mucin (MUC) protein expression. We evaluated the following 4 cases: case 1, a 21-year-old woman with a biliary cystadenoma who underwent extended right hepatectomy; case 2, a 39-year-old woman with a biliary cystadenoma who underwent left hepatectomy; case 3, an 80-year-old man with a biliary cystadenoma who underwent left hepatectomy; and case 4, a 61-year-old man with a biliary cystadenocarcinoma revealing papillary proliferation of atypical epithelium and interstitial infiltrates who underwent left hepatectomy. Case 3 had papillary proliferation of the intracystic atypical epithelium but showed interstitial infiltrates. Luminal communication with the bile duct, centrally or peripherally, was found in all 4 cases. Only case 2 showed OMS. Immunohistochemical staining revealed the following findings: cases 1 and 2, MUC1-/MUC2-; case 3, MUC1+/MUC2-; and case 4, MUC1+/MUC2+. It is important to gather information on more cases of biliary cystic tumors because atypical cases were observed, where both OMS and luminal communication with the bile duct were present or absent.

Intrahepatic biliary intraductal papillary mucinous neoplasm with gallbladder agenesis: case report

We report here on a case of intraductal papillary mucinous neoplasm (IPMN) of the bile duct, associated with gallbladder agenesis. A 65-year-old woman was admitted to the hospital with epigastric pain, anorexia, and nausea. Abdominal computed tomography scan and magnetic resonance imaging showed a 5 × 2.5 cm lobulated cystic lesion in the lateral lobe of the liver. The gallbladder was not seen on both imaging modalities. Endoscopic retrograde cholangiopancreatography suggested the diagnosis of biliary IPMN due to abundant mucin that protruded from the papilla and the lobulated cystic lesion. Laparoscopic wedge resection of the liver was performed. The final pathology was consistent with biliary IPMN. The specimen showed multifocal high-grade dysplasia with negative resection margins. The patient experienced no postoperative complications and was discharged 5 days after the operation.

Precancerous lesions of the biliary tree

The neoplasms of the biliary tree include the carcinomas of the intra- and extrahepatic bile ducts, the gallbladder and the ampulla. Two types of precancerous lesions precede these adenocarcinomas: the flat and non-tumour forming type that is called biliary intraepithelial neoplasia, and the papillary and tumour-forming type that has been named intraductal papillary neoplasm of the bile duct. Rarely also biliary mucinous cystic neoplasm can give rise to invasive biliary adenocarcinomas. This review discusses the pathological, molecular, epidemiological, clinical and prognostic features of the precancerous biliary lesions, separated according to their origin in the bile ducts, the ampulla and the gall bladder.

The clinicopathological spectrum and management of intraductal papillary mucinous neoplasm of the bile duct (IPMN-B)

BACKGROUND

Intraductal papillary mucinous neoplasm of the bile duct (IPMN-B) is a rare but increasingly diagnosed clinical entity. Typical cholangioscopic findings usually include intraductal protruding papillary tumors that secrete mucus.

METHODS

Clinical, radiological and histopathological data of seven consecutive patients who were found to have IPMN-B were analyzed.

RESULTS

Six of the seven patients presented with obstructive jaundice/cholangitis as the presenting complaint. ERCP and other imaging were equivocal in five of these patients and peroral cholangioscopy (POCS, single-operator cholangioscopy system) was performed. This revealed mucin-producing intraductal tumors with numerous frond-like papillary projections; a macroscopic appearance consistent with IPMN-B. Preoperative biopsy revealed adenoma, with low-grade dysplasia in two patients and high-grade dysplasia in three. Three patients underwent Whipple resection; one underwent total pancreatectomy with left hepatectomy, one patient a pancreas preserving duodenectomy with common bile duct reimplantation and one patient an extended right hepatectomy. These patients were found to have IPMN-B with adenomatous changes with varying grades of dysplasia and even cholangiocarcinoma on final histopathology. One patient first underwent endoscopic papillectomy and on follow-up was found to have cholangiocarcinoma with metastases to the liver.

CONCLUSION

POCS can be a key diagnostic investigation in the evaluation of patients with papillary tumors of the bile duct. IPMN-B has a heterogenous pathology and varying grades of dysplasia and even carcinoma may exist in the same patient. Surgical management should be radical and based on tumor extent.

RNF43 is a tumour suppressor gene mutated in mucinous tumours of the ovary

Mucinous carcinomas represent a distinct morphological subtype which can arise from several organ sites, including the ovary, and their genetic characteristics are largely under-described. Exome sequencing of 12 primary mucinous ovarian tumours identified RNF43 as the most frequently somatically mutated novel gene, secondary to KRAS and mutated at a frequency equal to that of TP53 and BRAF. Further screening of RNF43 in a larger cohort of ovarian tumours identified additional mutations, with a total frequency of 2/22 (9%) in mucinous ovarian borderline tumours and 6/29 (21%) in mucinous ovarian carcinomas. Seven mutations were predicted to truncate the protein and one missense mutation was predicted to be deleterious by in silico analysis. Six tumours had allelic imbalance at the RNF43 locus, with loss of the wild-type allele. The mutation spectrum strongly suggests that RNF43 is an important tumour suppressor gene in mucinous ovarian tumours, similar to its reported role in mucinous pancreatic precancerous cysts.

A comparison between intraductal papillary neoplasms of the biliary tract (BT-IPMNs) and intraductal papillary mucinous neoplasms of the pancreas (P-IPMNs) reveals distinct clinical manifestations and outcomes

BACKGROUND

Intraductal papillary mucinous neoplasm of the biliary tract (BT-IPMN) has been increasingly recognized as a biliary counterpart of intraductal papillary mucinous neoplasm of the pancreas (P-IPMN). However, there is limited information regarding whether BT-IPMNs and P-IPMNs behave in a similar fashion.

METHODS

We retrospectively compared clinicopathological variables between 9 patients with BT-IPMN and 44 patients with P-IPMN.

