An Unusual Location of Neuroendocrine Tumour: Primary Hepatic Origin

Although neuroendocrine tumours (NETs) of primary hepatic origin are extremely rare, most of NETs present with liver metastasis. When a NET is found in the liver, it must be treated to exclude metastasis from extrahepatic primary sites. The patient was a 38-year-old female. Abdominal ultrasound showed an 8 cm tumour in liver during a routine examination. Liver biopsy was done. The tumour was first considered a metastatic hepatic tumour on histopathological examination. No clues to the origin of a primary tumour were found. Upper and lower endoscopy of the GI tract and chest CT were performed to search for a primary tumour and were negative for any tumour. One month later, more extensive areas of the tumour were seen on histopathological examination of second liver biopsy with the same morphologic characteristics as the first biopsy. Immunohistochemically, there was positive staining for synaptophysin, CD 56, and S-100 in the tumour cells. These findings suggested the diagnosis of NET. The diagnosis of primary liver NET was considered in a multidisciplinary meeting. Then, left hepatectomy was performed. The final pathologic diagnosis of the tumour in the resected liver specimen was Grade II NET. The patient was doing well at postoperative 28-month follow-up.