Case Report: Zollinger-Ellison Syndrome

Abstract

Purpose: Zollinger-Ellison syndrome (ZES) is caused by a non-beta islet cell, gastrin-secreting tumor that stimulates the acid-secreting cells of the stomach to maximal activity, with consequent gastrointestinal mucosal ulceration. ZES may occur sporadically or as part of the autosomal dominant familial syndrome, multiple endocrine neoplasia type 1 (MEN 1). The primary tumor is usually located in the duodenum, the pancreas, and abdominal lymph nodes, but ectopic locations have also been described. We present a 67 year old African American male who had multiple admissions to the hospital with complaints of frequent nausea, vomiting, diarrhea. He then presented with hematemesis and severe abdominal pain and on EGD was found to have multiple clean-base ulcers in the descending duodenum along with severe esophagitis. An antral biopsy was negative for H.pylori. Serum gastrin level was found to be 6893 pg/ml. The patient underwent an Endoscopic Ultrasound (EUS) that revealed a hypoechoic mass seen in the peri-duodenal area. The mass measured 53.4 mm x 34.5 mm in diameter. FNA of the mass was performed. Cytology showed a neuroendocrine tumor staining weakly positive for chromogranin and strongly positive for synaptophysin. An octreotide scan showed persistent right upper quadrant uptake suggestive for a somatostatin sensitive lesion with no evidence of metastatic disease. MRI of abdomen showed a 4 cm mass between the duodenum and the head of the pancreas. The patient underwent surgical resection of the tumor that was found to be attached to the head of the pancreas. The final surgical pathology confirmed the diagnosis of pancreatic neuroendocrine tumor with features of gastrinoma. ZES occurs in approximately 0.1-1% of all patients with duodenal ulcers. Currently, the morbidity and mortality of ZES is low because of improved medical and surgical management of the disease. Fewer than 5% of patients develop a complication, such as abdominal perforation, gastric outlet obstruction, or esophageal stricture. Fasting serum gastrin is the best single screening test. Endoscopic ultrasound is one of the most sensitive methods for localizing gastrinomas. In the absence of metastatic disease, surgical resection is the treatment of choice.