Pancreatic hepatoid carcinoma: A case report and literature review

Abstract

Hepatoid carcinomas (HCs) are a group of heterogeneous tumors that are similar to hepatocellular carcinoma (HCC). Pancreatic hepatoid carcinoma (PHC) is a very rare disease. The present study presents the case of a 63-year-old male patient with PHC with synchronous liver, spleen and stomach metastasis, in an aim to enhance our understanding of this disease. A 63-year-old male presented with abdominal distension for 3 months and slightly developed asthenia and anorexia. Laboratory tests of serum tumor markers revealed the alpha fetoprotein level was markedly elevated (>10,00.0 ng/ml). The radiological findings of computed tomography, magnetic resonance imaging, diffusion-weighted imaging and magnetic resonance cholangiopancreatography revealed a malignant tumor in the tail of the pancreas with synchronous liver, spleen, stomach and retroperitoneal lymph node metastasis. A post-operative immunohistochemical analysis revealed that the tumor cells in the tail of the pancreas exhibited positivity for glypican-3; right liver positivity was also observed for CK-18 and weak positivity for glypican-3, suggestive of primary PHC. On the whole, PHC is very rare, and exhibits morphological features similar to those of HCC. Its diagnosis is mainly achieved via morphological analysis and immunohistochemical staining of the tissue specimens, since the clinical manifestation and laboratory test results are often unspecific.

Focal Hepatocellular Carcinoma in Pancreas

“…In a recent literature review of 41 cases, four histological subtypes were noticed: pure HCC-like morphology, with neuroendocrine differentiation, and with acinar or glandular differentiation [ 4 ]. Different terms have been used for the subtype with pure HCC such as hepatoid carcinoma, hepatic adenocarcinoma, hepatoid variant of pancreatic cancer, primary HCC of the pancreas, a pancreatic tumor with hepatoid differentiation or ectopic HCC, etc.…”

“…HC has a histological appearance of proliferating large tumor cells, with a trabecular pattern of large polygonal cells seen with abundant eosinophilic cytoplasm, central nuclei, and nucleoli [ 12 ]. A majority of PHC cases have elevated serum AFP levels, hence it can be used as a marker to determine the success of surgery or response to chemotherapy [ 4 ]. Certain primary pancreatic cancers can have elevation in AFP levels, including ductal carcinoma, neuroendocrine, germ cell tumors and undifferentiated pancreatic adenocarcinoma [ 13 , 14 ].…”

“…Hep Par-1 is thought to be the most sensitive among these markers [ 18 ]. Metastatic HCC from the liver and HC from another site are the closest differentials [ 4 ]. Two specific hepatocyte transporters i.e., bile salt export pump (BSEP) and multidrug resistant protein 3 (MDR3) which are only expressed by HC cells, have been suggested to differentiate [ 14 ], but they are not available everywhere.…”

“…It was first described in the stomach in 1985 [ 2 ] and pancreatic hepatoid carcinoma (PHC) was described in 1999 [ 3 ]. Primary sites such as the stomach, esophagus, lungs, gall bladder, urinary bladder, colon, ampulla of Vater, uterus, fallopian tubes, adrenal glands, ovaries, thymus, biliary tract, and other sites have been reported with HC [ 4 , 5 ], with stomach being the most common location [ 5 ]. It is a very rare occurrence in the pancreas.…”

“…To the best of our knowledge, less than 50 cases of PHC have been reported so far in the literature. A review of literature shows that the diagnosis of PHC is mainly achieved through morphological analysis and immunohistochemical staining of the tissue specimens, since the clinical manifestations and laboratory tests are non-specific and it does not have unique radiological characteristics to set it apart from other pathologies [ 4 ]. Even the special staining required for its diagnosis might not be available at every institution.…”