A neoplasm with pancreatic and hepatocellular differentiation presenting with subcutaneous fat necrosis

Case report and literature analysis: pancreatic hepatoid carcinoma with multiple lymph node metastases progressing to liver metastasis after pancreaticoduodenectomy

Hepatoid carcinoma is an extrahepatic primary tumor displaying characteristics reminiscent of hepatocellular carcinoma differentiation, which is found in various organs, such as the stomach, ovaries, gallbladder, and pancreas. Reports of pancreatic hepatoid carcinoma remain scarce. Consequently, understanding of this disease remains a priority, with no established consensus on its diagnosis and management. Here, we reported the case of a 45-year-old woman diagnosed with hepatoid carcinoma located in the pancreatic head, accompanied by multiple lymph node metastases. Following pancreaticoduodenectomy, the patient developed liver metastases within 3 months. Subsequently, she underwent adjuvant therapy consisting of Teysuno and Durvalumab following microwave ablation for the liver metastases. Remarkably, the patient has survived for one year without significant disease progression. This case underscores the potential efficacy of immunotherapy as a promising treatment option for pancreatic hepatoid carcinoma. Further research and clinical trials are warranted to explore the optimal management strategies for this rare and challenging malignancy.

Mixed pancreatic hepatoid carcinoma: A surgical case report and literature review

BACKGROUND

Hepatoid carcinoma (HC) is a rare type of malignant tumor that shared similar features of morphology and immunohistochemistry with hepatocellular carcinoma (HCC). Pancreatic HC exists as either pure or mixed type. Mixed pancreatic HC is extremely rare, with only a few cases reported in the literature to date. Because of the rarity of mixed pancreatic HC, its clinical features including incidence, characteristics, and prognosis remain unclear. We herein report a case of a 49-year-old man who was diagnosed with mixed pancreatic HC with neuroendocrine differentiation and was treated with pancreaticoduodenectomy and adjuvant chemotherapy. We also review the existing case reports in literature.

PRESENTATION

A 49-year-old man was admitted to our hospital after a chronic abdominal pain in the upper right quadrant. Abdominal ultrasound revealed only one low-density retroperitoneal mass measured at 20 × 48mm in size in the pancreatic-duodenal junction, whereas contrast-enhanced computed tomography (CT) revealed three lymphatic neoplasms measured at 28 × 22 × 30 mm, 27 × 33 × 38 mm and 22 × 35 × 48 mm in size in the retroperitoneal pancreatic-duodenal junction. Ultrasound-guided tumor biopsy was performed. Pathological reading of tumor biopsy suspected of Paraganglioma/pheochromocytoma. Laparotomic retroperitoneal tumoral resection and lymphadenectomy was then performed. Histological reading was lymphatic metastasis of primary pancreatic hepatocellular carcinoma with neuroendocrine differentiation, which were immunohistochemically positive for CKAE1/AE3, Hepatocyte paraffin 1, Chromogranin. After three weeks of the first surgery, the patient was assigned with Positron Emission Tomography - Computed Tomography (PET-CT) before adjuvant chemotherapy, revealing a low-density high-metabolism mass, 26 × 28 mm in size within the parenchyma of pancreatic head. Laparotomic pancreaticoduodenectomy and standard lymphadenectomy was performed to resect one mass, which revealed the same immunohistology features with the first mass. The patient was followed up with FOLFIRINOX protocol, and after 12 cycles, there was no evidence of postoperative recurrence.

DISCUSSION

There are few reported cases describing pancreatic hepatoid carcinoma, especially mixed form with other histological associated component. Neuroendocrine differentiation is the majority associated component with 62.5% of all cases of mixed - type form.

CONCLUSION

Primary pancreatic hepatocellular carcinoma with neuroendocrine differentiation was rare, biopsy and immunohistochemistry appeared with high diagnostic value in this case. The prognosis of pancreatic HC depends on the extent and tumor eradication, and in this case we recorded no postoperative complications and no recurrence in the 6-month follow-up period.

Hepatoid carcinoma of the pancreas: A case report and review of the literature

BACKGROUND

Hepatoid carcinoma (HC) is an extremely rare neoplasm that is morphologically similar to hepatocellular carcinoma. HC has been described in various organs; however, HC of the pancreas is extremely rare. To our knowledge, only 38 cases have been reported. We present a case of HC of the pancreas in a 36-year-old male patient.

