2346 Primary Neuroendocrine Tumor of the Porta Hepatis in a Patient With Crohn’s Disease

Abstract

INTRODUCTION: Well-differentiated neuroendocrine tumors (NETs) are rare entities usually of the GI tract and lung. A small subset of NETs have been identified in the biliary tree and liver, and large majorities of these are identified due to high concentrations of somatostatin receptors. We describe the rare case of a patient with Crohn’s disease and a primary porta hepatis NET. CASE DESCRIPTION/METHODS: An 80 year-old female with PMH of Crohn’s disease status post small bowel resection x3 and 30-pack year smoking history presented to clinic with a 5-year history of intermittent RUQ/mid-epigastric pain with known 2 cm liver mass. She denied any weight loss or changes in appetite or bowel habits. Abdominal US revealed a porta hepatis mass with a patent portal vein. Abdominal CT revealed mild diffuse infiltration of the liver and a 4.1 × 3.5 × 3.2 cm porta hepatis mass. The common bile duct measured 10 mm with thickening and irregularity of the antrum, pylorus, and proximal duodenum. There was moderate mesenteric lymphadenopathy. Biopsy of the porta hepatis mass revealed a low/intermediate grade NET of possible GI or pancreatic origin. Urine 5-HIAA was normal, and octreotide scan revealed abnormal activity in the area of the porta hepatis only. EGD revealed H. pylori (+) gastritis, and colonoscopy was normal. The patient underwent exploratory laparotomy revealing biliary invasion and positive metastatic lymph nodes. Open cholecystectomy was performed, and the patient underwent ERCP with common bile duct stent placement. DISCUSSION: Well-differentiated NETs are particularly rare. In a National Cancer Institute series, age-adjusted incidence for non-pancreatic primaries was 4.7 per 100,000. Most primary NETs are located in the GI tract (55%) and bronchopulmonary system (30%) and tend to metastasize to the liver. Patients may experience pain, jaundice, early satiety, flushing, or diarrhea. Our patient’s only complaint was pain. Despite an extensive workup to stage the cancer and identify a potential primary, no additional culprit lesion was identified. Immunohistochemical staining and/or molecular classifier assays of the specimen can be helpful to identify the primary site but are not definitive. We believe this is a primary hepatic lesion which is very rare. Metastasis to the biliary tree and hilar lymph nodes portends a poorer prognosis. Our patient was started on Somatuline. Somatostatin analogs are highly effective in controlling symptoms associated with advanced GI NETs.