Primary hepatic neuroendocrine tumors: clinical characteristics and imaging features on contrast-enhanced ultrasound and computed tomography

Primary hepatic neuroendocrine tumor (PHNET) is an extremely rare liver neoplasm, and its clinical characteristics and imaging features are not well understood. The aim of this study was to analyze the clinical profiles and imaging features of PHNETs on contrast-enhanced ultrasound (CEUS) and computed tomography (CT) METHODS: Patients with PHNET between January 2008 and December 2015 were retrospectively identified, and their demographics, laboratory data, and imaging characteristics on CEUS and CT analyzed.

Ten consecutive patients with PHNETs were included (including one G1, seven G2, and two G3 of tumor grades).The median age of patient was 45 years (range: 27-72 years), and 60.0% of patients were male. The most common symptom was abdominal pain (60.0%), and cirrhosis was found in 40.0% of patients. Tumors were confined within the liver in 60.0% of patients, while the remaining patients had extra-hepatic metastasis. The tumors revealed hyperechoic in 60% of patients and mixed echoic in 30% of patients on conventional US, displaying intense arterial enhancement followed by washout in the portal and/or the late phases in 80.0% of patients on CEUS and 60% at CT.

Although PHNET is a very rare liver tumor, it should be considered as a possible differential diagnosis in the management of hepatic tumors. Most PHNETs were hyperechoic or mixed echoic on conventional US, showing similar enhancement patterns to that of hepatocellular carcinoma on CEUS.