Clinical studies of mucin-producing cholangiocellular carcinoma: a study of 22 histopathology-proven cases

Recent Advances in Pathology of Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICCA) is a malignant epithelial neoplasm characterized by biliary differentiation within the liver. ICCA is molecularly heterogeneous and exhibits a broad spectrum of histopathological features. It is a highly aggressive carcinoma with high mortality and poor survival rates. ICCAs are classified into two main subtypes: the small-duct type and large-duct types. These two tumor types have different cell origins and clinicopathological features. ICCAs are characterized by numerous molecular alterations, including mutations in KRAS, TP53, IDH1/2, ARID1A, BAP1, BRAF, SAMD4, and EGFR, and FGFR2 fusion. Two main molecular subtypes-inflammation and proliferation-have been proposed. Recent advances in high-throughput assays using next-generation sequencing have improved our understanding of ICCA pathogenesis and molecular genetics. The diagnosis of ICCA poses a significant challenge for pathologists because of its varied morphologies and phenotypes. Accurate diagnosis of ICCA is essential for effective patient management and prognostic determination. This article provides an updated overview of ICCA pathology, focusing particularly on molecular features, histological subtypes, and diagnostic approaches.

Resection for a Recurrent Mucus-Producing Cholangiocarcinoma After Surgery: a Case Report

Introduction

Intraductal papillary neoplasm of the bile duct (IPNB) is a variant of bile duct carcinoma characterized by intraductal growth. There are few case reports and papers discussing treatment policy and prognosis for cases of postoperative relapse.

Case Presentation

The case subject was a female in her 40s. Due to IPNB with the primary tumor in hepatic left lobe, the patient underwent hepatic left lobe, caudate lobe, and bile duct resection, and biliary tract reconstruction at another institution. Four years later, near the cholangiojejunostomy, a localized recurrence was indicated. Though systemic metastasis was examined with CT, FDG-PET, distant metastasis was not confirmed. As it was believed that resection of the recurrent focal could lead to a long-term survival, the recurrent focal was resected. The resected specimen was a cystic mass with a film, and in a pathologic examination, lymph node tissue was not confirmed in the specimen, while intracystic papilloma of attached liver tissue without continuity was confirmed. The patient has not seen a relapse for 5 years and 5 months after the second surgery.

Conclusion

In a case of localized recurrence after the IPNB surgery, resection should be actively considered.

Recurrent Mutations in APC and CTNNB1 and Activated Wnt/β-catenin Signaling in Intraductal Papillary Neoplasms of the Bile Duct: A Whole Exome Sequencing Study

This study aimed to elucidate the genetic landscape of biliary papillary neoplasms. Of 28 cases examined, 7 underwent whole exome sequencing, while the remaining 21 were used for validation studies with targeted sequencing. In the whole exome sequencing study, 4/7 cases had mutations in either APC or CTNNB1, both of which belong to the Wnt/β-catenin pathway. Somatic mutations were also identified in genes involved in RAS signaling (KRAS, BRAF), a cell cycle regulator (CDC27), histone methyltransferase (KMT2C, KMT2D), and DNA mismatch repair (MSH3, MSH6, PMS1). Combined with discovery and validation cohorts, mutations in APC or CTNNB1 were observed in 6/28 subjects (21%) and were mutually exclusive. When the cases were classified into intraductal papillary neoplasms of the bile duct (IPNBs, n=14) and papillary cholangiocarcinomas (n=14) based on the recently proposed classification criteria, mutations in APC and CTNNB1 appeared to be entirely restricted to IPNBs with 6/14 cases (43%) harboring mutations in either gene. These genetic alterations were detected across the 3 nonintestinal histologic types. In immunohistochemistry, the aberrant cytoplasmic and/or nuclear expression of β-catenin was found in not only 5/6 IPNBs with APC or CTNNB1 mutations, but also 6/8 cases with wild-type APC and CTNNB1 (total 79%). In addition, APC and CTNNB1 alterations were exceptional in nonpapillary cholangiocarcinomas (n=29) with a single case harboring CTNNB1 mutation (3%). This study demonstrated recurrent mutations in APC and CTNNB1 in nonintestinal-type IPNBs, suggesting that activation of the Wnt/β-catenin signaling pathway is relevant to the development and progression of IPNBs.

Mucins: the Old, the New and the Promising Factors in Hepatobiliary Carcinogenesis

Mucins are large O-glycoproteins with high carbohydrate content and marked diversity in both the apoprotein and the oligosaccharide moieties. All three mucin types, trans-membrane (e.g., MUC1, MUC4, MUC16), secreted (gel-forming) (e.g., MUC2, MUC5AC, MUC6) and soluble (non-gel-forming) (e.g., MUC7, MUC8, MUC9, MUC20), are critical in maintaining cellular functions, particularly those of epithelial surfaces. Their aberrant expression and/or altered subcellular localization is a factor of tumour growth and apoptosis induced by oxidative stress and several anti-cancer agents. Abnormal expression of mucins was observed in human carcinomas that arise in various gastrointestinal organs. It was widely believed that hepatocellular carcinoma (HCC) does not produce mucins, whereas cholangiocarcinoma (CC) or combined HCC-CC may produce these glycoproteins. However, a growing number of reports shows that mucins can be produced by HCC cells that do not exhibit or are yet to undergo, morphological differentiation to biliary phenotypes. Evaluation of mucin expression levels in precursors and early lesions of CC, as well as other types of primary liver cancer (PLC), conducted in in vitro and in vivo models, allowed to discover the mechanisms of their action, as well as their participation in the most important signalling pathways of liver cystogenesis and carcinogenesis. Analysis of mucin expression in PLC has both basic research and clinical value. Mucins may act as oncogenes and tumour-promoting (e.g., MUC1, MUC13), and/or tumour-suppressing factors (e.g., MUC15). Given their role in promoting PLC progression, both classic (MUC1, MUC2, MUC4, MUC5AC, MUC6) and currently tested mucins (e.g., MUC13, MUC15, MUC16) have been proposed to be important diagnostic and prognostic markers. The purpose of this review was to summarize and update the role of classic and currently tested mucins in pathogenesis of PLC, with explaining the mechanisms of their action in HCC carcinogenesis. It also focuses on determination of the diagnostic and prognostic role of these glycoproteins in PLC, especially focusing on HCC, CC and other hepatic tumours with- and without biliary differentiation.

Mucin-producing hepatocellular carcinoma without morphological features of biliary differentiation: A case report

RATIONALE

Hepatocellular carcinoma has been believed not to produce mucin unless it has biliary differentiation. However, some cases of hepatocellular carcinoma with extracellular myxoid change have been reported recently, raising the possibility that, in rare cases, hepatocellular carcinoma cells produce mucin.

PATIENT CONCERNS

Here we report a case of hepatocellular carcinoma that contained intracellular and extracellular myxoid matrix without morphological evidence of biliary differentiation, although cells in a portion of the tumor were positive for the epithelial markers cytokeratin 7 and 19. She was brought to our hospital due to abnormal liver tests and a large liver tumor found by ultrasound examination.

DIAGNOSES

The liver tumor showed typical imaging findings of hepatocellular carcinoma.

INTERVENTIONS

The tumor was resected with negative margins, and pathologically diagnosed as hepatocellular carcinoma with mucin production.

OUTCOMES

The patient has been free from recurrence of cancer during two-years' follow-up.

LESSONS

Our case suggests that hepatocellular carcinoma cells can produce mucin without or before morphological differentiation to biliary phenotypes, an observation that may help elucidate the mechanism for the development of combined hepatocellular and cholangiocarcinoma.

