Small cell carcinoma of the gall-bladder with intestinal metaplastic epithelium

Large Cell Neuroendocrine Carcinoma of the Extrahepatic Bile Duct

Primary neuroendocrine tumors originating from the extrahepatic bile duct are rare. Among these tumors, large cell neuroendocrine carcinomas (NECs) are extremely rare. A 59-year-old man was admitted to Sanggye Paik Hospital with jaundice that started 10 days previously. He had a history of laparoscopic cholecystectomy, which he had undergone 12 years previously due to chronic calculous cholecystitis. Laboratory data showed abnormally elevated levels of total bilirubin 15.3 mg/dL (normal 0.2-1.2 mg/dL), AST 200 IU (normal 0-40 IU), ALT 390 IU (normal 0-40 IU), and gamma-glutamyl transferase 1,288 U/L (normal 0-60 U/L). Serum CEA was normal, but CA 19-9 was elevated 5,863 U/mL (normal 0-37 U/mL). Abdominal CT revealed a 4.5 cm sized mass involving the common bile duct and liver hilum and dilatation of both intrahepatic ducts. Percutaneous transhepatic drainage in the left hepatic duct was performed for preoperative biliary drainage. The patient underwent radical common bile duct and Roux-en-Y hepaticojejunostomy for histopathological diagnosis and surgical excision. On histopathological examination, the tumor exhibited large cell NEC (mitotic index >20/10 high-power field, Ki-67 index >20%, CD56 [+], synaptophysin [+], chromogranin [+]). Adjuvant concurrent chemotherapy and radiotherapy were started because the tumor had invaded the proximal resection margin. No recurrence was detected at 10 months by follow-up CT.

Extrahepatic biliary obstrution secondary to neuroendocrine tumor of the common hepatic duct

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Extra hepatic biliary obstruction can be frequently caused by tumors.

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Differentiation between cholangiocarcinoma and an unusual bile duct tumor such as a neuroendocrine tumor (NET) is very difficult preoperatively.

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Prognosis of NET of the extrahepatic bile duct is dependent on the grade of the tumor however is markedly better than cholangiocarcinoma.

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Unusual biliary tumors can not be diferentiated preoperatively from cholangiocarcinoma.

Introduction

Primary neuroendocrine tumors (NET) of the extrahepatic biliary tree are a rare entity with less than 100 reported cases in the literature.

Presentation of case

Here, we report a case of NET of the extrahepatic bile duct in a 64-year-old male patient presenting with painless jaundice, direct hyperbilirubinemia, and mildly elevated transaminases. Diagnostic workup with an ultrasound revealed dilation of the intrahepatic biliary ducts, without cholelithiasis or choledocholithiasis. Additional cross sectional imaging identified a stricture at the confluence of the common hepatic and cystic duct junction. Given lack of additional findings presumptive diagnosis of localized klatskin’s tumor was made. The patient subsequently underwent resection of the common bile duct and roux-en-y hepaticojejunostomy reconstruction. Final pathologic diagnosis showed G2 well-differentiated NET of the extrahepatic bile duct, measuring 1.3 × 1.1 × 1 cm.

Discussion

When a patient is evaluated for a primary bile duct neoplasm, differentiation between cholangiocarcinoma and an unusual bile duct tumor, such as a NET is very difficult before surgical resection and histologic review.

Conclusion

NET of the extrahepatic biliary tree are a rare entity. Typical presentation is with painless jaundice and other symptoms related to obstruction of the biliary tree and the diagnosis is usually made post-operatively.

A case of neuroendocrine carcinoma in the hepatic hilar lymph nodes concomitant with an adenocarcinoma of the gallbladder

BACKGROUND

Neuroendocrine tumors (NETs) are rare especially in the gallbladder. They have not been elucidated in the pathogenesis, clinicopathological characteristics, and treatment options.

CASE PRESENTATION

We present a 76-year-old woman with a gallbladder tumor and hepatic hilar lymph node swelling. The lymph node biopsy demonstrated neuroendocrine carcinoma (NEC). We performed cholecystectomy, hepatic hilar lymphadenectomy, extrahepatic biliary duct resection, and hepaticojejunostomy prior to chemotherapy. Pathological examination revealed the gallbladder mass was an adenocarcinoma invading to the muscular layer without any NEC components, whereas the hepatic hilar lymph nodes were filled with high-grade NEC cells with negligible area of adenocarcinoma. The patient received general chemotherapy consisting of carboplatin and etoposide, but a recurrence in the para-aortic lymph nodes occurred 4 months after surgery.