RESULTS

There was no significant difference in age between patients with BT-IPMN and those with P-IPMN. The male/female ratio was significantly higher in patients with P-IPMN than in those with BT-IPMN (P = 0.012). Clinical presentation with jaundice was more common in patients with BT-IPMN (67%) than in those with P-IPMN (4.5%, P = 0.002). In addition, serum levels of CEA and CA19-9 were higher in patients with BT-IPMN than in those with P-IPMN (P = 0.019 and P = 0.002, respectively). The pathological diagnosis of malignancy was significantly more common in patients with BT-IPMN (89%) than in those with P-IPMN (23%, P = 0.002). The association with invasive carcinoma was significantly more frequent in patients with BT-IPMN (44.4%) than in those with P-IPMN (6.8%, P = 0.008). Furthermore, survival time after surgical resection was significantly shorter in patients with BT-IPMN than in those with P-IPMN (P = 0.002).

CONCLUSION

These findings reveal differences in clinicopathological features and prognosis between BT-IPMN and P-IPMN, thereby suggesting distinct biological pathways underlying the pathogenesis of these neoplasms.

Intrahepatic and extrahepatic intraductal papillary neoplasms of bile duct

There has been an increase in the number of reported cases of biliary neoplasm of the hepatobiliary system characterized by markedly dilated and multifocal papillary epithelial lesions of the bile ducts or cystic biliary lesions with or without mucin secretion, and mucinous lesions or tumors, possibly due to recent advances in radiological diagnosis. This lesion of the bile duct is believed to show a better clinical course than non-papillary biliary neoplasm. Therefore, the early recognition and treatment is important. We report two cases of intrahepatic and extrahepatic intraductal papillary neoplasm of the bile duct that were completely resected.

Intraductal tubular neoplasms of the bile ducts

Although most tumors of the bile ducts are predominantly invasive, some have an exophytic pattern within the bile ducts; these intraductal papillary neoplasms usually have well-formed papillae at the microscopic level. In this study, however, we describe a novel type of intraductal neoplasm of the bile ducts with a predominantly tubular growth pattern and other distinctive features. Ten cases of biliary intraductal neoplasms with a predominantly tubular architecture were identified in the files of the Pathology Department at Memorial Sloan-Kettering Cancer Center from 1983 to 2006. For each of these cases we studied the clinical presentation, histologic and immunohistochemical features (9 cases only), and the clinical follow-up of the patients. Three male and 7 female patients (38 to 78 y) presented with obstructive jaundice or abdominal pain. Eight of the patients underwent a partial hepatectomy; 2 underwent a laparoscopic bile duct excision, followed by a pancreatoduodenectomy in one of them. The tumors range in size from 0.6 to 8.0 cm. The intraductal portions of the tumors (8 intrahepatic, 1 extrahepatic hilar, 1 common bile duct) were densely cellular and composed of back-to-back tubular glands and solid sheets with minimal papillary architecture. The cells were cuboidal to columnar with mild to moderate cytologic atypia. Foci of necrosis were present in the intraductal component in 6 cases. An extraductal invasive carcinoma component was present in 7 cases, composing <25% of the tumor in 4 cases, and >75% in 1 case. It was observed by immunohistochemical analysis that the tumor cells expressed CK19, CA19-9, MUC1, and MUC6 in most cases and that SMAD4 expression was retained. MUC2, MUC5AC, HepPar1, synaptophysin, chromogranin, p53, and CA125 were negative in all cases and most were negative for CEA-M and B72.3. Four patients were free of tumor recurrence after 7 to 85 months (average, 27 mo). Four patients with an invasive carcinoma component suffered metastases, 1 after local intraductal recurrence. However, the occurrence of metastasis in 3 of these patients was quite late (average, 52 mo). Intraductal tubular neoplasm of the bile ducts is a biliary intraductal neoplasm with a distinctive histologic pattern resembling the recently described intraductal tubulopapillary neoplasm of the pancreas. Immunohistochemical features are similar to those of other pancreatobiliary-type carcinomas. However, this tumor may be hard to recognize as intraductal because of its complex architecture. When the tumor is entirely intraductal, the outcome appears to be favorable, but metastases can occur when invasive carcinoma is present, even after many years.

Clinicopathological features of the intraductal papillary neoplasms of the intrahepatic bile duct

Backgrounds/Aims

This study is intended to investigate the clinicopathological features of the intraductal papillary neoplasms of the intrahepatic bile duct (IPNB), especially focused on malignant changes.

Methods

From the institutional database of liver resection cases (Asan Medical Center, University of Ulsan College of Medicine), 18 patients who met the definition of IPNB were selected. They had undergone liver resection between February 2002 and October 2006; thus, the follow-up period was more than 5 years.

Results

Of the 18 patients, 11 patients were male. Their mean age was 61.3±6.7 years. There were no differences between the non-malignant and malignant lesions, in the comparison of the CEA levels (5.6±2.7 vs.12.6±31.1 ng/ml, p=0.439) and the CA19-9 levels (29.2±34.7 vs.31.9±30.2 ng/ml, p=0.871). The common radiologic findings were: intraductal growing mass in 10; bile duct dilatation in 6; and saccular duct dilatation in 2. Left and right hepatectomies were performed in 15 and 3, respectively. Five patients showed benign lesions of IPNB, and 13 patients revealed malignant lesions of intraductal papillary adnocarcinoma or cholangiocarcinoma. All 4 patients with benign lesions survived for a mean period of 53 months without recurrence. In 13 patients with the malignant lesions, 1-year, 3-year, and 5-year survival rates were 100%, 84.6%, and 59.2%, respectively.

Conclusions

We concluded that intrahepatic IPNB is a rare type of biliary neoplasm which includes a histological spectrum, ranging from benign disease to invasive malignancy. The long-term survival was anticipated after complete curative resection.

Intraductal papillary mucinous neoplasm of the pancreas: an update

Intraductal papillary mucinous neoplasm (IPMN) is a cystic tumor of the pancreas. The etiology is unknown, but increasing evidence suggests the involvement of several tumorigenesis pathways, including an association with hereditary syndromes. IPMN occurs more commonly in men, with the mean age at diagnosis between 64 and 67 years old. At the time of diagnosis, it may be benign, with or without dysplasia, or frankly malignant with an invasive carcinoma. Tumors arising from the main pancreatic duct are termed main-duct IPMNs, those involving the branch ducts, branch-duct IPMNs. In general, small branch-duct IPMNs are benign, particularly in asymptomatic patients, and can be safely followed. In contrast, main-duct tumors should be surgically resected and examined carefully for an invasive component. In the absence of invasion, patient's survival is excellent, from 94 to 100%. For patients with an IPMN-associated invasive carcinoma, the prognosis overall is better than those with a de novo pancreatic ductal adenocarcinoma, with a 5-year survival of 40% to 60% in some series. However, no survival advantage can be demonstrated if the invasive component in an IPMN patient is that of the conventional tubular type (versus mucinous carcinoma). Several histomorphologic variants are recognized, although the clinical significance of this "subtyping" is not well defined.

