Liver resection for primary hepatic neuroendocrine tumours: Report of three cases and review of the literature

Diagnostic Imaging of Primary Hepatic Neuroendocrine Tumors: A Case and Discussion of the Literature

“…Neuroendocrine neoplasms are a relatively rare tumor of the gastrointestinal system, accounting for less than 2% of all GI neoplasms [6]. PHNETs are exceedingly rare, with less than 300 cases reported in the literature to date [3].…”

“…While the origin of PHNETs remains unclear, three hypotheses have been proposed: (1) they arise from neuroendocrine cells scattered in the epithelium of the intrahepatic biliary tract; (2) they originate from heterotopic pancreatic or adrenal tissue located in the liver; and (3) they arise from the neuroendocrine differentiation of a single malignant stem cell that is the precursor of other hepatic tumors [6]. …”

“…They are more frequent in women and more likely to affect the middle-aged population [6]. PHNETs appear most often as an endocrinologically silent hepatic mass or masses.…”

“…This can be contrasted with hepatic metastases from extrahepatic NETs that are more commonly associated with typical carcinoid syndrome. The syndrome itself occurs as a result of the systemic release of neurosecretory products including primarily serotonin, but also histamine, bradykinin, and prostaglandins, and is characterized by flushing and diarrhea [6]. It remains unknown why primary NETs of the liver frequently remain endocrinologically silent while their metastatic counterparts do not.…”

Primary hepatic neuroendocrine tumor: Five cases with different preoperative diagnoses

“…In patients with PHNET, the tumor may be found incidentally during routine screening. While abdominal pain and palpable mass in the right upper quadrant are the most frequent symptoms, the symptoms of carcinoid syndrome may be exhibited, even if it is rare (8). This syndrome is found in less than 10% of the gastrointestinal NETs; however, when it is found, it is always associated with hepatic metastasis.…”