CONCLUSIONS

We report a rare case of NEC of the hepatic hilar lymph nodes that were concomitant with an adenocarcinoma of the gallbladder. High-grade NEC generally has an aggressive behavior and an optimal treatment strategy should be chosen for each patient.

Small Cell Carcinoma of the Gallbladder: Case Report and Comprehensive Analysis of Published Cases

Background. Gallbladder small cell carcinoma is a rare and highly aggressive malignancy with no established standard of care treatment. We described here a case report of small cell gallbladder cancer and we then performed a comprehensive review of 72 case reports of this disease. Methods. Published case reports of small cell carcinoma of the gallbladder between 1983 and 2014 were reviewed. Treatment modalities and survival were analyzed for metastatic and localized disease. Results. Median overall survival for all patients was 13 months. Metastatic disease was identified in 72% of cases. Treatment of metastatic disease with chemotherapy showed a significant survival benefit (p < 0.001) compared to no chemotherapy, and the use of platinum doublet with etoposide showed a nonsignificant 4-month improvement in survival compared to other chemotherapy regimens (p = 0.13). Adjuvant therapy did not demonstrate an improvement of median overall survival in local disease (p = 0.78). Conclusion. Given the limited available data, systemic therapy with platinum and etoposide should be considered for patients with metastatic small cell carcinoma of the gallbladder. Adjuvant chemoradiation or chemotherapy for treatment of local disease warrants further investigation.

Primary Mixed Adenoneuroendocrine Carcinoma of the Gallbladder in a 55-Year-Old Female Patient: A Case Report and Review of the Literature

Mixed adenoneuroendocrine carcinomas (MANECs) of the biliary tract are rare tumors, and to date only a few cases arising in the gallbladder have been reported. Their histogenesis is a matter of debate, since the biliary tract normally lacks neuroendocrine cells. However, the immunohistochemical identification of nonneoplastic neuroendocrine cells in both biliary adenocarcinomas and intestinal metaplasia has been documented. Here we report a case of a 55-year-old female patient presenting with right upper quadrant pain, cholelithiasis, and a gallbladder mass identified after cholecystectomy. The histopathologic examination showed a MANEC, composed of an intestinal-type adenocarcinoma and a large cell neuroendocrine carcinoma, arising in a background of enteric metaplasia with extensive high-grade dysplasia. Moreover, we report the presence of focal pancreatic intraepithelial neoplasia-like epithelial lesions, which has not been described for these tumors yet. The histopathologic features of this case provide further support for the theory that MANECs arise following a metaplasia-dysplasia-carcinoma pathway.

Concomitant small cell neuroendocrine carcinoma of gallbladder and breast cancer

The neuroendocrine carcinoma is defined as a high-grade malignant neuroendocrine neoplasm arising from enterochromaffin cells, usually disposed in the mucosa of gastric and respiratory tracts. The localization in the gallbladder is rare. Knowledge of these gallbladder tumors is limited and based on isolated case reports. We describe a case of an incidental finding of small cell neuroendocrine carcinoma of the gallbladder, observed after cholecystectomy for cholelithiasis, in a 55-year-old female, who already underwent quadrantectomy and sentinel lymph-node biopsy for breast cancer. The patient underwent radiotherapy for breast cancer and six cycles of chemotherapy with cisplatin and etoposide. Eighteen months after surgery, the patient was free from disease. Small cell neuroendocrine carcinoma of the gallbladder has poor prognosis. Because of the rarity of the reported cases, specific prognostic factors have not been identified. The coexistence of small cell neuroendocrine carcinoma of the gallbladder with another malignancy has been reported only once. The contemporary presence of the two neoplasms could reflect that bioactive agents secreted by carcinoid can promote phenotypic changes in susceptible cells and induce neoplastic transformation.