Gallbladder Papillary Neoplasia Associated With Intrahepatic Carcinoma and Pancreaticobiliary Malformation

Papillary carcinoma is a rare tumor of the gallbladder. Papillary mucinous lesions of the intra- and extra-hepatic biliary tract (BT- IPMN) have been recognized. However the gallbladder is not included, except for the diffuse papillomatosis, where the sequence biliary papillomatosis to papillary carcinoma is proposed. We report a simultaneous case of gallbladder papillary neoplasia and intrahepatic duct carcinoma in situ associated with pancreaticobiliary maljunction (PBM). We proposed that double location, in our case, is more likely explained by a diffuse biliopancreatic tree disease leading to synchronous tumors arising in amenable duct. It was verified absence of continuity between gallbladder and intrahepatic bile duct site of involvement, absence of lymph node metastasis or venous involvement. This case report supports the concept of a proliferative and neoplastic process involving simultaneously the biliary tree and gallbladder associated with PBM.

Intracholecystic papillary-tubular neoplasms (ICPN) of the gallbladder (neoplastic polyps, adenomas, and papillary neoplasms that are ≥1.0 cm): clinicopathologic and immunohistochemical analysis of 123 cases

The literature on the clinicopathologic characteristics of tumoral intraepithelial neoplasms (neoplastic polyps) of the gallbladder (GB) is fairly limited, due in part to the variability in definition and terminology. Most reported adenomas (pyloric gland type and others) were microscopic and thus regarded as clinically inconsequential, whereas papillary in situ carcinomas have been largely considered a type of invasive adenocarcinoma under the heading of "papillary adenocarcinomas." In this study, 123 GB cases that have a well-defined exophytic preinvasive neoplasm measuring ≥1 cm were analyzed. The patients were predominantly female (F/M=2:1) with a mean age of 61 y and a median tumor size of 2.2 cm. Half of the patients presented with pain, and in the other half the neoplasm was detected incidentally. Other neoplasms, most being gastrointestinal tract malignancies, were present in 22% of cases. Gallstones were identified in only 20% of cases. Radiologically, almost half were diagnosed as "cancer," roughly half with polypoid tumor, and in 10% the lesion was missed. Pathologic findings: (1) The predominant configuration was papillary in 43%, tubulopapillary in 31%, tubular in 26%. (2) Each case was assigned a final lineage type on the basis of the predominant pattern (>75% of the lesion) on morphology, and supported with specific immunohistochemical cell lineage markers. The predominant cell lineage could be identified as biliary in 50% (66% of which were MUC1), gastric foveolar in 16% (all were MUC5AC), gastric pyloric in 20% (92% MUC6), intestinal in 8% (100% CK20; 75% CDX2; 50%, MUC2), and oncocytic in 6% (17% HepPar and 17% MUC6); however, 90% of cases had some amount of secondary or unclassifiable pattern and hybrid immunophenotypes. (3) Of the cases that would have qualified as "pyloric gland adenoma," 21/24 (88%) had at least focal high-grade dysplasia and 18% had associated invasive carcinoma. Conversely, 8 of 47 "papillary adenocarcinoma"-type cases displayed some foci of low-grade dysplasia, and 15/47 (32%) had no identifiable invasion. (4) Overall, 55% of the cases had an associated invasive carcinoma (pancreatobiliary type, 58; others, 10). Factors associated significantly with invasion were the extent of high-grade dysplasia, cell type (biliary or foveolar), and papilla formation. Among systematically analyzed invasive carcinomas, tumoral intraepithelial neoplasia was detected in 6.4% (39/606). (5) The 3-year actuarial survival was 90% for cases without invasion and 60% for those associated with invasion. In contrast, those associated with invasion had a far better clinical outcome compared with pancreatobiliary-type GB carcinomas (3-yr survival, 27%), and this survival advantage persisted even with stage-matched comparison. Death occurred in long-term follow-up even in a few noninvasive cases (4/55; median 73.5 mo) emphasizing the importance of long-term follow-up. In conclusion, tumoral preinvasive neoplasms (≥1 cm) in the GB are analogous to their pancreatic and biliary counterparts (biliary intraductal papillary neoplasms, pancreatic intraductal papillary mucinous neoplasms, and intraductal tubulopapillary neoplasms). They show variable cellular lineages, a spectrum of dysplasia, and a mixture of papillary or tubular growth patterns, often with significant overlap, warranting their classification under 1 unified parallel category, intracholecystic papillary-tubular neoplasm. Intracholecystic papillary-tubular neoplasms are relatively indolent neoplasia with significantly better prognosis compared with pancreatobiliary-type GB carcinomas. In contrast, even seemingly innocuous examples such as those referred to as "pyloric gland adenomas" can progress to carcinoma and be associated with invasion and fatal outcome.

Diagnostic challenge: intraductal neoplasms of the pancreatobiliary system

To help pathologists avoid misdiagnosis of intraductal neoplasms arising from the pancreatobiliary system, we report two cases that illustrate diagnostic pitfalls. The first is of a 66-year-old man who complained of appetite loss. An early examination led to a diagnosis of intraductal papillary mucinous neoplasm. Macroscopically, a multilocular cyst without visible mucin was identified. Histologically, the compartments consisted of complex fusion of tubular glands surrounded by dilated pancreatic duct. The neoplasm resembled an acinar cell cystadenocarcinoma. However, the neoplastic cells were negative for trypsin. Thus, the final histopathologic diagnosis was an unusual cystic variant of intraductal tubulopapillary neoplasm (ITPN) of the pancreas. The second case is of a 71-year-old man who complained of right upper quadrant pain. Although bile duct stone was suspected, a polypoid nodule was extracted. Histologically, the nodule was composed of tubular glands, with some complex fusion and focal dysplasia, consistent with carcinoma. In addition, lack of MUC-5AC expression led to an initial impression of ITPN of the bile duct. However, the neoplasm showed dysplastic cells based on the columnar cells resembling pyloric glands, indicating the sequential progression. Thus, the final histopathological diagnosis was intraductal papillary neoplasm of the bile duct with high-grade intraepithelial neoplasia. Because phenotypic variants of intraductal neoplasms of the pancreatobiliary system exist, ITPN and ITPN-mimicking tumor must be carefully differentiated from other intraductal neoplasms.