Long-term outcome of surgical resection for intraductal papillary neoplasm of the bile duct

BACKGROUND AND AIMS

Intraductal papillary neoplasm of the bile duct (IPNB) is a specific type of bile duct tumor. Studies about the surgical outcomes for IPNB are few; therefore, we investigated the survival of patients who underwent curative surgical resection of IPNB.

METHODS

We retrospectively reviewed the medical and pathological records of 148 IPNB patients who underwent curative-intent hepatic resection between January 2005 and December 2011, to examine the prognosis of IPNB. All demographic and operative parameters were analyzed the effect on survival of patients.

RESULTS

The median survival of IPNB patients was 1326 days with a respective 1, 3, and 5 year overall survival of 83.6% (95%CI: 76.5-88.7), 64.4% (95%CI: 56.0-71.6), and 47% (95%CI: 38.4-55.7). The level of invasiveness of IPNB predicted survival very well. For malignant IPNB, univariate analysis showed that serum CA19-9 level, lymph node metastasis, and completeness of resection were significant prognostic factors. Lymph node metastasis and completeness of resection were found in multivariate analysis to be significantly related to survival of the patients.

CONCLUSIONS

The level of invasiveness and lymph node status were found to be associated with patient survival, as was adequacy of surgery. We recommend R0 resection be attempted for patients with IPNB.

Occult mucin-producing cholangiocarcinoma in situ: a rare clinical case with difficult tumour staging

Background

Mucin-producing cholangiocarcinoma (MPCC) is an uncommon tumour that is clinically characterized by mucin-hypersecretion. Because the initial symptoms of MPCC may be attributed to the viscus mucobilia, the primary tumour mass may potentially be unrecognizable. We report an interesting case of curatively resected occult MPCC in situ.

Case presentation

A 70-year-old man was referred to our hospital with increased levels of biliary enzymes. Multidetector row computed tomography (MDCT) demonstrated a diffuse dilatation of the entire biliary system without evidence of tumour mass. Additionally, there were numerous variably sized cysts throughout the liver. The cyst of S4 was the largest, followed by that of S1, which connected with the right hepatic duct. Endoscopic retrograde cholangiography showed intrabiliary mucus, predominantly in the left hepatic duct, but failed to show a communication of both cysts with the bile duct. We clinically suspected that minute MPCC was present within the S1 cyst and performed left hepatectomy, caudate lobectomy, and resection of the extrahepatic bile duct. Macroscopically, papillary adenocarcinoma in situ was present in the S1 cyst, and a final diagnosis of MPCC originating from the bile duct of the caudate lobe was made.

Conclusions

For MPCC, in practice, we should consider the possibility that this tumour can be occult. In this complicated setting, demonstrating the communication to the responsible dilated duct is a clue to the diagnosis. Multidirectional MDCT images succeeded in specifically demonstrating this communication, which is insensitive to the presence of excessive mucobilia.

Comparative clinicopathological study of biliary intraductal papillary neoplasms and papillary cholangiocarcinomas

AIMS

The aim of this study was to achieve a better definition of intraductal papillary neoplasms of the bile duct (IPNBs).

METHODS AND RESULTS

Biliary tumours that showed predominantly intraductal papillary growth were provisionally classified as IPNBs (n = 25) and papillary cholangiocarcinomas (n = 27). IPNB was defined as a neoplasm that is confined to the epithelium or is regularly arranged in a high-papillary architecture along thin fibrovascular stalks, whereas the term 'papillary cholangiocarcinoma' was used for tumours with more complex papillary structures (e.g. irregular papillary branching or mixed with solid-tubular growth). In our consecutive cohort of biliary neoplasms, 5% were classified as IPNBs, and 10% as papillary cholangiocarcinomas. IPNBs differed from papillary cholangiocarcinomas by less advanced invasion, gross mucin overproduction (72% versus 7%), and their prevalent location (84% of IPNBs in intrahepatic/hilar ducts; 70% of papillary cholangiocarcinomas in extrahepatic ducts). Gastric-type and oncocytic-type tumours were only detected in IPNBs. Expression of mucin core proteins and cytokeratin 20 significantly differed between the two groups. KRAS and GNAS were wild-type genotypes in all but one case of KRAS-mutated IPNB. Patients with IPNB had better recurrence-free survival than those with papillary cholangiocarcinoma (P = 0.007). In multivariate analysis, in which several other prognostic factors (e.g. stromal invasion and lymph node metastasis) were applied, the classification of the two papillary tumours was an independent prognostic factor (P = 0.040).

CONCLUSIONS

Given the significant contrast in clinicopathological features between IPNBs and papillary cholangiocarcinomas, it may be more appropriate to use the diagnostic term 'IPNB' for selected tumours that show regular papillary growth, separately from papillary cholangiocarcinomas.

Pathologic Features of Primary and Metastatic Hepatic Malignancies

In the mammalian liver, 60 % of the cellular components are hepatocytes while the remainder (35 %) includes biliary epithelium, Kupffer cells, endothelial cells, fat storing cells and connective tissue cells. Although neoplasms of hepatocytes are the most common, a significant number of both benign and malignant primary liver neoplasms arising from other cell types can develop, such as tumors of bile duct epithelium (Table 1). In addition, the liver is one of the most susceptible sites for metastatic tumors arising from other organs of the body. Not too long ago, liver tumors were left untreated because the liver was considered a complex and mysterious organ inaccessible to surgery. Advances in imaging procedures and surgical techniques over the past 40 years have revolutionized the approaches to the treatment of benign and malignant liver tumors. Subsegmentectomy, segmentectomy, lobectomy, and transplantation are routinely performed for the treatment of primary and metastatic liver tumors with minimal morbidity and mortality. Since accurate diagnosis remains the key to clinical and surgical management, the emphasis of this chapter is on classification, morphological features and differential diagnosis of malignant neoplasms of the liver.

Clinicopathological significance of mucin production in patients with papillary cholangiocarcinoma

BACKGROUND

The clinicopathologic significance of mucin production in patients with papillary cholangiocarcinoma (PCC) is still controversial. We aimed at clarifying the similarities and differences between PCC cases with and without mucin secretion with regard to biological behavior and clinical course.

METHODS

Among 644 patients with surgically resected cholangiocarcinoma (1998-2011), 184 (28 %) patients were considered to have PCC and were enrolled in the study. Those patients were divided into two groups based on whether their PCC was mucin-producing (PCC-M, n = 89) or not (PCC-NM, n = 95). The presence of mucin secretion was determined by the cut surface of the specimens and by pathologic examination.

RESULTS

The clinicopathological features of PCC-M and PCC-NM largely overlapped. No significant between-group differences in malignant potential characteristics, including the depth of invasion, pathological T classification, and regional/periaortic lymph node metastasis, were observed (P = 0.193, 0.181, 0.083, and 0.674, respectively). However, a few clinicopathological differences existed between the two PCC types, i.e., the predominant histological type and epithelial subtype (P < 0.001 and P = 0.016, respectively). Immunohistochemically, MUC2, MUC5AC, MUC6, and HGM were more frequently expressed in PCC-M than PCC-NM (P < 0.002 in all). The disease-specific survival values were not significantly different between the two PCC types (PCC-M; 60 % at 5 year, PCC-NM; 46 %, P = 0.097).

CONCLUSION

PCC-M and PCC-NM were similar in morphology and prognosis. Although a few clinicopathological differences exist between them, their overlapping features and identical survival curves appear to justify the lack of a specific treatment modality for either type.

