Combined primary hepatic neuroendocrine carcinoma and hepatocellular carcinoma with aggressive biological behavior (adverse clinical course): A case report

Combined primary hepatic neuroendocrine carcinoma (PHNEC) and hepatocellular carcinoma (HCC) is a very rare malignant hepatic tumor. Its prognosis and histological features are uncertain. Here we report the case of such a tumor in a 70-year-old male Japanese patient with adverse prognosis. The patient underwent a right hepatic lobectomy for a tumor mass that measured 11 × 10 cm in diameter located in the right lobe of the liver, treated with transcatheter arterial chemoembolization (TACE) and percutaneous transhepatic portal vein embolization (PTPE) therapy five weeks before the operation. Histologically, the hepatic tumor was composed of predominantly HCC and admixed with a small part of neuroendocrine carcinoma (NEC). The NEC component was distributed as a collision-type tumor separated by fibrous bands from HCC and the combined-type tumor, focally intermingling with HCC. One month after the surgery, metastasis to abdominal lymph nodes and the lumbar vertebra was detected. Although the additional treatments of systematic chemotherapy and radiation therapy were performed, the patient died 3 months after the initial surgery.