GNAS codon 201 mutations are uncommon in intraductal papillary neoplasms of the bile duct

BACKGROUND

Activating point mutations of GNAS at codon 201 have been detected in approximately two thirds of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas. Intraductal papillary neoplasms of the bile ducts (IPNBs) morphologically resemble pancreatic IPMNs. This study sought to assess the mutational status of GNAS at codon 201 in IPNBs.

METHODS

Thirty-four patients were included. DNA from microdissected IPNBs was subjected to a polymerase chain reaction and ligation method for the detection of GNAS mutations at codon 201 and of KRAS mutations at codon 12. Mutational status was compared with clinical and pathologic data.

RESULTS

The IPNBs had a median diameter of 3.5 cm and were located intrahepatically (n= 6), extrahepatically (n= 13), both intra- and extrahepatically (n= 4) or in the gallbladder (intracystic papillary neoplasms, n= 11). Most exhibited pancreatobiliary differentiation (n= 20), high-grade dysplasia (n= 26) and an associated adenocarcinoma (n= 20). Analysis of GNAS codon 201 identified only one mutant sample in a multifocal intestinal subtype intrahepatic IPNB with high-grade dysplasia. Six lesions harboured a KRAS codon 12 mutation.

CONCLUSIONS

GNAS codon 201 mutations are uncommon in IPNBs, by contrast with pancreatic IPMNs. More comprehensive molecular profiling is needed to uncover the pathways involved in IPNB development.

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

Intraductal papillary neoplasm of the bile duct (IPNB) is a variant of bile duct carcinoma characterized by intraductal growth and better outcome compared with the more common nodular-sclerosing type. IPNB is a recognized precursor of invasive carcinoma, but its pathogenesis and natural history are ill-defined. This study examines the clinicopathologic features and outcomes of IPNB. A consecutive cohort of patients with bile duct cancer (hilar, intrahepatic, or distal) was reviewed, and those with papillary histologic features identified. Histopathologic findings and immunohistochemical staining for tumor markers and for cytokeratin and mucin proteins were used to classify IPNB into subtypes. Survival data were analyzed and correlated with clinical and pathologic parameters. Thirty-nine IPNBs were identified in hilar (23/144), intrahepatic (4/86), and distal (12/113) bile duct specimens between 1991 and 2010. Histopathologic examination revealed 27 pancreatobiliary, four gastric, two intestinal, and six oncocytic subtypes; results of cytokeratin and mucin staining were similar to those of intraductal papillary mucinous neoplasm (IPMN) of the pancreas. Invasive carcinoma was seen in 29/39 (74%) IPNBs. Overall median survival was 62 months and was not different between IPNB locations or subtypes. Factors associated with a worse median survival included presence and depth of tumor invasion, margin-positive resection, and expression of MUC1 and CEA.

CONCLUSION

IPNBs are an uncommon variant of bile duct cancer, representing approximately 10% of all resectable cases. They occur throughout the biliary tract, share some histologic and clinical features with IPMNs of the pancreas, and may represent a carcinogenesis pathway different from that of conventional bile duct carcinomas arising from flat dysplasia. Given their significant risk of harboring invasive carcinoma, they should be treated with complete resection.

Long-term clinical outcome of the surgically resected intraductal papillary neoplasm of the bile duct

BACKGROUND & AIMS

Intraductal papillary neoplasm of the bile duct (IPNB) is a biliary neoplasm with predominant intraductal papillary growth and various degrees of malignant transformation. Although IPNB has been recently added to the WHO classification, the classification system needs refinements.

METHODS

We retrospectively reviewed 93 non-invasive and invasive IPNB cases, surgically resected from 1996 to 2006. To further characterize their biologic behavior, we modified the WHO classification into a 4-tier category system in which non-invasive IPNB cases with complex fused or cribriform papillae were separately designated. Epithelial types such as intestinal, gastric, pancreatobiliary, and oncocytic type were determined by morphology and mucin core protein immunohistochemistry. Resection margins were classified based on their microscopic appearances. The prognostic values of mucinous histology and MUC1 protein expression were also determined.

RESULTS

IPNB with complex fused or cribriform papillae showed a worse prognosis than IPNB with simple papillae and one such case showed a metachronous metastasis. In addition, a positive surgical margin including dysplasia was associated with worse outcomes. Among the invasive IPNB cases, MUC1-positive tumors were more aggressive than MUC1-negative tumors.

CONCLUSIONS

We propose that non-invasive IPNB with complex fused or cribriform papillae might be better classified as mucosa-confined cholangiocarcinoma rather than IPNB with high grade dysplasia. In addition, aggressive further resection is recommended when a positive surgical margin including dysplasia is reported during intraoperative histopathological evaluation.

Intraductal neoplasm of the intrahepatic bile duct: Clinicopathological study of 24 cases

AIM: To investigate the clinicopathological features of intraductal neoplasm of the intrahepatic bile duct (INihB).

METHODS: Clinicopathological features of 24 cases of INihB, which were previously diagnosed as biliary papillomatosis or intraductal growth of intrahepatic biliary neoplasm, were reviewed. Mucin immunohistochemistry was performed for mucin (MUC)1, MUC2, MUC5AC and MUC6. Ki-67, P53 and β-catenin immunoreactivity were also examined. We categorized each tumor as adenoma (low grade), borderline (intermediate grade), and malignant (carcinoma in situ, high grade including tumors with microinvasion).