A case of biliary cystic tumor with repeated hemobilia

Intraductal papillary neoplasm of the bile duct (IPNB) is classified as a biliary cystic tumor with a tendency of causing obstruction. Neoplastic cases involving hemobilia are rarely reported. We herein describe a case of biliary cystic tumor with repeated hemobilia. A 57-year-old woman was histologically diagnosed with cavernous hemangioma. During the follow-up period after transcatheter arterial embolization (TAE), she experienced repeated hemobilia, and multiple other TAE sessions were performed for hemostasis. She was referred to our hospital 8 years after the first surgery owing to a growing tumor. Histopathological examination after extended right hepatectomy and caudate lobectomy indicated IPNB with an associated invasive carcinoma. Six months thereafter, computed tomography revealed a recurrent liver tumor and a nodule in the abdominal cavity. She died 36 months after the second surgery, despite chemotherapy. Our experience suggests that IPNB should be considered during differential diagnosis of dilated hepatobiliary tumors with hemobilia.

The outcome of ipsilateral hemihepatectomy in mucin-producing bile duct tumors

Background

Mucin-producing bile duct tumors (MPBTs) are unusual, and we present our experience with nine surgically proven cases.

Methods

Between November 2002 and November 2012, 9 patients with surgically proven MPBTs (including history of relevant hepatobiliary surgery in 6 patients) were encountered. Their clinical, imaging, and surgical findings were reviewed.

Results

The most common symptom is intermittent jaundice, which occurs in seven patients. The diagnostic specificity was 77.8% by preoperative Magnetic Resonance Cholangiopancreatography (MRCP). All the patients underwent ipsilateral hemihepatectomy or remnant hemihepatectomy, accompanied caudate lobectomy in one case and concomitant Roux-en-Y choledochojejunostomy in four cases. Postoperative course was uneventful. One patient, who had intra-abdominal recurrence 59 months after surgery, was received reoperation without recurrence at the last follow-up. The remaining eight patients were alive without disease recurrence.

Conclusion

Based on our follow up of 9 cases that were surgically treated for MPBTs, we conclude that ipsilateral hemihepatectomy is a safe surgical procedure with an observed recurrence risk of 11.1% and all long-term survival.

Intraductal papillary neoplasms of the bile duct

Intraductal papillary neoplasm of the bile duct (IPNB) is a rare variant of bile duct tumors characterized by papillary growth within the bile duct lumen and is regarded as a biliary counterpart of intraductal papillary mucinous neoplasm of the pancreas. IPNBs display a spectrum of premalignant lesion towards invasive cholangiocarcinoma. The most common radiologic findings for IPNB are bile duct dilatation and intraductal masses. The major treatment of IPNB is surgical resection. Ultrasonography, computed tomography, magnetic resonance image, and cholangiography are usually performed to assess tumor location and extension. Cholangioscopy can confirm the histology and assess the extent of the tumor including superficial spreading along the biliary epithelium. However, pathologic diagnosis by preoperative biopsy cannot always reflect the maximum degree of atypia, because IPNBs are often composed of varying degrees of cytoarchitectural atypia. IPNBs are microscopically classified into four epithelial subtypes, such as pancreatobiliary, intestinal, gastric, and oncocytic types. Most cases of IPNB are IPN with high-grade intraepithelial neoplasia or with an associated invasive carcinoma. The histologic types of invasive lesions are either tubular adenocarcinoma or mucinous carcinoma. Although several authors have investigated molecular genetic changes during the development and progression of IPNB, these are still poorly characterized and controversial.

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.

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.

Diagnosis and treatment of mucobilia: A review and analysis of 80 cases

AIM: To discuss the epidemiology, diagnosis, and treatment of mucobilia in China to provide a reference for clinicians.

METHODS: All statistical data were obtained from the available literature. Non-overlapping cases were all selected, while cases with the longest time span or with the largest number were selected when overlapping cases existed. A total of 12 papers were included, and 4 of them reported more than 5 cases. The largest number of cases in a single paper is 22.

RESULTS: A total of 12 qualified papers reporting 80 cases of mucobilia were included. Preoperative diagnosis of mucobilia is difficult. The rate of misdiagnosis reached 48%, and mucobilia has no significant specificity compared with some diseases presenting with benign and malignant obstructive jaundice. The annual mortality rate was 16.44%. Preoperative diagnosis mainly depends on clinical presentation and ultrasound, CT, ERCP, PTC and other auxiliary examinations. If intraoperative bile duct exploration reveals a large amount of jelly-like mucus in the cavity, a diagnosis of mucobilia can be established.

CONCLUSION: Mucobilia is a rare biliary disease having many causes such as inflammation of the bile duct and carcinoma of the bile duct. The location, extent and nature of the primary disease can be confirmed by choledochofiberscopy and biopsy. Preferred treatment is a complete resection of primary lesions to ensure both good and smooth drainage of the bile duct.

Intraductal papillary mucininous neoplasm of the bile ducts: multimodality assessment with pathologic correlation

Mucin-producing intraductal papillary neoplasm (adenocarcinoma/adenoma) in the bile duct is becoming recognized as a specific type of neoplasm. Since, it bears a striking similarity to intraductal papillary mucinous neoplasms of the pancreas with regard to its histopathologic features, the term "intraductal papillary mucinous neoplasms of the bile duct" (IPMN-B) is frequently used, although no definite terminology or definition has been decided by World Health Organization. This neoplasm lacks ovarian-like stroma and communicates with the bile ducts, unlike biliary mucinous cystic neoplasm (MCN). On the other hand, malignant IPMN-B is categorized as an intraductal-growth type of intrahepatic cholangiocarcinoma (ICC). In comparison to other types of ICC, such as the mass-forming type and periductal-infiltrating type that have poor resectability and an unfavorable prognosis, malignant IPMN-B can be resected and demonstrates a more favorable prognosis. Meanwhile, unlike biliary MCN that is usually confined in a closed cyst, IPMN-B can spread along the mucosal surface of the bile ducts, and it should be widely resected. Therefore, multimodality assessment is needed to ensure the correct diagnosis of IPMN-B. We herein review the imaging findings of IPMN-B with pathologic correlation.

Mucin-producing intrahepatic biliary papillomatosis

PURPOSE

Mucin-producing intrahepatic biliary papillomatosis (MPIBP) is an uncommon tumor. The purpose of this study was to evaluate the clinical, radiological, and histopathological characteristics of MPIBP, and its prognosis.

METHODS

A retrospective analysis was conducted of 11 patients who underwent surgery for MPIBP. The clinical features and radiological, pathological, and operative findings were reviewed, and the survival rates were determined.

RESULTS

Repeated episodes of fever and epigastric pain with or without jaundice were the common clinical manifestations. Radiologically, all patients showed diffuse bile duct dilatation with cystic change in intrahepatic bile duct. All patients underwent a hepatic resection with or without an extrahepatic bile duct resection. No in-hospital mortality occurred. All patients survived without any signs of recurrence (median 12 +/- 7 months); three patients, including two patients who underwent a palliative resection, had an attack of cholangitis, which was effectively treated with antibiotics.

CONCLUSIONS

A diagnosis of MPIBP is usually made in patients with biliary dilatation following a radiologic study. Magnetic resonance cholangiopancreatography is more valuable than other modalities in diagnosis. Mucin-producing intrahepatic biliary papillomatosis is a premalignant disease with high malignant potential. The prognosis of MPIBP is excellent if an aggressive resection is performed. A combination of cholangioscopy and frozen sections during the operation is beneficial for a radical successful surgical resection.

A huge intraductal papillary mucinous carcinoma of the bile duct treated by right trisectionectomy with caudate lobectomy

Background

Because intraductal papillary mucinous neoplasm of the bile duct (IPMN-B) is believed to show a better clinical course than non-papillary biliary neoplasms, it is important to make a precise diagnosis and to perform complete surgical resection.

