Primary hepatic neoplasms arising in cirrhotic livers can have a variable spectrum of neuroendocrine differentiation.

Primary hepatic neoplasms with neuroendocrine differentiation are extremely rare. Their clinicopathological features and molecular genetic basis are largely unknown. We identified four cases of primary hepatic neoplasms with neuroendocrine differentiation. Electronic medical records were reviewed for clinical history, imaging findings, laboratory results, and follow-up. Pathology slides, immunohistochemistry, and ancillary studies were reviewed. There were two females and two males with age ranging from 52 to 74 years. There was one amphicrine carcinoma with tumor cells simultaneously demonstrating both hepatocellular and neuroendocrine differentiation, one mixed hepatocellular-neuroendocrine carcinoma (NEC) with hepatocellular component intermingled with neuroendocrine component, one small cell NEC, and one well-differentiated neuroendocrine tumor. Next- generation sequencing of the mixed hepatocellular-NEC and small cell NEC showed molecular/genetic alterations commonly seen in hepatocellular carcinoma (HCC). All four cases arose in a background of cirrhosis. Primary hepatic neoplasms arising in cirrhotic livers can have a spectrum of neuroendocrine differentiation. Presence of a NEC component may be an indicator of aggressiveness. In addition, primary hepatic carcinomas with neuroendocrine differentiation likely share the same molecular pathways as HCC.