RESULTS: Among 24 cases of INihB, we identified 24 tumors. Twenty of 24 tumors (83%) were composed of a papillary structure; the same feature observed in intraductal papillary neoplasm of the bile duct (IPNB). In contrast, the remaining four tumors (17%) showed both tubular and papillary structures. In three of the four tumors (75%), macroscopic mucin secretion was limited but microscopic intracellular mucin was evident. Histologically, 16 tumors (67%) were malignant, three (12%) were borderline, and five (21%) were adenoma. Microinvasion was found in four cases (17%). Immunohistochemical analysis revealed that MUC1 was not expressed in the borderline/adenoma group but was expressed only in malignant lesions (P = 0.0095). Ki-67 labeling index (LI) was significantly higher in the malignant group than in the borderline/adenoma group (22.2 ± 15.5 vs 7.5 ± 6.3, P < 0.01). In the 16 malignant cases, expression of MUC5AC showed borderline significant association with high Ki-67 LI (P = 0.0622). Nuclear expression of β-catenin was observed in two (8%) of the 24 tumors, and these two tumors also showed MUC1 expression. P53 was negative in all tumors.

CONCLUSION: Some cases of INihB have a tubular structure, and are subcategorized as IPNB with tubular structure. MUC1 expression in INihB correlates positively with degree of malignancy.

Adenocarcinoma with pyloric gland phenotype of the extrahepatic bile ducts: a previously unrecognized and distinctive morphologic variant of extrahepatic bile duct carcinoma

Carcinomas of the extrahepatic bile ducts are uncommon and morphologically heterogeneous. We report 3 unique examples of adenocarcinomas that show predominantly pyloric gland differentiation (80%-100%) and compare their immunohistochemical profile with that of pyloric gland adenomas of the gallbladder, foveolar, and intestinal-type adenocarcinomas of the extrahepatic bile duct. The 3 patients with pyloric gland adenocarcinomas were younger than those with conventional adenocarcinomas. The 3 tumors were very well differentiated but showed extensive perineural invasion. They consisted of a variable proportion of small, medium-sized, and cystically dilated glands separated by abundant desmoplastic stroma. The glands were lined by columnar cells with abundant mucin-containing cytoplasm and small hyperchromatic basally placed nuclei with inconspicuous nucleoli. A characteristic feature of these pyloric gland adenocarcinomas was that the glands had a stellar pattern that was not seen in foveolar-, intestinal-, or biliary-type adenocarcinomas. Two pyloric gland adenocarcinomas coexpressed MUC6 and MUC5AC. The diffuse pattern of reactivity of MUC5AC and MUC6 was similar to that of 10 pyloric gland adenomas of the gallbladder and 2 foveolar adenocarcinomas of the extrahepatic bile duct. In contrast, 5 intestinal adenocarcinomas of the extrahepatic bile duct labeled with the intestinal marker CDX2 and 3 with the colonic MUC2 but were negative for MUC6 and MUC5AC. We believe that these pyloric gland adenocarcinomas represent a previously unrecognized distinct clinicopathologic entity. Despite their deceptively benign microscopic appearance, 1 patient died with local recurrence and liver metastasis, another patient is living with tumor, and the third patient is asymptomatic but only 5 months after surgery.

Intraductal oncocytic papillary neoplasm of the extrahepatic bile duct: report of a case

We report a rare case of an intraductal oncocytic papillary neoplasm (IOPN) of the extrahepatic bile duct. A 66-year-old man was admitted to our hospital for investigation of right-sided back pain. Ultrasonography, computed tomography and magnetic resonance imaging showed a papillary lesion, 3 cm in diameter, in the middle bile duct, invaginating into the cystic duct. We made a provisional diagnosis of middle bile duct cancer and performed substomach-preserving pancreatoduodenectomy. Macroscopically, the middle bile duct contained a two-humped papillary tumor, one tip of which invaginated into the cystic duct. Microscopically, the tumor consisted of cuboidal cells with abundant eosinophilic cytoplasm resembling that of oncocytes and a fine fibrovascular core. The tumor cells were stained strongly with antimitochondria antibody. Based on these findings, the tumor was diagnosed histologically as IOPN of the extrahepatic bile duct. The patient died of prostate cancer 51 months after surgery, but without evidence of recurrence of the IOPN.

Immunohistochemical characteristics and malignant progression of hepatic cystic neoplasms in comparison with pancreatic counterparts

The recent World Health Organization classification for tumors of the digestive system defined grossly and histologically hepatic mucinous cystic neoplasms and intraductal papillary neoplasms of the bile duct separately. In this study, the immunohistochemical features of intraductal papillary neoplasm of the bile duct (19 cases) and hepatic mucinous cystic neoplasm (5 cases) were characterized and compared with those of similar pancreatic lesions, intraductal papillary mucinous neoplasm of the pancreas (12 cases), and pancreatic mucinous cystic neoplasm (6 cases) and with those of other biliary cystic lesions, peribiliary cysts (10 cases). Intraductal papillary neoplasm of the bile duct and intraductal papillary mucinous neoplasm of the pancreas frequently expressed cytokeratin 7; mucin core proteins 1, 2, 5AC, and 6; trypsin; and amylase. Hepatic and pancreatic mucinous cystic neoplasms frequently expressed cytokeratin 7, mucin core proteins 1 and 5AC, estrogen receptor, progesterone receptor, trypsin, and amylase. Estrogen and progesterone receptors were expressed in the subepithelial stromal cells. The groups with intraductal papillary neoplasm of the bile duct and intraductal papillary mucinous neoplasm of the pancreas were different from the groups with hepatic and pancreatic mucinous cystic neoplasm with respect to several phenotypes reflecting gastric and intestinal metaplasia and also the lack of expression of estrogen and progesterone receptors. The Ki-67 and p53 labeling indexes increased significantly with the malignant progression of intraductal papillary neoplasm of the bile duct and intraductal papillary mucinous neoplasm of the pancreas. The p16 labeling index decreased and EZH2 labeling index increased significantly with the malignant progression of intraductal papillary neoplasm of the bile duct and intraductal papillary mucinous neoplasm of the pancreas. In conclusion, intraductal papillary neoplasm of the bile duct and hepatic mucinous cystic neoplasm might be regarded as biliary counterparts of intraductal papillary mucinous neoplasm of the pancreas and pancreatic mucinous cystic neoplasm, respectively, and the mucinous cystic neoplasm and intraductal papillary neoplasm groups differed from each other. Labeling indexes of Ki-67, p53, p16, and EZH2 were comparable in intraductal papillary neoplasm of the bile duct and intraductal papillary mucinous neoplasm of the pancreas along with their malignant progression, suggesting a common carcinogenic process of the tumors.