CASE SUMMARY

A 36-year-old cachexic man with no significant past medical history was transferred to our hospital with a history of painless jaundice, elevated blood glucose and significant weight loss. Lab tests showed elevated serum transaminases, bilirubin and alpha-fetoprotein levels. Magnetic resonance imaging of the upper abdomen showed a diffusely enlarged pancreas, appearing “sausage-shaped”. Magnetic resonance cholangiopancreatography showed upstream ductal dilation secondary to stricture of the main pancreatic duct and the common bile duct, which were not visible. Immunohistochemistry of biopsied tissue from a percutaneous pancreatic biopsy showed tumor cell positivity for HepPar1, polyclonal carcinoembryonic antigen and CK19, suggestive of HC of the pancreas. The characteristics of 39 patients with HC of the pancreas were reviewed.

CONCLUSION

HC of the pancreas is more prevalent in males, and patients have a median age of 57 years. It is most commonly asymptomatic or presents as abdominal back pain, and the pancreatic tail is the most common location. At the time of diagnosis, liver metastasis is often present.

Primary Hepatoid Carcinoma of the Pancreas: A Clinicopathological Study of 3 Cases With Review of Additional 31 Cases in the Literature

Primary pancreatic hepatoid carcinoma (PHC) is very rare. Here, we reported 3 such cases with review of additional 31 cases in the literature. Our 3 patients were male (83, 72, and 54 years old, respectively). Serum α-fetoprotein (AFP) was elevated in 1 patient (case 3, 8338 ng/mL) and not measured in the other two. The PHC in patient 1 (pathological stage pT2N0M0) and patient 2 (pT3N0M0) showed pure hepatocellular carcinoma (HCC)-like morphology, whereas in case 3 it was a PHC with true glandular differentiation (pT4N0M0). The diagnosis of PHC was confirmed with positive immunohistochemical staining in the tumor cells for AFP (2/3), Hep Par 1 (3/3), glypican-3 (2/3), arginase-1 (2/3), and Sal-like protein 4 (1/3). CD10 and polyclonal carcinoembryonic antigen stains show focal canalicular pattern in 2/3 tumors. Patient 1 did not receive further treatment after resection and was alive with no evidence of disease at 107 months. Patient 2 died of postoperative complications, whereas patient 3 received postsurgical chemoradiation and died of disease at 29 months. Our findings and literature review indicate that PHCs can be divided into 4 histological subtypes: with pure HCC-like morphology (n = 22), with neuroendocrine differentiation (n = 8), with true glandular differentiation (n = 3), and with acinar cell differentiation (n = 1). On univariate analysis, pure HCC-like morphology was associated with better disease-specific survival (DSS; P = .04), whereas lymph node and distant metastases were associated with worse DSS ( P = .002 for both). Age, gender, presenting symptoms, serum AFP level, and T stage were not associated with DSS. On multivariate analysis, none of these parameters was significantly associated with DSS.

Pancreatic Hepatoid Carcinoma Mimicking a Solid Pseudopapillary Neoplasm: A Challenging Case on Endoscopic Ultrasound-guided Fine-needle Aspiration

A 59-year-old man was admitted to our hospital for treatment of a 45 mm pancreatic mass found during a medical examination. Endoscopic ultrasound-guided fine-needle aspiration cytology showed polygonal cells with pseudopapillary structures. The tumor cells were positive for nuclear/cytoplasmic β-catenin and CD10, and negative for chromogranin A. After a tentative diagnosis of a solid pseudopapillary neoplasm, middle pancreatectomy was performed. Histologically, polygonal cells with abundant eosinophilic cytoplasm formed in the trabeculae and were immunohistochemically positive for HepPar1 and protein induced by vitamin K absence or antagonist-II. The tumor was finally diagnosed to be pancreatic hepatoid carcinoma. No recurrence occurred for 12 months, even without adjuvant chemotherapy.