Case presentation

We herein report a case of malignant IPMN-B treated by right trisectionectomy with caudate lobectomy and extrahepatic bile duct resection. Radiologic images showed marked dilatation of the left medial sectional bile duct (B4) resulting in a bulky cystic mass with multiple internal papillary projections. Duodenal endoscopic examination demonstrated very patulous ampullary orifice with mucin expulsion and endoscopic retrograde cholangiogram confirmed marked cystic dilatation of B4 with luminal filling defects. These findings suggested IPMN-B with malignancy potential. The functional volume of the left lateral section was estimated to be 45%. A planned extensive surgery was successfully performed. The remnant bile ducts were also dilated but had no macroscopic intraluminal tumorous lesion. The histopathological examination yielded the diagnosis of mucin-producing oncocytic intraductal papillary carcinoma of the bile duct with poorly differentiated carcinomas showing neuroendocrine differentiation. The tumor was 14.0 × 13.0 cm-sized and revealed no stromal invasiveness. Resection margins of the proximal bile duct and hepatic parenchyma were free of tumor cell. The patient showed no postoperative complication and was discharged on 10^th postoperative date. He has been regularly followed at outpatient department with no evidence of recurrence.

Conclusion

Considering a favorable prognosis of IPMN-B compared to non-papillary biliary neoplasms, this tumor can be a good indication for aggressive surgical resection regardless of its tumor size.

Surgical strategy for mucin-producing bile duct tumor

Tumors with copious mucin production within the intra- or extrahepatic bile ducts have been reported as mucin-producing bile duct tumors (MPBTs). Because mucin produced by these tumors causes recurrent cholangitis and obstructive jaundice, surgical resection should be indicated even if these tumors are regarded as benign. In order to choose the appropriate surgical procedure, exact preoperative assessment of tumor location and cancer extension is important, especially evaluation of the extent of superficial spreading through cholangioscopic observation and biopsy. In principle, MPBTs should be resected in a manner similar to that employed for other types of bile duct carcinomas. That is, major hepatectomy with or without extrahepatic bile duct resection or pancreaticoduodenectomy should be chosen as the surgical procedure, and intraoperative frozen section at the stumps of the bile duct is essential. On the other hand, when precise diagnosis is completed preoperatively and the lesion is diagnosed as adenoma or carcinoma with invasion confined to the ductal wall and limited superficial spreading, limited resections preserving organ functions as much as possible can be considered as a choice among surgical procedures. All ten patients with MPBT resected at our institution according to these strategies are still alive without tumor recurrence, with a median survival of 48.0 months.

Molecular mechanisms of cholangiocarcinogenesis: are biliary intraepithelial neoplasia and intraductal papillary neoplasms of the bile duct precursors to cholangiocarcinoma?

Cholangiocarcinoma (CC) is a rare, malignant neoplasm that can develop from any site within the intrahepatic or extrahepatic biliary tree. Although the key steps of cholangiocarcinogenesis remain unknown, it has been hypothesized that CC may develop through two key premalignant precursor lesions: biliary intraepithelial neoplasia (BilIN) and intraductal papillary neoplasm of the bile duct (IPNB). These lesions probably are analogous to pancreatic intraepithelial neoplasia and intraductal papillary mucinous neoplasm, respectively. This article outlines the molecular basis of cholangiocarcinogenesis through the BilIN and IPNB pathways. It highlights the genetic mutations that alter cellular proliferation, tumor suppression, and impairment of critical mucinous, cell-adhesion, and matrix proteins.

A comparison of hepatic mucinous cystic neoplasms with biliary intraductal papillary neoplasms

BACKGROUND & AIMS

There is controversy regarding the term biliary intraductal papillary neoplasms (IPN-B) and their pathology, which frequently are confused with hepatic mucinous cystic neoplasms (MCN). We aimed to summarize the clinicopathologic features of IPN-B and differentiate them from MCN.

METHODS

From January 1998 to December 2007, there were 19 patients with intrahepatic IPN-B and 13 patients with MCN who underwent surgical treatment at Zhongshan Hospital. Multiple demographic and clinicopathologic parameters were reviewed retrospectively and compared between the groups.

RESULTS

The mean ages of patients with IPN-B and MCN were 59.5 +/- 11.1 and 44.4 +/- 9.7 years, respectively (P = .0004); the male:female ratios also differed (11:8 vs 2:11; P = .028). Tumors were significantly smaller (6.0 vs 11.2 cm; P = .006) in patients with IPN-B than in those with MCN. More patients with IPN-B also had hepatolithiasis (47.4% vs 0%, P = .004); cholangiectasis and communication between the cyst and main bile duct were more frequent in patients with IPN-B than in those with MCN (P < .001). The IPN-B consisted of 4 subtypes--the gastric subtype was the least invasive. Malignant lesions were more common in patients with IPN-B than in those with MCN (78.9% vs 38.5%; P = .03). The overall 5-year survival rates of patients with IPN-B and MCN were 82% and 100%, respectively.

CONCLUSIONS

Intrahepatic IPN-B represents a distinct clinicopathologic entity that differs clinically, histologically, and radiologically from MCN. Curative resection has a favorable prognosis for patients with IPN-B, but further studies of its subtype are required.

Intraductal oncocytic papillary neoplasm of the bile duct: the first case of peribiliary gland origin

We report herein the first case of intraductal oncocytic papillary neoplasm of the bile duct arising from a peribiliary gland of the left hepatic duct. The patient was a 63-year-old Japanese man. Radiological and cholangioscopic examinations revealed intraductal tumor of the left hepatic duct. After pathological diagnosis of adenocarcinoma by cholangioscopic biopsy, a surgical hepatobiliary resection was performed. Pathological examination revealed papillary tumor in the left hepatic duct. Histologically, the tumor was identified as papillary neoplasm comprising oncocytic cells and delicate fibrovascular cores. Interestingly, this tumor originated from the cystic space in the bile duct wall. This cystic space was histologically identified as a cystically dilated peribiliary gland. Carcinoma in situ was observed in this cystic peribiliary gland at the bottom of the tumor, but not on any areas of biliary epithelium. This case suggests that intraductal papillary neoplasm can arise from both biliary epithelium and peribiliary glands.

Endoscopic retrograde cholangiography in the diagnosis and treatment of mucobilia

OBJECTIVE

Some biliary neoplasms secrete copious mucin into bile ducts, yet the management of mucobilia is not well known. The objective of this study was to analyze 16 patients with copious mucin in the biliary tract stressing the diagnostic and therapeutic aspects of endoscopic retrograde cholangiography (ERC).

MATERIAL AND METHODS

Sixteen patients with mucobilia were found among 5635 cases of ERC from October 1999 to October 2006 in our institution. Diagnostic and therapeutic ERC as well as clinical features were retrospectively analyzed.

RESULTS

Mucin had a greater impact than the neoplasm itself on the cholangiogram and clinical presentation. ERC failed to show the tumors but a disproportionate or aneurysmal dilatation of the segmental or lobar duct correlated with the tumor-bearing duct was evident. Endoscopic managements included clearance of intraductal mucin and/or endoscopic nasobiliary drainage (ENBD). Three patients were excluded from outcome assessment because of non-specific symptoms or spontaneously subsiding jaundice. Among the 13 patients eligible for assessment, subjective improvement in symptoms and/or a decrease in jaundice along with subsiding cholangitis following ERC was observed in 5 of the 7 patients that underwent both clearance of intraductal mucin and ENBD (ENBD function was poor in all 7 patients), in 1 patient who underwent only clearance of intraductal mucin, and in 3 of the 5 patients who underwent only ENBD. The three patients with progressive jaundice, despite endoscopic management, had advanced disease.