A case of mixed adenoneuroendocrine carcinoma of the gallbladder arising from an intracystic papillary neoplasm associated with pancreaticobiliary maljunction

A 54-year-old Japanese woman was referred with a gallbladder tumor. Based on the results of the computed tomography scan, endoscopic retrograde cholangiopancreatography, and magnetic resonance cholangiopancreatography, a mucin-producing neoplasm of the gallbladder associated with pancreaticobiliary maljunction was diagnosed. Extended cholecystectomy, extrahepatic bile duct resection, and choledochojejunostomy were performed, and she remains free of recurrence 24 months after resection. Histopathological examination revealed that the papillary component of the lesion was an intracystic papillary neoplasm with diverse characteristics of pancreaticobiliary epithelium and intestinal epithelium including mucin. In this component, most of the papillary lesion was a high-grade intraepithelial neoplasm, but also showed slight invasion into the muscular layer. The nodular component consisted of both poorly differentiated biliary type adenocarcinoma and large cell neuroendocrine carcinoma. We report a rare case of a mixed adenoneuroendocrine carcinoma arising from an intracystic papillary neoplasm associated with pancreaticobiliary maljunction. As for the histogenesis of this tumor, based on the histopathologic appearance, transdifferentiation from poorly differentiated biliary type adenocarcinoma to large cell neuroendocrine carcinoma is considered the most possible histogenesis of this tumor.

Distal humerus as delayed site of metastasis from small cell carcinoma of gallbladder

Background. Small cell carcinoma (SCC) of the gallbladder is a rare entity and is often seen in elderly women. SCC of gallbladder is typically a nonsecretory carcinoid tumor without overt clinical symptoms and is often discovered at advanced stages. SCC of gallbladder carries a dismal prognosis as compared to SCC of lung and adenocarcinoma of gallbladder. To date, only 73 case reports have been published in the world literature. Case Presentation. Herein, we report a case of a 73-year-old Saudi woman who presented with one week history of right upper quadrant abdominal pain and obstructive jaundice and was found to be a case of locally advanced, metastatic SCC of gallbladder cT4N1M1 (liver, para-aortic lymph nodes, and bone). The patient was treated with neoadjuvant etoposide and cisplatin (EP) chemotherapy three cycles after biliary stenting followed by radical cholecystectomy, lymphadenectomy, and adjuvant EP chemotherapy and then one year later developed distal humerus osseous metastasis. Conclusion. SCC of the gallbladder is very rare entity and is often seen at advanced stages. Osseous metastases of peripheral skeleton from SCC gallbladder are rarely reported. Surgery is curative option but only for early stage tumors. Incorporation of chemotherapy along with radical resection increases the survival.

Neuroendocrine carcinoma of the extrahepatic bile duct: Case report and literature review

Neuroendocrine carcinoma (NEC) of the extrahepatic bile duct is rare, and only 22 cases have been reported. Only two of these were large-cell NEC (LCNEC); the vast majority were small-cell NEC. Here, we report a third case of LCNEC of the extrahepatic bile duct. A 76-year-old male presented to a local hospital with painless jaundice. Imaging studies revealed a tumor at the hepatic hilum. The patient underwent right hepatic lobectomy, bile duct resection, and cholecystectomy. The resection specimen showed a 5.0-cm invasive neoplasm involving the hilar bile ducts and surrounding soft tissue. Histologically, the tumor consisted of nests of medium to large cells with little intervening stroma. The tumor invaded a large portal vein branch. All four excised lymph nodes were positive for metastasis, and metastatic deposits were also present in the gallbladder wall. The tumor was diffusely positive for synaptophysin and focally positive for chromogranin A. Approximately 70%-80% of the tumor cells were positive for Ki-67, indicating strong proliferative activity. A diagnosis of LCNEC was made. A few bile ducts within and adjacent to the invasive tumor showed dysplasia of the intestinal phenotype and were focally positive for synaptophysin and chromogranin A, suggesting that the dysplastic intestinal-type epithelium played a precursor role in this case. A postoperative computer tomography scan revealed rapid enlargement of the abdominal and retroperitoneal lymph nodes. The patient died 21 d after the operation. NEC of the bile duct is an aggressive neoplasm, and its biological characteristics remain to be better defined.