Hepatoid carcinoma of the pancreas combined with serous cystadenoma: a case report and review of the literature

Pancreatic hepatoid carcinoma (HC) is an extremely uncommon neoplasm of pancreas that resembles hepatocellular carcinoma (HCC). We report a case of incidentally detected pancreatic HC combined with a serous microcystic cystadenoma, in a 47-year-old man, while he was being evaluated for renal calculi. Contrast enhanced computed tomography (CECT) of abdomen revealed a lesion with mild heterogeneous enhancement in the tail of pancreas and another proximal lesion having moderate enhancement, and a calculus in the neck of gallbladder. Serum chromogranin, carcinoembryonic antigen (CEA) and CA 19-9 levels were within normal limits. He underwent laparoscopic distal pancreatectomy with splenectomy and cholecystectomy. Pathologically the distal tumor was encapsulated and characterized by eosinophilic cytoplasm, vesicular nucleus with prominent nucleolus and intranuclear eosinophilic inclusions. The cells were arranged in trabecular pattern separated by sinusoids. Canalicular and intercellular bile plugs were seen. On immunohistochemistry tumor cells were positive for hepatocyte specific antigen and weakly positive for alpha fetoprotein (AFP). The proximal tumor showed features of serous microcystic adenoma. Based on these findings, the case was diagnosed as hepatoid tumor of pancreas combined with serous microcystic cystadenoma. Post operative AFP was 1.75 IU/mL. The patient is on follow up for the last eight months and there is no evidence of recurrence.

Hepatoid Carcinoma of the Pancreas: A Case Report and Review of the Literature

Background: Hepatoid carcinoma (HC) is a rare extrahepatic malignancy that shares many morphological and serological features with hepatocellular carcinoma. HC has been reported to arise from several organs that are derived from the foregut endoderm, including the stomach, gallbladder, and pancreas. We present a case of an elderly man with hepatoid adenocarcinoma of the pancreatic head with duodenal invasion, presenting with pancreatitis and a gastrointestinal bleed. With only 23 reported cases at the time of our literature search, we discuss the presentation, histopathology, and management of such a rare disease.

Case presentation: A 71-year-old man presented initially with abdominal pain and was treated conservatively for pancreatitis. Four months later, he presented with melena and anemia. His examination was noncontributory. Esophagogastroduodenoscopy revealed a friable ampulla of Vater, and a CT scan of the abdomen showed a 4.5 cm pancreatic head mass. Fine needle aspirate revealed an epithelioid neoplasm with hepatoid morphology. Serum α-fetoprotein was normal. Surgical resection confirmed hepatoid adenocarcinoma of the pancreas with positive lymphadenopathy and negative margins. There was no radiographical or gross evidence of distant spread. Observation and adjuvant gemcitabine were discussed as possible options. The patient elected to receive care closer to home and will continue surveillance imaging.

Conclusion: With only 23 reported cases, pancreatic HC represents a rare entity within gastrointestinal oncology. There is no clear postoperative adjuvant standard therapy for this likely heterogeneous group of tumors. Although surgical resection is the mainstay of upfront treatment, metastatic disease to the lymph nodes or liver portends a poor prognosis and may warrant treatment such as transarterial embolization, chemotherapy, or radiotherapy.

Hepatoid carcinoma of the pancreas with lymphoid stroma: first description of the clinical, morphological, immunohistochemical, and molecular characteristics of an unusual pancreatic carcinoma

We report a case of tumour in the head of the pancreas observed in a 57-year-old man with a history of worsening jaundice and elevated alpha-fetoprotein (AFP) serum level, who underwent Whipple pancreatoduodenectomy. Histologically, the tumour was predominantly composed of solid sheets of large eosinophilic cells with a prominent lymphoid infiltration without association neither with DNA microsatellite instability nor Epstein-Barr virus infection. The tumour was diffusely and strongly positive for hepatocyte paraffin-1 (Hep Par-1) and glypican-3 leading to the diagnosis of hepatoid carcinoma. Strong cytoplasmic staining for AFP was focally observed. Moreover, tumour cells showed countless cytoplasmic eosinophilic globules immunoreactive for the stress protein p62. A primary hepatocellular carcinoma of the liver was ruled out by careful clinical analysis. Hepatoid carcinoma is an extremely rare pancreatic neoplasm, and here, we describe the first case of such variant associated with lymphoid stroma. The characteristic histologic features and the immunophenotypic profile help in distinguishing this carcinoma from other pancreatic tumours, notably from medullary carcinoma.