CONCLUSIONS

ERC revealed the tumor-bearing duct but not the extent of the disease in most of the patients with mucobilia. When mucobilia is encountered during ERC, the management should include clearance of as much intraductal mucin as possible. ENBD is frequently obstructed by mucin and may be helpful only in selected cases.

Left hemihepatectomy and caudate lobectomy and complete extrahepatic bile duct resection using transduodenal approach for hilar cholangiocarcinoma arsing from biliary papillomatosis

BACKGROUND

Biliary papillomatosis (BP) is a rare disease characterized by multiple papillary lesions of variable distribution and extent in the intra and extrahepatic bile duct. Hepatopancreatoduodenectomy (HPD) can be indicated for the resection of diffuse intra and extrahepatic BP that extended to the distal bile duct and ampullary region. The mortality rate for HPD has recently decreased but HPD still has a high morbidity rate. In this study, we present a safe procedure for concomitant intrahepatic and extrahepatic BP.

PATIENTS AND METHODS

Preoperative studies showed showed multiple, variable-sized, and nodular papillary masses with mucin in the left intrahepatic ducts, confluence of the right and left hepatic ducts, common hepatic duct, and whole CBD, but peripheral to the right intrahepatic bile ducts were grossly well preserved. We underwent Lt. hepatectomy and the common bile duct and ampulla of Vater were completely resected with transduodenal approach and the pancreatic duct was repositioned to the duodenal mucosa.

CONCLUSIONS

Major hepatic resection and transduodenal approach for complete bile duct resection and pancreatic duct repositioning could be an acceptable therapeutic option for concomitant intrahepatic and extrahepatic biliary papillomatosis without the evidence of pancreatic duct involvement in the patients with severe comorbidity.

Intraductal papillary neoplasm of the bile ducts: the clinical features and surgical outcome of 25 cases

BACKGROUND AND OBJECTIVES

Intraductal papillary neoplasm of the bile ducts (IPN-B) is considered an uncommon tumor. The purpose of this study was to evaluate the clinical, radiological, and histopathological characteristics of IPN-B, and its prognosis.

METHODS

From October 1995 to August 2006, a retrospective analysis was made of 25 patients that underwent surgery for IPN-B. Clinical features and radiological, pathological, and operative findings were reviewed, and survival rates were determined.

RESULTS

In five patients (20.0%), lesions were incidentally found. Radiologically, 23 of the 25 (92.0%) showed bile duct dilatation, bile duct dilatation with or without an intraductal mass, and cystic changes of bile ducts. Twenty three of the 25 patients underwent hepatic resection with or without extrahepatic bile duct resection. No in hospital mortality occurred. Median survival time of resected patients was 59.8 months and 1-, 2-, and 4-year survival rates were 90.5%, 84.0%, and 84.0%, respectively. All six patients with benign IPN-B remained alive at a mean of 26.2 postoperative months without recurrence.

CONCLUSIONS

A diagnosis of IPN-B is usually made in patients with biliary dilatation by radiologic study. The prognosis of IPN-B, especially of the benign category, is excellent. Aggressive surgical resection is the treatment of choice for IPN-B.

Mucin-producing bile duct tumor of the caudate lobe protruding into the common hepatic duct

Mucin-producing tumor in the bile duct is referred to clinically as mucin-producing bile duct tumor (MPBT). Intraductal papillary neoplasm of the biliary tract that resembles an intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a rare category of MPBT and is not well characterized. We, herein, report a case of MPBT of the caudate lobe of the liver that showed papillary growth and communicated with the bile duct of the caudate lobe and protruded into the common hepatic duct. Histologically, MPBT cells showed papillary overgrowth with abundant mucinous secretions, resembling an IPMN of the pancreas. The MPBT cells showed the same immunostaining pattern as that of cells from IPMN of the pancreas.

Intraductal growth-type mucin-producing peripheral cholangiocarcinoma associated with biliary papillomatosis

A 64-year-old woman with upper abdominal pain, nausea, and vomiting was admitted. The magnetic resonance imaging revealed marked dilation and "crowding" of the segment 4 bile ducts with an area suspicious for a stone or tumor. Ultrasonography-guided percutaneous transhepatic cholangiography revealed multiple filling defects in the segment 4 bile ducts, the left and common hepatic ducts. A left hepatectomy and cholecystectomy was performed. Dilated bile ducts containing mucinous material and a mass in the cystically dilated bile ducts of segment 4 were detected in the gross examination. It showed continuity within the surrounding dilated bile ducts. The dilated bile ducts of the segments 2 and 3 contained mucinous material without any apparent mass formation. Microscopically, the bile ducts were lined by biliary epithelium displaying simple and complex papillary structures with moderate to severe degree of dysplastic changes. The mass was composed of complex papillary structures filling the bile duct with a few foci of invasion. The papillary structures were composed of mucin-producing columnar cells as well as cells with oncocytic appearance. Patchy cytokeratin 7, cytokeratin 19, hepatocyte paraffin 1, MUC2, and CDX2 immunopositivities were observed. Biliary papillomatosis, mucin-producing intrahepatic cholangiocarcinoma, and intraductal papillary-type peripheral cholangiocarcinoma are in the same disease spectrum of papillary biliary neoplasm and termed as intraductal papillary neoplasm of the liver. Mucinous hypersecretion and signs of mucobilia are considered specific and should raise the suspicion of lesions in this spectrum.

Cholangiographic spectrum of intraductal papillary mucinous neoplasm of the bile ducts

OBJECTIVE

To propose a cholangiographic classification for intraductal growth type intrahepatic cholangiocarcinoma (IG-ICC) and its precursor, collectively termed intraductal papillary mucinous neoplasm of the bile ducts (IPMN-B).

SUMMARY BACKGROUND DATA

For the extensive clinicopathologic variations of IPMN-B, a detailed characterization of cholangiography for IPMN-B is beneficial for determining the optimal therapeutic strategy.

METHODS

A total of 124 patients with cholangiography-available and pathologically proven IPMN-B were retrospectively studied. Numbers of IPMN-B type 1, type 2, type 3, and type 4 were 33, 17, 15, and 59, respectively. A cholangiographic classification was proposed based on the presence of hepatolithiasis, mucobilia, neoplasia localization, and concomitant malignancies. The demographics, histologic grading, management, and survival were also analyzed.

RESULTS

All 33 IPMN-B type 1 and 12 of 17 IPMN-B type 2 displayed cholangiographic pattern IA demonstrating hepatolithiasis-related biliary stricture. The remaining 5 IPMN-B type 2 displayed cholangiographic pattern IB or IC, which demonstrated mucobilia without discernible neoplasia. Seven of 15 IPMN-B type 3 and 52 of the 59 IPMN-B type 4 displayed cholangiographic pattern IIA or IIB, which demonstrated overt intraductal neoplasia. Seven IPMN-B type 3 or 4 displayed cholangiographic pattern IIIA or IIIB, which demonstrated IPMN-B and concomitant malignancies. For those presenting with cholangiographic pattern IA, IC, IIA, IIB, and IIIA, straightforward hepatectomies for the diseased lobes were performed. For those with pattern IB, surgical resections were performed only when there was emergence of mucin-producing neoplasia. For those with IIIB, the concomitant malignancies were considered inoperable. No disease-related death occurred in IPMN-B type 1and 2. The mean survival rates of IPMN-B type 3 and type 4 were 55.5 +/- 17.1 months and 36.9 +/- 6.3 months, respectively.

CONCLUSION

The presented cholangiographic classification facilitates the management for IPMN-B. Significant survival discrepancy at the various stages warrants a more aggressive surgical strategy.

