Giant type III well-differentiated neuroendocrine tumor of the stomach: A case report

We describe a case of a large type III neuroendocrine tumor of the stomach. Management and current literature are reviewed.

A 37year old female presented with upper gastrointestinal bleed and epigastric pain. Further workup demonstrated a large ulcerated gastric mass near the GE junction. Computer tomography scan and endoscopic ultrasound showed a 10cm mass with no evidence of distant disease. Fine needle aspiration pathology was consistent with a well differentiated neuroendocrine tumor (Ki67 index<2%), with elevated levels of chromogranin A and serotonin levels but normal gastrin. The patient underwent an uneventful total gastrectomy. Final pathology analysis reported a higher KI67 index (7.54%) and a final pathology of grade 2 type III, T3 N3, neuroendocrine tumor of the stomach. The chromogranin levels normalized and no recurrent disease has been detected in one year follow up.

Gastric neuroendocrine tumors are extremely rare, accounting for 4% of all neuroendocrine tumors of the body and 1% of all neoplasms of the stomach. Based on histomorphologic characteristics and pathogenesis, gastric neuroendocrine tumors are classified into four types with differing prognosis and behavior. Current literature describes type 3 gastric neuroendocrine tumors as larger than 2cm. However, there is no precedent in the literature for a tumor of this size.

The incidence of gastric neuroendocrine tumors has been increasing during the last decade, underscoring the need to improve our understanding of their biology and behavior. When identified histologically, patient outcomes depend on appropriate determination of tumor biology and subsequent choice of treatment.