Pancreatic hepatoid carcinoma: a rare form of pancreatic neoplasm

Primary pancreatic hepatoid carcinoma (PHC) is extremely rare, resembling hepatocellular carcinoma (HCC) in terms of morphology and immunohistochemical features. Hepatoid carcinoma can present in other organs, most noticeably in the stomach. PHC is present in two forms either a pure form like HCC or admixed with other histologic tumor components characteristic of the underlying primary site (endocrine tumors, ductal, or acinar adenocarcinomas). Here, we report a 69-year-old male patient with distal pancreatic mass incidentally found during a CT scan workup for a pulmonary nodule suspicious for metastatic prostate adenocarcinoma. We described the clinical, cytological, and histological finding and conducted a literature review.

Primary hepatocellular carcinoma ("hepatoid" carcinoma) of the pancreas: a case report and review of the literature

Key Clinical Message

We present a case of hepatocellular carcinoma located within the pancreas. These tumors occur in the body and tail of the pancreas, with a male predominance, and at a younger age. Tumors with pure hepatocellular histopathology have better survival and recurrence rates and should be offered surgical therapy if possible.

A rare case of metastatic pancreatic hepatoid carcinoma treated with sorafenib

BACKGROUND

Hepatoid carcinoma (HC) is a rare histopathological tumor type with prominent features of hepatoid differentiation, and while most of the reported cases are of gastric origin, ten cases of pancreatic HC have been reported to date. The majority of HC cases are metastatic at presentation, mainly to the liver, lymph nodes, and lungs. They are aggressive, invading, and proliferating in the venous and lymphatic systems, with a behavior similar to that of hepatocellular carcinoma. Diagnosis is challenging: alpha-Fetoprotein, the most useful marker, is not always positive.

METHODS

We present the first case of metastatic pancreatic HC treated with sorafenib, an oral multikinase inhibitor approved for advanced hepatocellular carcinoma that has antiangiogenic, pro-apoptotic, and raf-kinase inhibitory properties.

RESULTS

The patient, a 37-year-old male, was diagnosed with hepatoid carcinoma of the pancreas that had metastasized to liver, lungs, and lymph nodes. The cytokeratin (CK) profile was useful for the diagnosis: Both the hepatoid and adenocarcinoma components of the tumors were CK18+, CK19+, and CK20+/-, whereas normal and neoplastic hepatocytes are CK18+, CK19-, and CK20-. Amylase, lipase, and liver enzyme levels were elevated, but bilirubin was normal. Treatment with sorafenib resulted in more than 7 months of progression-free survival. Therapy was discontinued after 8 months when his bilirubin level increased dramatically. Signs of liver failure resolved temporarily with insertion of a biliary stent, but his condition deteriorated and he died 3 months later, 1 year after diagnosis.

CONCLUSION

In the absence of evidence-based experience with this rare and aggressive tumor and given its similarities with hepatocellular carcinoma, sorafenib should be considered as a possible treatment.

Hepatoid carcinoma of the pancreas penetrating into the gastric cavity: a case report and literature review

A 79-year-old Japanese woman was admitted to our hospital for treatment of a pancreatic tumor measuring approximately 7 × 5 cm. The tumor had invaded the left adrenal gland and gastric wall and had penetrated into the gastric cavity. Surgical resection was performed. The tumor was composed of a brown to whitish solid area and a zone of hemorrhage, necrosis, and cystic degeneration resembling the gross features of solid pseudopapillary tumor (SPT). Histologically, the tumor showed a heterogeneous growth pattern with a combination of seat-like, trabecular, papillary and hemorrhagic-necrotic areas in various proportions. The differential diagnoses first considered were acinar cell carcinoma, neuroendocrine carcinoma and SPT with malignant transformation. Immunohistochemistry showed tumor cells were negative for pancreatic exocrine enzymes and endocrine markers. Tumor cells diffusely expressed cytokeratin 19, alpha-fetoprotein, carcinoembryonic antigen and glypican-3, but lacked vimentin or β-catenin expression. Small proportions of tumor cells expressed hepatocyte paraffin-1. Although typical morphological features of well-differentiated hepatocellular carcinoma (HCC) were not distinctly apparent, the tumor morphology partly resembled poorly differentiated HCC. Given these findings and considerations, the tumor was finally diagnosed as poorly differentiated hepatoid carcinoma of the pancreas.

