Ectopic hepatocellular carcinoma arising from pancreas: A case report and review of the literature

Abstract

A 56-year-old man was found to have a pancreatic tail tumor. His blood chemistry showed no infection with hepatitis B or C virus and no elevations of tumor markers or pancreatic hormones. Abdominal ultrasound showed an encapsulated, rather heterogeneous, hypoechoic tumor, 6.5 cm in maximum diameter, with a beak sign. Helical dynamic CT revealed an irregularly enhanced tumor with pooling of contrast medium in the delayed phase. Abdominal angiography showed a hypervascular tumor. With a tentative diagnosis of non-functional islet-cell tumor, the patient underwent resection of the pancreatic body and tail with splenectomy. The contour of the liver and its surface were normal. In microscopic examination, tumor cells arranged in a trabecular pattern with focal bile pigment resembling hepatocellular carcinoma (HCC). Immunohistochemically, these tumor cells were positivefor HEPPAR-1, CAM5.2, cytokeratin 18 and COX-2, but negative for MUC-1, and cytokeratins 7, 20 and 8. These results supported a diagnosis of HCC without any adenocarcinoma component. The patient is currently doing well without any signs of recurrence in either the remaining pancreas or liver three years after surgery. We report the rare case with ectopic HCC in the pancreas with a review of the literature.

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

“…(2,(4)(5)(6)(7)(8)(9)(10) The clinical and pathological features of these cases and our present case are summarized in the Table. (2,4-10)…”

“…The crucial distinguishable feature is whether the tumor has residual normal liver tissue. (9,10) However, there was no normal liver tissue in both cases classified as pancreatic ectopic hepatocellular carcinoma in the literature. Therefore, the distinction between hepatoid carcinoma and ectopic hepatocellular carcinoma remains somewhat arbitrary.…”

“…(9,10,16) The latter occurs rarely and as a late event, so the original hepatic tumor is usually obvious at presentation. (16) Thorough clinical evaluation and imaging excluded this possibility in the current case.…”

“…Although there was no solid evidence, the lack of normal liver tissue around the microcarcinoma favors the possibility of a malignant change of metaplastic cells from uncommitted stem cells rather than from handicapped ectopic liver tissue. (2,9,10) Because of the obscurity of the difference between pancreatic pure hepatoid carcinoma and ectopic hepatocellular carcinoma, pancreatic carcinomas with pure hepatoid features might be regarded as the same group.…”

“…In the pancreas, hepatoid carcinomas are regarded as a heterogeneous group of tumors with or without another histological component, and carcinomas with pure hepatocytic features have been designated variously as hepatoid carcinoma or ectopic hepatocellular carcinoma. (2)(3)(4)(5)(6)(7)(8)(9)(10) To date, only eight such pancreatic carcinomas have been reported. Herein, we describe the ninth case which was small.…”