Experience in primary hepatic neuroendocrine tumor

Background/aims: We aimed to analyze the clinical characteristics, pathologic features, treatment approaches, and prognostic factors of primary hepatic neuroendocrine tumor. Materials and Methods: We retrospectively analyzed the clinical characteristics, pathologic features, treatment approaches, and prognostic factors of 9 patients with primary hepatic neuroendocrine tumor treated in our hospital from January 2003 to January 2010. Results: The clinical manifestations were nonspecific and variable. The most common clinical manifestation was distention or right upper quadrant pain. Radiological findings are not specific and cannot distinguish primary hepatic neuroendocrine tumor from hepatocellular carcinoma. Diagnosis of primary hepatic neuroendocrine tumor was confirmed immunohistochemically and by the absence of extrahepatic primary sites. No extrahepatic primary lesions were found by ultrasonography, computed tomography, magnetic resonance imaging or positron emission tomography scan either pre-operatively or during the follow-up period in our research. Immunohistologically, synaptophysin, chromogranin A and CD56 should be used as markers to precisely diagnose primary hepatic neuroendocrine tumor. The outcome of primary hepatic neuroendocrine tumor is mostly related to its resectability. Total resection of the neoplasm is most commonly proposed. A multimodality of treatments, including chemotherapy, transarterial chemoembolization and radiofrequency ablation, should be used pre- or postoperatively to improve the survival. Conclusions: Primary hepatic neuroendocrine tumor is a rare entity, and its diagnosis is difficult. Preoperative fine needle biopsy is strongly recommended, and primary surgery integrated with chemotherapy, transarterial chemoembolization or radiotherapy is considered to be an effective modality for primary hepatic neuroendocrine tumor.