Ductal Adenocarcinoma of the Pancreas

Pancreatic ductal adenocarcinoma (PDAC) and its variants comprise between 80% and 90% of all tumors of the exocrine pancreas. Because of its silent course, late clinical manifestation, and rapid growth, it is considered a silent killer. Only 10% to 15% of cases are resectable and the 5-year survival rate remains lower than 5%. The differential diagnosis between PDAC and chronic pancreatitis is a challenge for pathologists. This article provides a guide for pathologic evaluation of PDAC specimens with the macroscopic and microscopic features of common PDAC and its variants and discusses the differential diagnosis and morphologic and immunophenotypical prognostic parameters.

Hepatoid carcinoma of the pancreas combined with neuroendocrine carcinoma

Hepatoid carcinoma is a primary extrahepatic carcinoma whose morphology, immunohistochemistry, and behavior are similar to those of hepatocellular carcinoma. The most common sites of extrahepatic carcinoma are the stomach and ovary, but nine cases of hepatocellular differentiation of the pancreas have been reported in the literature. We report another case of hepatoid carcinoma of the pancreas that was associated with the development of a pancreatic endocrine carcinoma in a 46-year-old man. Serum alpha-fetoprotein (AFP) was elevated to 262.49 IU/mL and radiological examinations revealed a mass measuring 7.5 cm in diameter in the head of the pancreas. He underwent a conventional Whipple operation, and light microscopy showed adenocarcinoma that was immunopositive for AFP, hepatocyte antigen, cytokeratin, chromogranin, synaptophysin, and alpha-1 antichymotrypsin. Although hepatoid differentiation was not shown unequivocally histologically, other immunohistochemistry findings supported the diagnosis of hepatoid carcinoma combined with neuroendocrine carcinoma. The patient was healthy and had no evidence of recurrence at 4 months after the surgery. This report describes why hepatoid carcinoma should be considered as a differential diagnosis of a pancreatic mass, especially when serum AFP is elevated.

Stem cells and liver regeneration

One of the defining features of the liver is the capacity to maintain a constant size despite injury. Although the precise molecular signals involved in the maintenance of liver size are not completely known, it is clear that the liver delicately balances regeneration with overgrowth. Mammals, for example, can survive surgical removal of up to 75% of the total liver mass. Within 1 week after liver resection, the total number of liver cells is restored. Moreover, liver overgrowth can be induced by a variety of signals, including hepatocyte growth factor or peroxisome proliferators; the liver quickly returns to its normal size when the proliferative signal is removed. The extent to which liver stem cells mediate liver regeneration has been hotly debated. One of the primary reasons for this controversy is the use of multiple definitions for the hepatic stem cell. Definitions for the liver stem cell include the following: (1) cells responsible for normal tissue turnover, (2) cells that give rise to regeneration after partial hepatectomy, (3) cells responsible for progenitor-dependent regeneration, (4) cells that produce hepatocyte and bile duct epithelial phenotypes in vitro, and (5) transplantable liver-repopulating cells. This review will consider liver stem cells in the context of each definition.

Hepatoid carcinoma of the skin: spontaneous rat skin hepatoid carcinoma with eosinophilic globules and crystals immunoreactive to alpha-1-antitrypsin

We present a case of hepatoid carcinoma of the abdominal skin in a male Wistar rat. Histopathologically, this carcinoma resembled human hepatocellular carcinoma with respect to trabecular-sinusoidal structures. Carcinoma tissues contain numerous eosinophilic globules and crystals, and in this case, we found the characteristic eosinophilic globules in the hepatoid carcinoma cells and the crystals in the extracellular portions. Vivid carcinoma cells full of eosinophilic globules were present near the necrotic areas in tumor tissue, wherein quadrate crystals unstained with eosin were observed. PAS staining after diastase digestion revealed that the globules were PAS positive and diastase resistant. In addition, we found that the hepatoid carcinoma cells were immunoreactive for alpha-1-antitrypsin (anti-A1AT) antibody with the globules and crystals staining peripherally, and a central unstained region. Ultrastructural study of intracytoplasmic globules and extracellular crystals revealed that the fringe of each globule and crystal had no limiting membrane and showed the same level of electron density. These findings suggest that the characteristic crystals in this tumor may have originated from the globules that were emitted from the carcinoma cells after their death as a result of saturation with intracytoplasmic globules.