Distinctive expression of CD133 between intraductal papillary neoplasms of the bile duct and bile duct adenocarcinomas

AIM

  Intraductal papillary neoplasm of the bile duct (IPNB), a novel entity of biliary disease, is recently advocated as the counterpart of pancreatic intraductal papillary mucinous neoplasm (IPMN) because both are in common with a large amount of mucin production and papillary growth. Based on our recent finding that expression of CD133, a cancer stem cell marker, is lacking in pancreatic IPMN, we herein focused on CD133 expression of IPNB in comparison with intrahepatic cholangiocellular carcinoma (IHCCC) or hilar bile duct cancer (HBDC).

METHODS

  Expression of CD133 protein was immunohistochemically determined in patients with IPNB (n = 7), IHCCC (n = 16) or HBDC (n = 8). In addition, morphological and immunohistochemical mucin expression patterns were characterized in IPNB, and clinicopathological features including prognosis were compared between IPNB and other biliary tumors.

RESULTS

  The IPNB group included significantly more females than the other two groups, and had a longer survival time. While no CD133 expression was observed in IPNB tumor, 16.4% of cancer cells in IHCCC and 17.2% of cells in HBDC expressed CD133. Among seven patients with IPNB, six (86%) were morphologically the pancreatobiliary type and four of six showed mucin expression pattern of the typical pancreatobiliary type (MUC1+/MUC2-/MUC5AC+).

CONCLUSION

  Loss of CD133 expression supports the hypothesis that IPNB is a counterpart of pancreatic IPMN with a differing carcinogenesis from conventional bile duct adenocarcinomas.

Follicular cholangitis and pancreatitis - clinicopathological features and differential diagnosis of an under-recognized entity

AIMS

Biliary and pancreatic ductal systems can be involved in several lymphoplasmacytic inflammatory conditions, including primary sclerosing cholangitis, immunoglobulin G (IgG) 4-related cholangitis and autoimmune pancreatitis. Here in we describe an unusual pancreatocholangitis whose features suggest a distinct disease entity.

METHODS AND RESULTS

The study group consists of five adult patients, three with predominantly hilar bile duct stricture and two with a bulky pancreatic head. Four patients were treated surgically for suspected malignancy and one patient underwent liver transplantation with a clinical diagnosis of primary sclerosing cholangitis. Histological examination revealed extensive lymphoplasmacytic inflammation centred on large biliary or pancreatic ducts. Many lymphoid follicles with germinal centres were noted around the affected ducts. Whipple specimens from two patients with a pancreatic head mass showed similar follicular inflammation histologically around bile ducts. In contrast to autoimmune pancreatitis, diffuse infiltration of IgG4(+) plasma cells, granulocytic epithelial lesions and obliterative phlebitis were not identified. The postoperative course was uneventful, without evidence of recurrence (follow-up period 17-65 months).

CONCLUSIONS

This study suggests that a disease entity which can be named follicular cholangitis and pancreatitis exists and may be under-recognized. The disease mainly affects the hilar bile ducts and pancreatic head in adults.

F-18 FDG uptake in borderline intraductal papillary neoplasms of the bile duct

Intraductal papillary neoplasm of the bile duct (IPN-B) has been recently proposed as the biliary counterpart of intraductal papillary mucinous neoplasm of the pancreas. Histologically, IPN-B can be classified into adenoma, borderline, carcinoma in situ, and invasive carcinoma. Two patients with suspected intraductal tumor underwent fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography. One patient showed an FDG-avid tumor in the right liver with SUV(max) of 9.4 in early images and 11.3 in delayed images. The patient underwent complete tumor resection. Adenoma with high-grade dysplasia was confirmed by pathology. The other patient showed an FDG-avid polypoid lesion at the distal common bile duct with SUV(max) of 5.4. The lesion was endoscopically resected. Histopathologic findings showed adenoma with low-grade dysplasia. These two cases highlight that IPN-B should be included in the differential diagnosis of abnormal biliary intraductal FDG accumulation along with carcinoma, and inflammatory and infectious processes.

Two distinct pathways of carcinogenesis in primary sclerosing cholangitis

AIMS

To identify clinicopathological characteristics of cholangiocarcinoma and premalignant lesions arising in patients with primary sclerosing cholangitis (PSC).

METHODS AND RESULTS

This study consisted of 25 patients with PSC and bile duct neoplasia [16 with cholangiocarcinoma and nine with biliary intra-epithelial neoplasia (BilIN) equivalent to biliary dysplasia]. Tumour cell morphology, growth patterns, history of inflammatory bowel disease and postoperative survival were recorded. Immunohistochemistry for CK7, CK20, MUC1, MUC2, MUC5AC, MUC6 and CDX2 was performed to characterize cell phenotypes. Cholangiocarcinoma and BilIN were classified into intestinal (n = 14) and non-intestinal classical (n = 11) types. Intestinal-type lesions showed histological features resembling intestinal dysplasia or adenocarcinoma. Intestinal-type cholangiocarcinoma commonly showed intraductal papillary proliferation and mucinous nodule formation. Intestinal-type lesions often had an intestinal immunophenotype that was not detected in classical-type lesions: CK20, 50% versus 0% (P = 0.007); MUC2, 86% versus 0% (P < 0.001); CDX2, 54% versus 0% (P = 0.003). Less commonly, intestinal-type cholangiocarcinoma showed perineural invasion (P = 0.003). Patients with intestinal-type cholangiocarcinoma had a more favourable cancer-specific prognosis than those with classical-type cholangiocarcinoma (P = 0.043).

CONCLUSIONS

Bile ducts in PSC show two distinct dysplasia-carcinoma sequences as evidenced by differences in cell morphology, growth patterns, immunophenotypes and grade of malignancy.

Intraductal papillary neoplasm arising from peribiliary glands connecting with the inferior branch of the bile duct of the anterior segment of the liver

Intraductal papillary neoplasms of the bile duct are generally thought to arise from neoplastic papillary proliferation of epithelial cells lining the bile duct. We herein report a case with findings that strongly suggested that the biliary cystic tumor might have derived from a peribiliary gland. A 69-year-old female was found to have a cystic lesion with intracystic protrusions at the anterior segment of the right hepatic lobe and underwent hepatic anterior segment resection. Fluoroscopy of the resected specimen injected with contrast medium into the cyst revealed a connection between the cystic lesion and the bile ducts. The cyst was multilocular in appearance. On microscopic examination, the cyst was located within the portal tract of the inferior branch of the anterior segment and connected with the inferior branch of the bile duct. The wall of the hepatic cyst lacked an ovarian-like stroma. The tumor was composed of papillary and glandular components, and the tumor cells were similar to gastric foveolar and pyloric gland epithelia and regarded as adenoma. These tumor cells were positive for MUC 5AC, MUC6, and HIK1083. The tumor was finally diagnosed as an intraductal papillary neoplasm of the bile duct (adenoma, gastric type) arising from a peribiliary gland.

