S3718 A Case of Chronic Atrophic Gastritis Leading to Gastric Neuroendocrine Tumor

Abstract

Introduction: Neuroendocrine tumors are a rare cancer type that form in neuroendocrine cells. They can occur anywhere in the body, most commonly found in the gastrointestinal tract, bronchopulmonary system, and pancreas. Gastrointestinal NETs (GNETs) are slow-growing tumors that arise from enterochromaffin-like cell tumors and contain chromogranin, synaptophysin, and neuron-specific enolase and can develop throughout the GI tract. Case Description/Methods: 73-year-old female with a prior history of chronic atrophic gastritis with initial presentation of Iron deficiency anemia who underwent EGD and Colonoscopy. Was found to have small bleeding gastric mass on EGD, revealed Type 1 gastric carcinoid tumor on biopsy. She had a (+) anti-parietal cell antibody titer as well as elevated gastrin level. She underwent a partial gastrectomy, the pathology revealed a well-differentiated NET. Her chromogranin level was much higher compared to post surgery levels. It was recommended to continue with only yearly endoscopic surveillance. Discussion: NET features both nerve cells and endocrine cells. Most of the NETs are hormone-secreting and others are associated with hereditary genetic syndromes like multiple endocrine neoplasia type 1 and neurofibromatosis type 1. Although in roots of carcinogenesis, mutation and genetic changes play a central role, hormones can certainly predispose or amplify the process of cancer formation. GNETs have been classified into three different subtypes based on clinical characteristics: Type I, II and III GNETs. Type I GNETs are related to chronic gastritis with hypergastrinemia and enterochromaffin-like cell hyperplasia. Although GNETs remain rare tumors, the incidence of Type 1-GNETs has increased significantly, accounting for about 70-80% of all diagnosed GNETs. This case demonstrates importance of surveillance for NET in patients with chronic atrophic gastritis due to increasing prevalence and incidence. Once diagnosed, endoscopic surveillance and endoscopic removal are reasonable approaches in a surveillance strategy. The optimal interval of such interventions remains to be determined. It is important to emphasize using cost effective yet efficient diagnostic modality in order to identify lesions with predilection for G-NETS early in its course for better outcomes and treatment. As these tumors become better characterized and recognized in the future, societal guidelines for surveillance for GNETs associated with chronic atrophic gastritis will be of benefit.