Subcutaneous fat necrosis as the presenting feature of a pancreatic carcinoma: the challenge of differentiating endocrine and acinar pancreatic neoplasms

The association between pancreatic panniculitis and pancreatic disease is well described, but differentiation among the neoplastic causes of the syndrome remains difficult due to substantial overlap in histological and immunohistochemical features. We report a case of subcutaneous fat necrosis as the presenting feature in a 61-year-old man with metastatic carcinoma of pancreatic origin. Previous pathological evaluation of the patient's liver biopsy led to an initial diagnosis of adenocarcinoma of unknown primary site. One month later, the patient presented with pancreatic panniculitis, prompting further investigation. Immunohistochemistry was consistent with neuroendocrine differentiation, but the patient rapidly decompensated and died before the evaluation was complete, leaving the definitive diagnosis in question. In our review of the published reports of tumor types associated with pancreatic panniculitis, we found that immunohistochemical staining and electron microscopy can and should be used in conjunction with clinical correlation to accurately differentiate neuroendocrine tumors from carcinomas with acinar cell features. Accurate diagnosis of these tumors is necessary to determine prognosis and define appropriate therapy.

Pancreatic adenocarcinoma: update on the surgical pathology of carcinomas of ductal origin and PanINs

Pancreatic cancer is the fourth leading cause of cancer death in the US. Most pancreatic cancers are infiltrating ductal adenocarcinomas. The careful application of well-defined morphologic criteria can be used to differentiate between infiltrating ductal adenocarcinoma and reactive glands. While most pancreatic cancers are ductal adenocarcinomas, a number of histologically defined variants have been described. These are important to recognize because they have distinct clinical pathologic features. Pancreatic intraepithelial neoplasia (PanIN) is the presumed precursor lesion to infiltrating ductal adenocarcinoma, and PanIN lesions can mimic infiltrating cancer.

Adult stem cells in progression and therapy of hepatocellular carcinoma

Hepatocellular carcinoma is one of the most aggressive solid tumours associated with poor prognosis. Despite its significance, there is only an elemental understanding of the mechanisms that drive disease pathogenesis, and there are just limited therapy options. The medical community is currently experiencing a wave of enthusiasm for clinical trials, in which adult stem/progenitor cells are used for liver regeneration. This is based on promising results in animal models and encouraging reports from some initial clinical studies. On the other hand, several essential precautions are not being fully addressed. Stem cells may contribute to fibrosis or give rise to hepatic cancer stem cells as a source of hepatocellular carcinoma. This review outlines the current state of knowledge in progression of liver disease and highlights the function of adult stem cells in disease and therapy.

Hepatoid carcinoma of the pancreas producing protein induced by vitamin K absence or antagonist II (PIVKA-II) and alpha-fetoprotein (AFP)

We describe a rare case of hepatoid carcinoma of the pancreas with production of protein induced by vitamin K absence or antagonist II (PIVKA-II) and alpha-fetoprotein (AFP). The patient was a 49-year-old woman admitted because of high serum levels of PIVKA-II (1.63 AU/ml) and AFP (623 ng/ml) and abnormal ultrasonographic findings of the pancreas, found incidentally at medical checkup. Both ultrasonography and computed tomography showed swelling of the pancreas with small areas of low density, but no hepatic lesions. The serum levels of carcinoembryonic antigen and carbohydrate antigen 19-9 were not increased. A PIVKA-II and AFP-producing pancreatic cancer was strongly suspected, and total pancreatectomy was performed. Pathological examination showed that the tumor cells were arranged in trabecular and solid patterns with bile production, and were immunohistochemically positive for PIVKA-II and AFP, resembling hepatocellular carcinoma cells. The tumor was diagnosed as hepatoid carcinoma of the pancreas, and the patient has survived 48 months after initial diagnosis. It is important that hepatoid carcinoma be considered as a possible malignant tumor of the pancreas, and simultaneous measurement of the serum levels of AFP and PIVKA-II will enable earlier diagnosis. This is the first report describing hepatoid carcinoma of the pancreas producing PIVKA-II.

Origin of hepatocellular carcinoma: role of stem cells

The question of whether hepatocellular carcinoma (HCC) arises from the differentiation block of stem cells or dedifferentiation of mature cells remains controversial. Recently, researchers suggested that HCC may originate from the transdifferentiation of bone marrow cells. Interestingly, there are four levels of cells in the hepatic stem cell lineage: bone marrow cells, hepato-pancreas stem cells, oval cells and hepatocytes. Hematopoietic stem cells and the liver are known to have a close relationship in early development. Bone marrow stem cells could differentiate into oval cells, which could differentiate into hepatocytes and duct cells. The development of pancreatic and liver buds in embryogenesis suggests the existence of a common progenitor cell to both the pancreas and liver. Cellular events during hepatocarcinogenesis illustrate that HCC may arise from cells at various stages of differentiation in the hepatic stem cell lineage.