Primary small cell carcinoma of the lesser omentum

Although pulmonary small cell carcinoma (SCC) is seen frequently, SCC that originates from the extrapulmonary organs is extremely rare. We herein report a case of a SCC located in the lesser omentum. A 61-year-old male was admitted to our department due to intermittent epigastralgia for 2 months. Ultrasonography (US) revealed an irregular hypoechoic mass measuring about 58 mm × 50 mm × 45 mm under the left lobe of the liver. Magnetic resonance imaging (MRI) was performed to verify the irregular mass with T1- and T2- weighted images between the left lobe of liver and the stomach. At laparotomy, the well-circumscribed neoplasm was found in the lesser omentum, and the fundus of the neoplasm was located in the root of left gastric artery. Intraoperative microscopic evaluation of frozen sections revealed malignancy of the lesser omentum. Resection of the neoplasm was performed, and the combined resection of the vagal nerve was also performed for the partial adhesion. Pyloroplasty was performed for avoiding delayed gastric emptying caused by combined resection of vagal nerve. The lymph nodes dissection at lesser curvature and right cardia was also performed with a negative result. Based on the histological findings, the final diagnosis of primary lesser omental SCC was confirmed. The pathologic staging showed locoregional disease.

Neuroendocrine tumors of the gallbladder: an evaluation and reassessment of management strategy

BACKGROUND

Gallbladder neuroendocrine tumors (GB-NETs) represent only 0.5% of all NETs, and little is known about their biological behavior. We sought to provide an overview of the current state of knowledge about GB-NETs and provide a recommendation for management.

STUDY

A PubMed search was undertaken using the following criteria: primary gallbladder and carcinoid or NET. We also interrogated the SEER 9, 13 and 17 registries (1973 to 2005) and the Niigata registry (2003) to assess the epidemiology and clinicopathological characteristics. Finally, we compared the clinical presentation, management and prognosis of GB-NETs to that of gallbladder adenocarcinoma.

RESULTS

GB-NETs probably derive from either a multipotent stem cell or neuroendocrine cells in intestinal or gastric metaplasia of the gallbladder epithelium, which occurs consequent upon cholelithiasis/chronic inflammation. Clinically and at surgery, GB-NETs are indistinguishable from gallbladder cancer (GBC) and "carcinoid syndrome" is evident in only ∼1%.The median survival was only 9.8 months among 278 cases of GB-NETs reported in SEER. The 5 year survival rate for tumors classified as carcinoids/neuroendocrine carcinoma or small cell cancer (SCC) was 36.9 and 0%, respectively. Soga divided GB-NETs into typical and variant carcinoids with 5 year survival rates of 60.4% and 21.3% respectively.

CONCLUSIONS

GB-NETs have an aggressive behavior, and once diagnosed, extensive surgical management and careful NET follow up with CT scan is mandatory to facilitate early detection of recurrence. Since more aggressive surgical management for GBC has shown increased survival rates for these tumors, a similar strategy seems reasonable for GB-NETs. However, in high grade metastatic tumors, the primary management is mainly medical.

Two cases of small cell carcinoma of the gallbladder

Small cell carcinoma of the gallbladder is a rare disease process with approximately 40 cases reported in the literature. It is most often found in elderly female population and is associated with cholelithiasis and cigarette smoking. A multidisciplinary approach to treatment with wide surgical resection and adjuvant chemotherapy is the current standard of care. Notwithstanding prompt medical intervention, it is a disease with a poor prognosis. The pathology is characterized by early metastases and extensive local invasion. Herein, we report two cases of small cell carcinoma addressed at our institution. In both cases, a radical resection was performed with subsequent referral to oncology for additional therapy.

Small cell carcinoma of the gall bladder: role of adjuvant chemotherapy

INTRODUCTION

Small cell cancer of the gallbladder is a rare malignancy with a poor prognosis. There is limited information in the literature on the best therapeutic approach towards this cancer with anecdotal therapy extrapolated from experience in small cell cancer of the lung.

CASE REPORT

We are presenting a 70-year-old woman with this cancer who is undergoing multimodality treatment, along with a review of literature on previously reported cases.

Incidental gallbladder visualization on nonhepatobiliary nuclear medicine studies: case series and review of the literature

Gallbladder uptake is occasionally encountered with commonly used nonhepatobiliary radiopharmaceuticals. Identification of the biliary tract by a nonhepatobiliary agent can identify disease, such as uptake of labeled white blood cells. However, in most cases, gallbladder uptake of nonhepatobiliary tracers is not due to pathology in these cases. It is important to avoid attributing gallbladder uptake to disease in the gallbladder or adjacent anatomic structures. We present 3 cases of unexpected gallbladder tracer uptake and provide a review of the literature describing incidental gallbladder uptake on nonhepatobiliary nuclear medicine studies. The potential for misdiagnosis and the steps taken to avoid this are discussed.

