Primary hepatic neuroendocrine carcinoma in a baboon (Papio sp.)

Abstract

Background: Primary neuroendocrine carcinomas of the liver have rarely been reported in humans and domestic animals, but not in non-human primates.

Methods: We describe the morphologic and immunohistochemical features of a primary hepatic neuroendocrine carcinoma found in a 29-year-old female baboon.

Results and conclusions: The neoplasm was characterized by multiple solid nodules that were multifocally distributed in the liver. Metastases were not observed. Histologically, the neoplasm was composed of cords and nests of epithelial cells arranged in a neuroendocrine pattern, occasionally forming glandular and rosette-like structures. On immunohistochemical evaluation, the neoplastic cells were immunopositive for pancytokeratin, chromogranin A, neuron-specific endolase, and synaptophysin and were negative for vimentin, S100 protein, glucagon, and insulin.

Fig. 1

Hepatic neuroendocrine carcinoma. Note the multifocal distribution of variably sized neoplastic nodules in the liver parenchyma.

Fig. 2

Hepatic neuroendocrine carcinoma. Note the islands of neoplastic cells forming rosettes occasionally containing homogeneous, eosinophilic material. HE stain. Bar = 50 μm.

Fig. 3

Hepatic neuroendocrine carcinoma. Neoplastic cells are strongly immunoreactive for chromogranin A. Immunohistochemical staining for chromogranin A by the avidin-bioin-horseradish peroxidase (ABC) method. Bar = 50 μm.