Clinicopathological factors predicting long-term overall survival after hepatectomy for peripheral cholangiocarcinoma

Peripheral cholangiocarcinoma (PCC) is clinically challenging because patients typically do not present until the disease is relatively advanced. Three-year to 5-year survival rates even with resection thus remain dismal. This study aimed to determine the clinicopathological factors for predicting overall survival longer than 5 years in PCC patients treated with hepatectomy. From 1977 to 1997, the clinicopatholgical features of 11 PCC patients who underwent hepatectomy with long-term overall survival (group A) were reviewed. Comparison was made with the clinical features and factors influencing the outcome of 70 PCC patients who survived less than 5 years after hepatectomy (group B). Of 81 PCC patients undergoing hepatectomy, 11 (13.6%) were 5-year survivors. The 81 PCC patients comprised 32 men and 49 women, with a mean age of 56.0 years (range: 34-83 years). Univariate analysis showed that female gender, absence of physical findings, a higher percentage of presence of mucobilia, early staged tumor, intraductal papillary tumor growth, and curative hepatic resection were more frequent in group A patients than group B patients. However, multivariate logistic regression analysis showed that absence of physical findings, presence of mucobilia, early staged tumor, and curative hepatic resection were the four independent factors differentiating group A from B patients. The 1-, 3-, 5-, and 10-year survival rates of the group A patients were 100%, 100%, 100%, and 40%, whereas those of the group B patients were 46.0%, 9.5%, 0%, and 0%, respectively. Absence of physical findings, presence of mucobilia, early staged tumor, and curative hepatectomy could independently predict PCC patients with long-term overall survival after hepatectomy.

Characterization of intrahepatic cholangiocarcinoma of the intraductal growth-type and its precursor lesions

A cohort of patients with intraductal growth-type intrahepatic cholangiocarcinoma (IG-ICC) and its precursor lesions, collectively termed intraductal papillary neoplasm of the liver (IPNL), was characterized with respect to demographics, clinical manifestations, perioperative management, long-term survival, and molecular features associated with carcinogenesis. A total of 122 patients with IPNL types 1 through 4, 108 patients with non-IG-ICC and 210 patients with hepatolithiasis alone were studied. Expression of CDX2, TFF1, MUC1, MUC2, MUC5AC, EGFR, and p53 was determined by using immunohistochemistry. Females predominated in those with hepatolithiasis alone and IPNL. The mean age of patients with hepatolithiasis alone was 6 to 8 years younger than that of those with IPNL. The association with hepatolithiasis in patients with IPNL types 1 and 2, IPNL types 3 and 4, and non-IG-ICC was 100%, 79%, and 64%, respectively. Mucobilia, anemia, and elevated serum carcinoembryonic antigen levels were helpful in distinguishing IG-ICC and its precursor lesions. The mean survival of patients with IPNL type 3, IPNL type 4, and non-IG-ICC was 55.5 months, 36.9 months, and 15.8 months, respectively. The incidence of expression of CDX2 and TFF1 was maximal in IPNL type 3. Expression and cellular distribution of MUC2 and CDX2 were similar. MUC5AC was strongly expressed in all patients with IPNL; EGFR and p53 were rarely expressed in patients with IPNL. In conclusion, hepatolithiasis appears to be a precipitating factor in the development of IPNL. Signs of mucobilia were specific for the diagnosis of IPNL. Expression of CDX2 and MUC2 are helpful in differentiating IPNL and non-IG-ICC. Significant differences in survival associated with the various lesions studied warrants a more aggressive surgical strategy in their management.

Intrahepatic cholangiocarcinoma escapes from growth inhibitory effect of transforming growth factor-beta1 by overexpression of cyclin D1

Transforming growth factor-beta1 (TGF-beta1) is involved in tumor progression by promoting angiogenesis or suppressing the immune system; yet TGF-beta1 also has a growth-inhibitory effect on epithelial cells including carcinoma cells. Several mechanisms of impaired TGF-beta1 responsiveness of carcinoma cells have been reported. In this study, we examined how TGF-beta1 participates in the development and progression of intrahepatic cholangiocarcinoma (ICC) associated with hepatolithiasis, and how ICC cells escape from growth inhibitory effect of TGF-beta1. A total of 40 cases of hepatolithiasis were studied, including 16 cases of ICC, and in vitro studies were conducted with cultured murine non-neoplastic biliary epithelial cells (MBEC) and three ICC cell lines. Immunohistochemically, TGF-beta1 was expressed in mononuclear cells and mesenchymal cells around the stone-containing bile ducts and invasive ICC, and also in biliary epithelial cells (hyperplastic and precursor lesions, and ICC). TGF-beta type II receptor (TbetaR-II) was constantly expressed on biliary epithelial cells irrespective of biliary lesions. In cell culture studies, TGF-beta1 significantly inhibited proliferation of MBEC via downregulation of cyclin D1, cdk4, and cdk6, while TGF-beta1 did not influence the proliferation of ICC cells. After suppression of cyclin D1 expression in one ICC cell line using cyclin D1 small interfering RNA, TGF-beta1 significantly inhibited the proliferation of ICC cells. In conclusion, high levels of TGF-beta1 around ICC or its precursors may be involved in development and progression of ICC in hepatolithiasis. ICC cells could escape the growth inhibitory effect of TGF-beta1 by overexpression of cyclin D1.

Prognostic analysis of surgical treatment of peripheral cholangiocarcinoma: Two decades of experience at Chang Gung Memorial Hospital

AIM: To analyze the prognostic factors influencing the overall survival of peripheral cholangiocarcinoma (PCC) patients undergoing surgical treatment during 25 years at a single institution.

METHODS: This study retrospectively reviewed prospectively collecting data about 373 patients with histologically proven PCC who underwent surgical treatment between 1977 and 2001.

RESULTS: Three hundred and seventy-three PCC patients (159 men and 214 women) underwent surgical treatment from 1977 to 2001. Among them, 187 PCC patients underwent hepatectomy and 135 had curative resection (curative resectability rate: 36.2%). The follow-up duration ranged from 1.05 to 167.6 mo (mean/median = 14.1/7.2 mo). Overall cumulative survival rates at 1, 3, and 5 years were 32.5%, 9.2%, and 4.1%, respectively. Univariate log-rank analysis identified the following as adverse influences on overall survival: presence of symptoms, absence of mucobilia, elevated CEA and CA 19-9 levels, non-papillary tumor type, receiving non-hepatectomy, advanced tumor staging, lack of post-operative chemotherapy, and radiotherapy. Meanwhile, multivariate Cox’s proportional hazard analysis demonstrated that absence of mucobilia, non-papillary tumor type, advanced tumor staging, non-hepatectomy, and lack of post-operative chemotherapy were the five independent prognostic factors that adversely affected overall survival.

CONCLUSION: Favorable overall survival of PCC patients undergoing surgical treatment depends on early tumor stage, presence of mucobilia, papillary tumor type, hepatic resection, and post-operative chemotherapy.

Hepatic resection of the intraductal papillary type of peripheral cholangiocarcinoma

BACKGROUND

Peripheral cholangiocarcinoma (PCC) can be grossly classified into mass-forming, periductal-infiltrating, and intraductal papillary (IP) types. Information on IP-PCC patients undergoing hepatectomy is sparse because of the small number of cases.

METHODS

The clinical features of 40 IP-PCC patients undergoing hepatectomy between 1977 and 2000 were reviewed. The clinical features of 94 PCC patients without IP growth undergoing hepatectomy were used for comparison.