MDCT findings in neuroendocrine carcinoma of the gallbladder: case report

Neuroendocrine tumors are commonly seen in the gastrointestinal tract, but they are extremely rare in the gallbladder. In this study, sonographic and multidetector-row computed tomographic findings of a patient with neuroendocrine tumors of the gallbladder are presented.

Primary colorectal small cell carcinoma: a clinicopathological and immunohistochemical study of 10 cases

Colorectal small cell carcinoma (SmCC) is a rare tumor with an aggressive course. The aim of this study is to summarize our experience with this tumor and to highlight its immunohistochemical profile. Ten cases of colorectal SmCC were identified in our files and a panel of immunostains was performed. Follow up was available for the average of 3 years, during which 7 patients died and 3 were alive with disease. All cases were positive for LMWK, CK 19 and pancytokeratin but were negative for TTF-1 and CA 125. EGFR was positive in 7 cases. TTF-1 negative staining may be valuable in differentiating it from its pulmonary counterpart. CDX2, mCEA, CD56, synaptophysin, NSE and chromogranin can help differentiate it from non-endocrine poorly differentiated adenocarcinoma. The expression of EGFR in a subset of patients has not been reported earlier and has to be evaluated in larger series to assess its role in the planning of targeted biologic therapy.

Visualization of gallbladder with In-111 labeled octreotide in post prandial state

Somatostatin receptor scintigraphy is widely used in the management of neuroendocrine tumors. Somatostatin receptors are present in both neoplastic and normal tissues, which may lead to misinterpretation of the scans. Here, a patient with lung carcinoid imaged with In-111 octreotide is presented. Imaging was performed 4 and 24 hours after an intravenous injection of 185 MBq In-111 octreotide in the post prandial state. Whole body and SPECT images showed accumulation of radioactivity in the gallbladder. Imaging was repeated after fatty meal ingestion to differentiate abnormal activity and physiological uptake in the gallbladder. The abdominal SPECT studies at 28 hours revealed no uptake in the gallbladder, and the scintigraphic study was reported as normal so further excessive diagnostic procedures were prevented. Gallbladder can be visualized on somatostatin receptor scintigraphy even in the post prandial state. Delayed images after fatty meal administration are important for differential diagnosis.

Primary small cell carcinoma of the cecum

Cecal extrapulmonary small cell carcinoma (cESC) is extremely rare, with only single previous report of occurrence in a child. We report a 76-year-old man admitted for evaluation of a cecal mass seen in colonoscopy. Histology revealed small cell carcinoma with classic immunohistochemical profile similar to those seen in the colon. Further clinical survey documented absence of any other masses or abnormality. To the best of our knowledge, this is the first case of primary cESC occurring in an adult. Awareness of the pathologist and clinician of the cecum as a potential site of cESC may help to prevent misdiagnosis as poorly differentiated adenocarcinoma. This is crucial because extrapulmonary small cell carcinomas usually have worse prognosis.

Combined small cell carcinoma and clear cell carcinoma of the gallbladder: report of a case and review of the literature

We report a case of an incidental combined carcinoma of the gallbladder in a 66-year-old woman who underwent cholecistectomy for gallstones. The neoplasm was mainly constituted by a clear cell component and a small cell, chromogranin-positive one; it also showed some areas of conventional adenocarcinoma and foci of vascular invasion. The patient died after 3 years following treatment with combination chemotherapy. The histologic and immunohistochemical profile of the lesion is described, together with a brief review of the pertinent bibliography.

Small-cell undifferentiated carcinoma of neuroendocrine type originating in the gallbladder

PURPOSE

We report a case of small-cell undifferentiated carcinoma with neuroendocrine (SCUCN) of the gallbladder in a 67-year-old man who presented with suspected cholelithiasis. Treatment included a cholecystectomy and a 4-cycle course of etoposide and carboplatin.

CONCLUSIONS

Small-cell undifferentiated carcinoma with neuroendocrine features of the gallbladder is a rare disease with approximately 30 cases reported in the literature. Clinical characteristics include an association with cholelithiasis, an elderly age distribution, a female preponderance, and a correlation with cigarette smoking. It is known to behave aggressively and carry a grave prognosis, with extensive local invasion and early metastasis being characteristic. Medical and surgical therapies exist and have demonstrated best results when used in combination.

