Primary hepatic neuroendocrine tumor — (18)F-fluorodeoxyglucose positron emission tomography/computed tomography findings: A case report

BACKGROUND: Primary hepatic neuroendocrine tumors (PHNETs) are rare hepatic tumors. Their diagnosis, which is based on radiological findings, is difficult. CASE SUMMARY: We present a case of PHNET in a 79-year-old man with no clinical symptoms. Computed tomography (CT) and 2-Deoxy-2-[fluorine-18] fluorodeoxyglucose positron emission tomography/CT ((18)F-FDG PET/CT) were performed for further evaluation. A hypoattenuating mass with rim-like enhancement in segment 6 of the liver was detected on contrast-enhanced CT imaging. Increased uptake was also observed on (18)F-FDG PET/CT. Histopathological and immunohistochemical examinations, which revealed a grade 2 neuroendocrine tumor (NET), confirmed the diagnosis. CONCLUSION: Diagnosing PHNET is challenging, and must be distinguished from other liver tumors. Metastatic NETs should be excluded.