[Precursor lesions of pancreatobiliary cancer]

Precursor lesions of pancreatobiliary cancer can be divided into cystic and flat lesions. Mucinous cystic neoplasm and intraductal papillary mucinous neoplasm (IPMN) comprise the cystic precursors in the pancreas, while intraductal papillary neoplasm (IPN) represents their counterpart in the bile duct system. There is an adenoma-carcinoma sequence in the cystic precursors arising from four different types of epithelia: pancreatobiliary, oncocytic, intestinal and gastric. These subtypes of IPMN/IPN are morphologically and immunohistochemically well characterised and show clinical and prognostic relevance: the gastric subtype is associated with the best prognosis, followed by the oncocytic and intestinal subtypes, while the pancreatobiliary subtype is characterized by adverse clinical behaviour. Pancreatic intraepithelial neoplasia (PanIN) and biliary intraepithelial neoplasia (BilIN) represent the flat precursors. PanIN are morphologically and biologically well defined. PanIN with lobulocentric atrophy has recently been described as a putative precursor of pancreatic cancer. Despite well defined morphological features in BilIN, the molecular alterations seen during early tumor progression in the biliary tract are poorly understood.

Pseudomyxoma peritonei (mucinous carcinoma peritonei) preceded by intraductal papillary neoplasm of the bile duct

Pseudomyxoma peritonei (mucinous carcinoma peritonei) is a rare clinical disease. Although most cases derive from appendiceal mucinous tumors, a few are associated with pancreatic intraductal papillary mucinous neoplasms. Intraductal papillary neoplasms of the bile duct share many similarities with pancreatic intraductal papillary mucinous neoplasms and are thought to be their biliary counterparts. We report a case of low-grade intraductal papillary neoplasm of the bile duct who developed pseudomyxoma peritonei 6 years after surgical treatment of the primary biliary tumor. To the best of our knowledge, this is the first case of pseudomyxoma peritonei associated with intraductal papillary neoplasm of the bile duct. The tumor recurrence in our case may be due to tumor spillage at the time of the first surgery, since there is no recurrent biliary tumor in the preserved liver lobe. Prevention of spillage of epithelial cell-containing mucin during surgical operations is important in treating intraductal papillary neoplasms of the bile duct.

The clinicopathological features of intraductal papillary neoplasms of the bile duct in a Chinese population

BACKGROUND

Intraductal papillary neoplasms of the bile duct have been applied to certain types of papillary tumours occurring in the biliary tract. Although many cases have been sporadically reported, there remain controversies.

AIMS

To analyze the clinicopathologic characteristics and long-term survival of intraductal papillary neoplasms of the bile duct.

METHODS

The clinicopathologic data of 52 patients who underwent surgery for intraductal papillary neoplasms of the bile duct were retrospectively evaluated.

RESULTS

In our series, tumours located in intrahepatic and hilar bile duct, rather than in extrahepatic bile duct, were more commonly diagnosed as adenomas or borderline tumours (12/19 and 7/13 vs 6/20; P=0.046). And the gastric type was more commonly associated with adenomas or borderline tumour (85.7%), whilst the pancreaticobiliary type mainly comprised of noninvasive carcinoma or invasive carcinoma (93.8%). However, only the types of treatment (median survival: curative resection: 72 months and palliative groups: 12 months; P<0.001) and histologic grades (adenoma or borderline malignancy vs noninvasive carcinoma: P=0.018) were significantly associated with survival.

CONCLUSION

Intraductal papillary neoplasms of the bile duct are rare type of biliary neoplasms, long-term survival may be achieved with complete resection. However, further studies are needed to clarify the relationship between these variables like location, cellular types and histologic grades.

Simultaneous intraductal papillary neoplasms of the bile duct and pancreas treated with chemoradiotherapy

Some authors have suggested that intraductal papillary mucinous neoplasms of the bile duct (IPMN-B) could be the the biliary counterpart of IPMN of the pancreas (IPMN-P) since they share several clinical-pathological features. These include prominent intraductal papillary proliferation pattern, a gastrointestinal phenotype, frequent mucin hyper-secretion and progression to mucinous carcinoma. To date there are just four reported cases of patients with synchronous IPMN-B and IPMN-P all of which were treated surgically. We hereby report the case of a 76-year-old woman who was incidentally diagnosed with both an asymptomatic 3 cm bulky fluid lesion obstructing the bile duct lumen, diagnosed as a malignant IPMN-B, and synchronous multiple pancreatic cystic lesions (10-13 mm) communicating with an irregular Wirsung, diagnosed as branch duct IPMN-P. Since surgery was ruled-out because of the patient’s age and preferences, she underwent a conservative management regimen comprising both chemotherapy and radiotherapy. This was effective in decreasing the mass size and in resolving subsequent jaundice. This is also the first reported case of IPMN-B successfully treated with chemoradiotherapy. Clinicians should consider medical treatment as an option in this clinical scenario, in patients who may be unfit for surgery.

Kras(G12D) and p53 mutation cause primary intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (IHCC) is a primary cancer of the liver with an increasing incidence and poor prognosis. Preclinical studies of the etiology and treatment of this disease are hampered by the relatively small number of available IHCC cell lines or genetically faithful animal models. Here we report the development of a genetically engineered mouse model of IHCC that incorporates two of the most common mutations in human IHCC, activating mutations of Kras (Kras(G12D)) and deletion of p53. Tissue-specific activation of Kras(G12D) alone resulted in the development of invasive IHCC with low penetrance and long latency. Latency was shortened by combining Kras(G12D) activation with heterozygous or homozygous deletion of p53 (mean survival of 56 weeks vs. 19 weeks, respectively), which also resulted in widespread local and distant metastasis. Serial analysis showed that the murine models closely recapitulated the multistage histopathologic progression of the human disease, including the development of stroma-rich tumors and the premalignant biliary lesions, intraductal papillary biliary neoplasms (IPBN), and Von Meyenburg complexes (VMC; also known as biliary hamartomas). These findings establish a new genetically and histopathologically faithful model of IHCC and lend experimental support to the hypothesis that IPBN and VMC are precursors to invasive cancers.

