Primary hepatic neuroendocrine tumor: Five cases with different preoperative diagnoses

Neuroendocrine tumors, also known as carcinoid tumors, behave like benign tumors; however, they show the characteristics of carcinoma. While more than 80% of the neuroendocrine tumors found in the liver are metastatic, primary hepatic neuroendocrine tumors are very rare. Five patients with hepatic mass who admitted to our clinic between August 2003 and July 2007 were treated surgically. Ultrasonography, computerized tomography and magnetic resonance imaging were performed in all patients. Endoscopy and colonoscopy were conducted to exclude malignancy of other sites. Hepatectomy was carried out in all patients. Diagnosis was confirmed with immunohistochemical examination. The five patients treated surgically were diagnosed as primary hepatic neuroendocrine tumor histopathologically. Abdominal pain was the most common complaint of all patients. Hepatectomy was conducted in all patients due to tumors originating from the liver lobes. Only one patient (Case 2) underwent transarterial chemoembolization before hepatectomy to reduce tumor bleeding. Owing to tumor recurrence on the left lobe of the liver in Case 2, transarterial chemoembolization was performed four years after hepatectomy. R0 resection was achieved in two patients (Cases 1 and 3). In conclusion, primary hepatic neuroendocrine tumors are very rare and asymptomatic tumors. Thus, high-sensitive laboratory and imaging examinations are required. At present, hepatectomy remains the main treatment for primary hepatic neuroendocrine tumor.