Small cell carcinoma of the gallbladder: a clinicopathologic, immunohistochemical, and molecular pathology study of 12 cases

Small cell carcinomas of the gallbladder are unusual neoplasms that have been characterized only recently. The authors describe the clinical, histopathologic, immunohistochemical, and molecular features of 12 small cell carcinomas of the gallbladder. The mean age at diagnosis was 69 years, and the male-to-female ratio was 5:7. The neoplasms had an average size of 3 cm, and 90% showed invasion of the muscularis propria and perimuscular connective tissue. Seventy-five percent of the carcinomas had metastasized or extended locally beyond the gallbladder at surgery. Survival was uniformly poor, with a mean survival of 10.7 months (range, 3-25 months). Half the small cell carcinomas were combined with other neoplasms. Four had foci of adenocarcinoma, one contained areas of squamous differentiation, and another had a component of carcinosarcoma. Immunohistochemical analysis showed focal reactivity for chromogranin (six of six cases), neuron-specific enolase (six of six cases), and Leu-7 (three of three cases). The molecular changes in small cell carcinomas were similar to those of adenocarcinomas occurring at this site, with a high frequency of p53 (75%) and p16INK4a (33%) abnormalities, and a low frequency of deleted in pancreatic carcinoma-4 inactivation (0%) and K-ras codon 12 mutations (17%). In contrast to pulmonary small cell carcinomas, p16INK4a function appears to be abrogated more frequently in these carcinomas.

Large cell neuroendocrine carcinoma of the gallbladder: report of two cases

We report two cases of primary large cell neuroendocrine carcinoma (LCNEC) of the gallbladder, which, to the best of our knowledge, represent the first description of this entity. One of the tumors consisted entirely of LCNEC, whereas the second tumor was composed of LCNEC and the more common intestinal-type adenocarcinoma. Both tumors were morphologically similar to their pulmonary counterpart and were characterized by large cells with prominent nucleoli, coarse chromatin, and a high mitotic rate. The cells showed an organoid growth pattern with rosette formation and frequent areas of necrosis. Panendocrine markers were expressed in a variable proportion of tumor cells in both cases, and one of the cases also showed focal positivity for type 2 somatostatin receptors. One of the tumors followed a rapidly fatal course despite aggressive surgical treatment and chemotherapy administration, and the second patient is still alive and disease-free 12 months after surgery. The description of these two cases of LCNEC of the gallbladder is significant for two reasons. From an academic standpoint, we now know that all the neuroendocrine tumors described in other organs can arise de novo in the gallbladder. More importantly, however, the recognition of this rare tumor type carries important clinical implications in regard to the use of chemotherapeutic agents and supplemental treatments (for example, somatostatin analogs).

Expression of an intestine-specific transcription factor (CDX1) in intestinal metaplasia and in subsequently developed intestinal type of cholangiocarcinoma in rat liver

CDX1 is a caudal-type homeobox intestine-specific transcription factor that has been shown to be selectively expressed in epithelial cells in intestinal metaplasia of the human stomach and esophagus and variably expressed in human gastric and esophageal adenocarcinomas (Silberg DG, Furth EE, Taylor JK, Schuck T, Chiou T, Traber PG: Gastroenterology 1997, 113: 478-486). Through the use of immunohistochemistry and Western blotting, we investigated whether CDX1 is also uniquely associated with the intestinal metaplasia associated with putative precancerous cholangiofibrosis induced in rat liver during furan cholangiocarcinogenesis, as well as expressed in neoplastic glands in a subsequently developed intestinal type of cholangiocarcinoma. In normal, control adult rat small intestine, specific nuclear immunoreactivity for CDX1 was most prominent in enterocytes lining the crypts. In comparison, epithelium from intestinal metaplastic glands within furan-induced hepatic cholangiofibrosis and neoplastic epithelium from later developed primary intestinal-type cholangiocarcinoma each demonstrated strong nuclear immunoreactivity for CDX1. CDX1-positive cells were detected in hepatic cholangiofibrotic tissue as early as 3 weeks after the start of chronic furan treatment. We further determined that the percentages of CDX1-positive neoplastic glands and glandular nuclei are significantly higher in primary tumors than in a derived, transplantable cholangiocarcinoma serially-propagated in vivo. Western blotting confirmed our immunohistochemical results, and no CDX1 immunoreactivity was detected in normal adult rat liver or in hyperplastic biliary epithelial cells. These findings indicate that CDX1 is specifically associated with early intestinal metaplasia and a later developed intestinal-type of cholangiocarcinoma induced in the liver of furan-treated rats.