Hepatoid carcinoma of the pancreas

Background

Hepatoid carcinoma of the pancreas is extremely rare. This article tries to summarize the clinical features and outcomes of pancreatic hepatoid carcinoma.

Methods

The data pool for analysis includes the case we encountered with hepatoid carcinoma of the pancreas and the reported cases in the literature.

Results

Twenty-three cases of hepatoid carcinoma of the pancreas were analyzed. This tumor occurred more frequently in male than in female patients (69.6 vs. 30.4 %). Tumor sizes range from 0.5 to 11.0 cm with median of 6.0 cm. The most common symptom was epigastric pain (36.4 %). When the tumor locates at pancreatic head, nausea/vomiting (62.5 %) is more common, followed by jaundice and epigastric pain (50.0 %). For those at pancreatic body-tail, 42.9 % of the patients presented no symptom. Alpha-fetoprotein (AFP) was abnormally elevated in 60 % of the cases. Hepatoid carcinoma in the pancreas could be either pure form or mixed form with other malignancy (40.9 %), with the most common coexisted pathology of malignant neuroendocrine tumor (22.7 %). Metastasis occurred in 36.4 % of the cases at the diagnosis of this tumor, including liver metastasis in 31.8 % and lymph node metastasis in 21.1 %. The overall 1-year survival rate was 71.1 % and 5-year 40.4 %, with a median of 13.0 months. Unresectability, hepatic, and lymph node metastases are associated with negative impact on survival outcome.

Conclusions

Elevation of serum AFP may be a clue leading to the diagnosis of pancreatic hepatoid carcinoma. This tumor could be mixed form with other malignancy. Surgical resection should be the treatment of choice whenever possible.

Hepatoid Carcinoma of the Pancreas

Extrahepatic hepatocellular carcinoma differentiation has been demonstrated in primary malignancies of the stomach. To date, only five cases of hepatocellular differentiation of the pancreas have been reported in the literature. An example of hepatoid carcinoma of the pancreas is reported in this study. A single case of hepatoid carcinoma of the pancreas is presented with long-term follow-up and review of the literature. This rare malignancy of the pancreas represents a hepatocytic transdifferentiation of pancreatic cells to form a combination of both primary ductal adenocarcinoma and hepatocellular differentiation.

Pancreatic-hepatic switches in vivo

The existence of a common endodermal progenitor cell to both pancreas and liver is suggested by anatomy of the development of pancreatic and liver buds in embryogenesis. Here we review the large body of evidence that pancreas to liver and liver to pancreas cell differentiation can also occur in adult life. The published data are consistent with the hypothesis that endodermal progenitor cells, capable of giving rise to multiple hepatic and pancreatic cell types continue to persist. These cells may represent a stem cell reservoir with potential in cell therapy applications in the future.

Multiple loss of heterozygosity without K-ras mutation identified by molecular analysis on fine-needle aspiration cytology specimen of acinar cell carcinoma of pancreas

Fine-needle aspiration diagnosis of pancreatic acinar cell carcinoma (PAC) is challenging. Typically, the cytologic findings in PAC are described as a cellular population of loosely cohesive clusters and single neoplastic cells. The individual cells have granular cytoplasm, uniform nuclei, a fine chromatin pattern, and occasional prominent nucleoli. These features are suggestive of PAC but not diagnostic. We illustrate a case in which the combination of cytopathologic findings, clinical information, and molecular analysis enabled us to arrive at the diagnosis of PAC. Although the cytomorphologic features alone were not specific, the presence of a markedly elevated serum lipase level, cutaneous lesions of fat necrosis, and loss of heterozygosity at 1p, 5q25 at the APC locus, 9p21 at the p16 locus, and 17p13 at the p53 locus were essential in excluding the main differential diagnostic entities including pancreatic ductal carcinoma, pancreatic endocrine tumor, and pancreatoblastoma.