RESULTS

IP-PCC and non-IP-PCC groups had similar age distributions (P =.674), sex ratios (P =.079), and positive rates for serum carcinoembryonic antigen and CA 19-9 (P =.121 and.795, respectively). The two groups also exhibited similar rates of association between hepatolithiasis and PCC (P =.230). However, more IP-PCC patients exhibited signs during admission, and more had ALT values >36 IU/L; they also had smaller tumors, more mucobilia association, and tumors in earlier stages and had undergone more postoperative chemotherapy. Multivariate logistic regression analysis showed that only ALT >36 IU/L differentiated IP-PCC from non-IP-PCC patients. The two groups exhibited similar operative mortality (P = 1.0). Follow-up ranged from 1.6 to 125.2 months (mean and median, 44.6 and 5.7 months, respectively). The 1-, 3-, and 5-year overall survival rates were 72.9%, 41.2%, and 24.7%, respectively, in the IP-PCC group and 43.3, 6.03%, and 2.01% in the non-IP-PCC group. The prognosis was favorable for the IP-PCC patients (P <.00001), particularly for IP-PCC patients who received curative hepatectomy (P =.013).

CONCLUSIONS

IP-PCC patients had significantly better survival than non-IP-PCC patients, and aggressive curative hepatic resection is associated with a longer survival.

Expression of epidermal growth factor receptor, apomucins, matrix metalloproteinases, and p53 in rat and human cholangiocarcinoma: appraisal of an animal model of cholangiocarcinoma

OBJECTIVE

We sought to determine the expression of molecular markers in an animal model of cholangiocarcinoma compared with those in human cholangiocarcinoma.

SUMMARY BACKGROUND DATA

Cholangiocarcinoma is a rare disease characterized by early intrahepatic and extrahepatic spread, which seriously limits the efficacy of surgery. Establishing an experimental model to study the cholangiocarcinogenesis is desirable.

METHODS

Sprague-Dawley rats weighing 300 +/- 50 g were used for the study group. The animals were given 0.3% thioacetamide in tap water continuously. Thirty mass-forming peripheral cholangiocarcinoma patients also were studied. Expression of epidermal growth factor receptor (EGFR), MUC1, MUC2, MUC5AC, MMP-2, MMP-9, and p53 in both human and experimental rat cholangiocarcinoma was examined using immunohistochemistry.

RESULTS

Using thioacetamide 0.3% as a hepatoxin to induce cholangiocarcinoma in rats, microfoci of cancerous cells were detected from 12 weeks, and all experimental rats displayed diffuse mass-forming cholangiocarcinoma after 24 weeks. EGFR was strongly expressed in 14 (47%) of 30 human cholangiocarcinoms and 24 (100%) of 24 rat cholangiocarcinomas, respectively. MUC1 was strongly expressed in all human and rat cholangiocarcinomas, whereas MUC2 and MUC5AC were focally and weakly expressed. MMP-2 and MMP-9 were strongly expressed in 22 (73%) of 30 human cholangiocarcinomas and 24 (100%) of 24 rat cholangiocarcinomas, respectively. p53 overexpression was detected in 9 (30%) of 30 human cholangiocarcinoma and none of the rat cholangiocarcinoma, respectively.

CONCLUSIONS

The expression of EGFR, apomucins, MMPs, and p53 in rat cholangiocarcinoma was strongly homologous to human cholangiocarcinoma. Thioacetamide-induced cholangiocarcinoma in rats provides an excellent model for investigating cholangiocarcinogenesis in vivo.

Intraductal papillary mucinous tumor of the bile ducts

Papillary tumors of the bile ducts are intraductal tumors with numerous minute frondlike papillary projections. Some intraductal papillary tumors of the bile ducts produce a large amount of mucin that disturbs bile flow and causes severe biliary dilatation. In the presence of a tumor of this subgroup, the entire biliary tree is dilated; segmental or lobar bile ducts are dilated disproportionately, and aneurysmal dilatation may occur. Mucin is depicted at cholangiography as multiple elongated or cordlike filling defects, and the tumor is depicted on cross-sectional images as a castlike, polypoid, or fungating mass in the dilated biliary tree. Based on these characteristic imaging features-dilatation, mucin, and tumor-correct diagnosis of intraductal papillary mucinous tumor of the bile ducts may be made.

Pathologic features of mucin-producing bile duct tumors: two histopathologic categories as counterparts of pancreatic intraductal papillary-mucinous neoplasms

Tumors with clinically recognizable mucin production arising from bile duct, "mucin-producing bile duct tumors (MPBTs)," have not been studied yet for their pathologic features and classification in details. The clinical findings of MPBT have a lot of similarities to those of pancreatic intraductal papillary-mucinous neoplasm. In the present study, we examined 30 MPBTs and classified them into two distinct morphologic categories: 22 cases of "columnar type" composed of pseudostratified columnar cells with basophilic cytoplasm and columnar nuclei and 8 cases of "cuboidal type" composed of pancreaticobiliary and/or oncocytic pattern. Pancreaticobiliary pattern showed abundantly branched papillae lined by acidophilic cuboidal cells with round nuclei, whereas oncocytic pattern was characterized by intraepithelial lumina and cribriform pattern composed of abundant oxyphilic cells with round nuclei, and these patterns overlapped frequently. There were significant differences in the clinicopathologic findings including macroscopic findings, morphometric data, mucin expression profiles (MUC2 expression in columnar type and MUC6 expression in cuboidal type), and cell proliferative activities between columnar type and cuboidal type. Patients with columnar type showed significantly poorer survival than those with cuboidal type. We concluded that columnar type and cuboidal type of MBPTs belong to different lineage of neoplasm and that they are counterparts of "intestinal type" and "pancreaticobiliary type" of pancreatic intraductal papillary-mucinous neoplasm, respectively.

Aberrant expression of CDX2 is closely related to the intestinal metaplasia and MUC2 expression in intraductal papillary neoplasm of the liver in hepatolithiasis

Intraductal papillary neoplasia of the liver (IPNL) frequently presents gastrointestinal metaplasia with aberrant expression of MUC2 and MUC5AC and oversecretion of mucin into the ductal lumen. In this study, the involvement of CDX2, a homeodomain protein involved in the regulation of intestinal development and differentiation, in the expression of MUC2 was examined in mucinous intrahepatic cholangiocarcinoma (ICC) (n=7) and IPNL with hepatolithiasis (n=19) with comparison to conventional ICC (n=11), and intraductal papillary mucinous tumor and invasive ductal carcinoma of the pancreas (n=9 and 11, respectively). A total of 33 cases of hepatolithiasis, extrahepatic biliary obstruction and normal livers were used as the control. Immunohistochemically, both MUC2 and MUC5AC were frequently expressed in mucinous ICC and IPNL, while expression of MUC2 was not seen in conventional ICC. The nuclear expression of CDX2 was closely associated with the expression of MUC2 in mucinous ICC and IPNL. This intimate association of MUC2 and CDX2 was confirmed by double immunostaining. The cytoplasmic CDX2 expression was frequent in the mucinous and the conventional ICC and pancreatic carcinoma, irrespective of MUC2 and MUC5AC expression. CDX2 mRNA was detected in neoplastic cells showing cytoplasmic as well as nuclear expression of CDX2 by reverse transcriptase-polymerase chain reaction. One IPMT expressed MUC2 associated with nuclear CDX2 expression, while the other IPMT and conventional pancreatic carcinoma expressed MUC5AC only. Aberrant expression of CDX2 is closely related to the overexpression of MUC2 in mucinous ICC and IPNL associated with hepatolithiasia, suggesting its role in intestinal differentiation and its association with carcinogenesis in these tumors.