Pathological spectrum of intrahepatic cholangiocarcinoma arising in non-biliary chronic advanced liver diseases

Intrahepatic cholangiocarcinoma (ICC) is reported to develop in non-biliary chronic advanced liver diseases (CALD). Herein, we characterize the pathological features of ICC arising in CALD in comparison with those in non-CALD livers. Of 471 surgically resected cases of ICC in Kanazawa, Japan and Seoul, Korea, 53 were associated with CALD (group A), while the remaining 418 arose in otherwise normal livers (group B). When ICC were classified into bile duct type, bile ductular type, variants, and intraductal papillary neoplasm of the bile duct (IPNB), the whole spectrum of subtypes were found in group A; the majority of ICC belonged to the bile duct type in both groups. In group A, bile ductular type was rather frequent (22.6%) compared with group B (8.4%). IPNB was more frequent in group B (22.5%) than group A (3.8%), and in group B, frequent in Seoul cases (24.8%), but rare in Kanazawa cases (2.3%). Variants of ICC were rare in both groups. These results imply that cholangiocarcinogenesis itself is upregulated in group A in comparison with group B and that the bile ductular type is specifically related to group A. Some unique environmental factors in Seoul may be responsible for the frequent development of IPNB.

Clinicopathologic features of intraductal papillary neoplasm of the bile duct according to histologic subtype

OBJECTIVES

Despite an increase in the reports of intraductal papillary neoplasm of the bile duct (IPN-B), the clinical characteristics and long-term prognosis of this disease are not well known compared with those of intraductal papillary mucinous neoplasms of the pancreas. The objective of our study was to compare the clinical features, radiologic findings, and clinical outcomes of IPN-B according to histologic subtype.

METHODS

A retrospective analysis was performed on the medical records of 97 patients diagnosed with IPN-B by pathologic analysis of their surgical specimens between May 1995 and May 2010. We compared the clinical manifestations, radiological findings, pathologic grade, curative resection rate, recurrence, and overall survival according to four histologic subtypes: gastric (n=15), intestinal (n=46), pancreaticobiliary (n=33), and oncocytic (n=3), which were classified on the basis of hematoxylin and eosin staining and the immunohistochemical profile of mucin core proteins.

RESULTS

Mucin hypersecretion was significantly more frequent in patients with gastric and intestinal types than it was in those with oncocytic and pancreaticobiliary types (P=0.014). There were no significant differences between groups regarding the presence of bile duct stones or tumor location. The frequency of invasive carcinoma in the pancreaticobiliary type was significantly higher than those in the gastric and intestinal types (72.7 vs. 26.7 and 32.6%, P<0.001 and P<0.001). When comparing the survival curves according to histologic subtype, patients with pancreaticobiliary type demonstrated significantly worse survival compared to those with gastric and intestinal types (P=0.035).

CONCLUSIONS

Gastric and intestinal types of IPN-B have similar clinical characteristics compared with the pancreaticobiliary type, which has a worse prognosis.

Tutorial review for understanding of cholangiopathy

The biliary tree consists of intrahepatic and extrahepatic bile ducts and is lined by biliary epithelial cells (or cholangiocytes). There are also peribiliary glands around the intrahepatic large bile ducts and extrahepatic bile ducts. The biliary tree is a conduit of bile secreted by hepatocytes and biliary epithelial cells and also of the peribiliary glands and has several physiological roles. A number of diseases affect mainly the intrahepatic and extrahepatic biliary tree, and, in this special issue, these cholangiopathies are reviewed in detail with respect to genetics, pathogenesis, and pathology. In this paper, the anatomy and physiology of the biliary tree, basic injuries to biliary epithelial cells from stress and bile duct damage, and representative cholangiopathies are briefly reviewed.

Cyst-forming intraductal papillary neoplasm of the bile ducts: description of imaging and pathologic aspects

OBJECTIVE

Intraductal papillary neoplasm (IPN) of the bile duct is a newly described pathologic entity characterized by the presence of intraluminal tumors, which sometimes produce a large amount of mucin and form a cystic tumor. Cystic IPN of the bile duct is different from biliary cystadenoma or cystadenocarcinoma in that the former produces intraductal microscopic and macroscopic papillary tumors without ovarian-like stroma, whereas the latter produce a mucin-containing septate cystic tumor without communication with bile duct and with ovarian-like stroma in the cyst wall. The purpose of this study was to evaluate the potential relationships between cyst-forming IPNs of the bile duct and peribiliary glands and also intraductal papillary mucinous neoplasms of the pancreas.

MATERIALS AND METHODS

From a cohort of 87 patients with surgically resected and pathologically proved IPN of the bile duct, 12 patients with cystic IPN of the bile duct who underwent CT (n = 12), MRCP (n = 3), ultrasound (n = 3), and ERCP (n = 4) were included. Imaging findings were evaluated for the relationship of cystic tumors to the bile ducts; in particular, a diverticulum-like appearance was considered as suggestive of the peribiliary gland origin. Pathologic examination was conducted, and both gross and microscopic findings were recorded.

RESULTS

Radiologic examination revealed aneurysm-like dilatation of the involved bile ducts in five patients and intrahepatic biliary cystic tumor in two patients. Interestingly, the remaining five patients had diverticulum-like cystic tumor with or without communication; one patient had a cystic tumor laterally attached to the extrahepatic bile duct. Histopathologically, cystic tumors are lined by atypical biliary epithelium showing intracystic papillary proliferation, with an appearance similar to that of pancreatic intraductal papillary mucinous neoplasm.

CONCLUSION

This study suggests that cyst-forming IPN of the bile duct may be a biliary counterpart to pancreatic intraductal papillary mucinous neoplasm. In particular, at least some of the tumors seem to arise from peribiliary glands, and these cases might be a counterpart to branch-duct intraductal papillary mucinous neoplasm of the pancreas, given the histologic similarity between peribiliary glands and pancreatic branch ducts.