Malignant insulinoma with hepatoid differentiation: a unique case with alpha-fetoprotein production

Hepatoid carcinomas are uncommon extra-hepatic neoplasms exhibiting features of hepatocellular carcinoma and they are most frequently described in the stomach. We report a 64-year-old woman with a malignant insulinoma showing focal hepatoid differentiation and biochemical evidence of alpha-fetoprotein (AFP) production. The current case is the first malignant insulinoma with hepatoid differentiation. Resection of the primary tumor followed by regional embolization was peformed. The patient died 22 months after initial presentation. Thus, the presence of hepatoid differentiation in pancreatic tumor should be noted as the tumor may be associated with elevated AFP. The features of pancreatic hepatoid carcinomas are discussed.

Hepatoid carcinoma of the pancreas

BACKGROUND

The majority of primary extrahepatic neoplasms exhibiting features of hepatocellular carcinoma in terms of morphology, immunohistochemistry, and behavior have been described in the stomach. To the authors' knowledge only a few cases have involved other organ sites. They frequently are associated with other histologic type tumors such as adenocarcinoma, and portend an aggressive behavior.

METHODS

Two examples of hepatoid carcinoma arising from the pancreas are reported in the current study.

RESULTS

One case was a malignant islet cell tumor with a full-blown clinical syndrome of glucagon overproduction, histologic evidence of hepatocytic differentiation, bile production, and alpha-fetoprotein (AFP) positivity. The second tumor was a ductal carcinoma showing periodic acid-Schiff positive and diastase-resistant hyaline globules, AFP production, and ultrastructural resemblance to hepatocytic cells.

CONCLUSIONS

The rare observation of cellular phenotypic transformation that corresponds with the process of hepatocytic transdifferentiation of pancreatic cells demonstrated in animal models and the common embryologic foregut derivation of the pancreas and liver also may explain the phenomenon of pancreatic hepatoid carcinoma.

alpha-Fetoprotein-producing adenocarcinoma of the pancreas presenting focal hepatoid differentiation

We report a rare case of pancreatic carcinoma producing alpha-fetoprotein (AFP), showing focal hepatoid differentiation in metastatic lymph nodes. A 65-yr-old female was admitted because of abdominal pain. The serum AFP was measured at 16,170 ng/mL. Radiological examinations revealed a mass measuring 6 cm in diameter in the body and tail of the pancreas. A right supraclavicular lymphadenopathy was found and biopsied. Light microscopy showed a tumor consisting of a portion of a hepatoid area and well-differentiated adenocarcinoma, which was suggestive of a hepatoid adenocarcinoma. Immunohistochemical analysis showed that the tumor cells expressed AFP, alpha 1-antitrypsin (AT) and albumin. Although the pathological diagnosis of the primary pancreatic tumor was not obtained, this appears to be the first case of hepatoid adenocarcinoma of the pancreas.

Colloid cysts of the third ventricle: immunohistochemical evidence for nonneuroepithelial differentiation

The histogenesis of colloid cysts (CCs) of the third ventricle has been a subject of controversy. We examined, using immunohistochemical techniques, four CCs for the presence of cytokeratins (CKs), glutathione S-transferase isoenzymes (GST-pi, GST-mu), and glial fibrillary acidic protein. Antibodies to both low molecular weight CKs (anti-CK8) and to a mixture of CKs (AE1/AE3) were used. For comparison, normal fetal and adult choroid plexus, ependyma, and nasal mucosa were also examined. The epithelium lining all four CCs showed positive immunostaining for the CKs and GST-pi but not for GST-mu or glial fibrillary acidic protein. Fetal and adult nasal mucosa showed a pattern of immunohistochemical staining almost identical to that of CCs. In contrast, fetal and adult choroid plexus tissue showed positive immunostaining for GST-pi and low molecular weight CKs but not for the CK mixture (AE1/AE3). Fetal and adult ependyma were negative for both CKs and GST-pi. These results suggest that CCs differentiate along nonneural lines distinct from the neuroepithelial differentiation of the choroid plexus and ependyma.

Hepatoid adenocarcinoma of the papilla of Vater

An adenocarcinoma of the papilla of Vater showing hepatoid differentiation similar to that described for hepatoid adenocarcinoma of the stomach is reported. The tumor was a poorly differentiated adenocarcinoma with clear cells containing occasional hyaline droplets and exhibiting bile secretion. Alpha-fetoprotein (AFP), alpha 1-antitrypsin (alpha 1-AT) and carcino-embryonic antigen (CEA) were demonstrated by immunoperoxidase staining. This appears to be the first report of a hepatoid adenocarcinoma at this location.