Cystic Hepatic Neuroendocrine Tumor: A Rare Entity

A 70-year-old man presented with unspecific abdominal symptoms and weight loss was referred for a sonographic examination. Sonography revealed 3 cystic hepatic masses in an otherwise unremarkable liver. Contrast-enhanced MRI of the liver was performed to characterize the hepatic lesions and elucidate their etiology. The differential diagnosis was primarily parasitic disease or metastases with cystic transformations. 68Ga-DOTATOC PET/CT revealed the neuroendocrine origin of these lesions, confirmed by biopsy. However, the primary site of the neuroendocrine tumor remained unclear, leaving primary hepatic neuroendocrine tumor and neuroendocrine cancer of unknown primary as possible diagnostic options.