Influence of age on surgical treatment of peripheral cholangiocarcinoma

BACKGROUND

Peripheral cholangiocarcinoma (PCC) constitutes the second most common primary liver cancer. Information is lacking on patients with PCC <40 years old undergoing surgical treatment. The aim of this study was to evaluate the influence of age on surgical treatment of patients with PCC based on reviewing the clinicopathologic features and survival rate of 23 patients with PCC <40 years old who received surgical treatment.

METHODS

The clinical features of 23 younger patients with PCC (<40 years old) who underwent surgical treatment between 1977 and 2000 were reviewed. Clinical features of 284 patients with PCC >40 years old were used for comparison.

RESULTS

Three hundred seven patients with PCC with an age range between 28 and 93 years (mean 57.2, median 56.0) were investigated. The fiftieth decade was the peak PCC age in the series. Clinical presentations and physical findings were similar between younger and older PCC groups. Similar positive serum carcinoembryonic antigen and carbohydrate antigen 19-9 rates (42.9% and 66.7% vs 41.2% and 74.4%, respectively) and a similar rate of hepatolithiasis associated with PCC were also observed between the 2 groups (43.5% vs 48.9%). Younger patients with PCC tended to show less mucobilia, less papillary-type PCC, and a more advanced stage of tumor compared with older patients with PCC. However, postoperative adjuvant chemotherapy and radiotherapy were used more frequently in the older patients with PCC. Operative morbidity and mortality were similar between the 2 groups (surgical mortality rate 7.8%). Follow-up ranged from 1.0 to 167.6 months (mean 13.0, median 5.7). The 1- and 2-year actuarial survival rates were 6.3% and 0% in the younger PCC group and 31.3% and 15.0% in the older PCC group, respectively. Prognosis was dismal for the younger patients with PCC (P = 0.0008), but they may benefit from hepatic resection.

CONCLUSIONS

Younger patients with PCC had a significantly worse survival rate than older patients with PCC. Hepatectomy is rational and may benefit younger patients with PCC.

Clinicopathologic review of 58 patients with biliary papillomatosis

BACKGROUND

Biliary papillomatosis (BP) is a rare disease that is characterized by multiple numerous papillary adenomas in the biliary tree. The clinical features and outcome, however, are not well known. The authors retrospectively analyzed their clinicopathologic features and long-term follow-up results.

METHODS

Between March 1995 and January 2003, 58 patients were diagnosed with BP by cholangioscopic and histologic findings at a tertiary referral center, Asan Medical Center (University of Ulsan College of Medicine, Seoul, Korea). The authors retrospectively reviewed the medical records to obtain demographic, radiologic, cholangioscopic, and pathologic data.

RESULTS

The common clinical manifestations at the presentation of patients were repeated episodes of abdominal pain, jaundice, and acute cholangitis. Acute cholangitis was more common in patients with mucin-hypersecreting BP (MBP), whereas patients with nonmucin-producing BP (NMBP) were more asymptomatic (P < 0.05). Papillary adenocarcinoma and mucinous carcinoma were detected in 48 patients (83%) with papillary adenomas. Overall survival rates of NMBP and MBP were 89% and 69% at 1 year, 57% and 37% at 3 years, and 52% and 19% at 5 years, respectively. The mean survival period of NMBP and MBP was 52.27 +/- 6.72 months and 30.84 +/- 8.36 months, respectively.

CONCLUSIONS

BP should be regarded as a premalignant disease with high malignant potential. The pathogenesis of progression from benign to malignant disease may follow the adenomacarcinoma sequence. Although clinical presentations were somewhat different for patients with NMBP and MBP, the long-term survival rate was similar.

Expression of matrix metalloproteinase-2 and -9 and tissue inhibitor of metalloproteinase-1 and -2 in intraductal and nonintraductal growth type of cholangiocarcinoma

BACKGROUND

The intraductal growth (IG) type of cholangiocarcinoma has a better prognosis than the mass forming (MF) and periductal infiltrating (PI) types. Matrix metalloproteinase (MMP)-2 and MMP-9, regulated by tissue inhibitor of metalloproteinases (TIMP)-2 and TIMP-1, respectively, play important roles in the degradation of the basement membrane during tumor invasion. Alteration in MMPs and TIMPs may regulate the gross morphology of cholangiocarcinoma.

METHODS

MMP-2 and MMP-9 were analyzed in 35 cholangiocarcinomas and 4 normal livers with fresh tissue using zymography and real-time reverse transcription-polymerase chain reaction (RT-PCR), and expressions of MMP-2, MMP-9, TIMP-1, and TIMP-2 were evaluated in 76 cholangiocarcinomas by immunohistochemistry.

RESULTS

Activity of MMP-2 and its active form were detected in 80% and 57% of cholangiocarcinomas respectively. The total MMP-2, active 62 kDa MMP-2, and MMP-2 mRNA increased 5.4 and 8.2 times, 4.4 and 10.9 times, and 2.9 and 5.8 times in the MF and PI types, respectively, compared to the IG type. The majority of MMP-9 was in the proform and active 82 kDa MMP-9 was detected in 9% of cholangiocarcinomas. MMP-9 revealed no significant difference in relation to the gross types. The balanced expressions of MMP-2/TIMP-2 and MMP-9/TIMP-1 were significantly decreased in the MF and PI types, compared to the IG type. In the normal and nonneoplastic livers, the expressions of MMP-2 and MMP-9 were very low without active forms.

CONCLUSIONS

The activities of MMP-2 and loss of balanced expressions of MMP-2/TIMP-2 and MMP-9/TIMP-1 are suggested as playing important roles in invasive growth related to the gross type of cholangiocarcinoma.

Increasing expression of gastrointestinal phenotypes and p53 along with histologic progression of intraductal papillary neoplasia of the liver

Intraductal papillary neoplasia of the liver (IPN-L) was recently proposed as the name for intraductal papillary proliferation of neoplastic biliary epithelium with a fine fibrovascular stalk resembling intraductal papillary mucinous neoplasm of the pancreas. We histochemically and immunohistochemically examined IPN-L alone or associated with hepatolithiasis, with an emphasis on the gastrointestinal metaplasia, nuclear p53 expression, and histologic progression. A total of 66 cases of IPN-L were divided into 4 groups: group 1, IPN-L with low-grade dysplasia (13 cases); group 2, IPN-L with high-grade dysplasia (20 cases); group 3, IPN-L lined with carcinoma in situ and no or microinvasion (19 cases); and group 4, group 3 with distinct invasive carcinoma (14 cases). It is suggested that IPN-L progresses from group 1 to group 4. As controls, 20 cases of nonneoplastic intrahepatic large bile ducts and 17 cases of nonpapillary invasive intrahepatic cholangiocarcinoma (ICC) were used. Biliary epithelial hypersecretion of sialomucin rather than sulfomucin was prevalent in IPN-L, and this was associated with the progression of INP-L. Immunohistochemically, cytokeratin (CK) 20 and MUC2, a gastrointestinal marker, were expressed more frequently in IPN-L than in nonneoplastic bile ducts and nonpapillary ICC (P <0.01), and their incidence were significantly increased in parallel with the progression of IPN-L (P < 0.01). In contrast, expression of CK 7, a biliary marker, was decreased in IPN-L compared with nonpapillary ICC. Nuclear p53 immunostaining was detected in 30% of IPN-L as a whole and increased in tandem with the progression of IPN-L (P < 0.01). It is suggested that IPN-L forms a spectrum of biliary epithelial neoplasia with frequent gastrointestinal metaplasia, different from the usual nonpapillary ICC, and shows stepwise progression from the perspective of mucin profile, gastrointestinal metaplasia, and p53 nuclear expression.