Primary Neuroendocrine Tumor of the Liver With Papillary Features in a Multivisceral Transplant Patient.

Primary neuroendocrine tumors (NETs) of the liver are rare and difficult to distinguish from other liver tumors such as cholangiocarcinoma and hepatocellular carcinoma. The patient was initially diagnosed with a NET of the liver in 2007. However, the origin of the cancer was not clear, that is, whether it was primary or originated from the gastrointestinal tract. Although the patient underwent partial hepatectomy, he suffered hepatic artery injury, resulting in biliary strictures. The patient eventually became untreatable and developed cirrhosis, a frozen abdomen. He received multivisceral transplantation in May 2019 and received the liver, duodenal-pancreatic complex, spleen, small bowel, and right colon. After the transplantation, the patient did well overall. More recently, he presented with food poisoning and underwent evaluation, and was found to have a mass in the liver. The liver mass was biopsied and revealed a poorly differentiated primary NET (grade 2) with ciliated papillary structures.