A case of neuroendocrine carcinoma with massive invasion to the liver and multiorgan causing acute liver failure.

Introduction: Acute liver failure (ALF) due to a malignant neoplasm is rare. Here, we present a case of neuroendocrine carcinoma (NEC) with massive invasion to the liver and multi-organ causing ALF that resulted in a poor outcome. A 56-year-old man was referred to our hospital for ALF of unknown cause. Abdominal imaging studies revealed hepatomegaly with multiple intrahepatic lesions. The patient also showed disseminated intravascular coagulation. Despite administration of prednisolone for the ALF, he died suddenly of respiratory failure on day 3 after admission. Autopsy showed a markedly enlarged liver weighing 4,600 g with diffuse nodular lesions. The tumors had metastasized to the lungs, spleen, adrenal glands, and bone marrow. Severe pulmonary hemorrhage was also noted. Histologically, the tumors were poorly differentiated and composed of small-sized and uniform neoplastic cells, positive for chromogranin A, synaptophysin, CD56, and p53 with a Ki-67 labeling index of over 50%. As there was no primary lesion in the gastrointestinal tract, pancreas, or other organs, primary hepatic neuroendocrine carcinoma (PHNEC) was suspected.

Conclusion: We experienced a case of NEC causing ALF and multi-organ invasion with a rapidly deteriorating course. Liver metastasis from a neuroendocrine tumor/neoplasm is common, while a primary hepatic neuroendocrine tumor/neoplasm is extremely rare. We could not determine PHNEC; however, it was highly suspected. Further studies are needed to elucidate the pathogenesis of this rare disease.