(253) Unusual Case of Hepatic Neuroendocrine Carcinoma in a Patient With a Perforated Gastric Ulcer

Introduction: Neuroendocrine tumors (NETs) originating from enterochromaffin cells of the neuroendocrine system are rare. They primarily occur in the gastrointestinal tract, pancreas, and lungs and often metastasize to the liver. However, primary hepatic neuroendocrine tumors (PHNET) do occur very rarely, with less than 200 cases documented in the literature. Due to their rarity, unique clinical features, and nonspecific symptoms, they are difficult to correctly diagnose. In this case report, we review a case of a patient presenting with gastric ulcer perforation and an incidental finding of a liver tumor suspected to be high grade neuroendocrine carcinoma small type.

Methods: A 47-year-old male with history of tobacco use, chronic NSAID use, and prior ventral hernia repair presented with peritonitis, pneumoperitoneum, and hepatomegaly with heterogeneity of liver. He was taken emergently to the operating room where an omental (Graham) patch repair of the perforated gastric ulcer was performed. His liver appeared enlarged, engorged, and infiltrated with a diffuse, congestive process. Due to concern for underlying malignancy, we performed a wedge liver biopsy.

Results: The liver biopsy showed diffusive nests and sheets of small blue cells with extensive apoptosis and necrosis, and brisk mitotic activities. Immunostains were positive for CK7 and synaptophysin, negative for chromogranin, CK20, and p40. Ki-67 proliferative index was very high (95%). Based on morphology and immunoprofile, the tumor was best defined as high grade neuroendocrine carcinoma, small cell type. While inpatient, he went into multi-system organ failure, and expired prior to formal oncologic work-up, which would have determined if his hepatic neuroendocrine carcinoma represented primary or metastatic disease.

Conclusions: Neuroendocrine tumors are a rare gastrointestinal malignancy, and PHNETs are extremely rare, making up less than 1% of resected primary liver tumors. As illustrated by this patient, whose diagnosis was incidentally discovered during a perforated gastric ulcer repair, these cases are difficult to detect. In this case report, we review current literature of hepatic neuroendocrine carcinoma, discuss diagnosis and treatment of these rare tumors, and suggest areas for improvement in the management of these complex tumors.