Autoimmune atrophic gastritis associated with gastric neuroendocrine tumor
Introduction (case reports only) Autoimmune gastritis (AIG) is a special type of chronic gastritis wherein autoimmune disorders caused by cellular immunity result in loss of parietal cells and production of an antiparietal cell antibody (PCA) against the proton pump. This condition is associated with Type-1 gastric neuroendocrine tumor (G-NET) secondary to achlorhydria and hypergastrinemia. G-NETs are rare neoplasms with origin in the peripheral neuroendocrine system in the stomach. Annual incidence of G-NET is 0.68% per person-year. Case description (case reports only) 45-year-old female complained with nausea and acid reflux. Laboratory tests revealed an elevated chromogranin A (720 μg/L), gastrin (>600 pmol/l) and positive PCA (1:100). Esophagogastroduodenoscopy (EGD) was performed and displayed a severely atrophic lining of the stomach body, two 0,3 cm polyps and hyperemic spots. Additionally to polypectomy several biopsies were taken to test for NET, H. Pylori and inflammation. Histological examination of polyp confirmed active G-NET G1, chronic atrophic gastritis with intestinal metaplasia in stomach lining, H.Pylori was negative. Somatostatin analogue scintigraphy was performed for NET recurrence, but no metastasis were detected. Prospectively chromogranin A (463.09 μg/L) decreased. No specific treatment was intended, patient was recommended a follow-up EGD and monitoring for B12 anemia. Summary (case reports only) In this case we presented a patient with non-specific gastroenterological symptoms. Laboratory findings suggested possible autoimmune gastritis with NET, therefore EGD was performed and biopsies were taken. Histological results confirmed the suspected diagnosis. Characteristic clinical findings were related to type 1 G-NET. Conclusions The significance of diagnosing AIG is to include patients as a high-risk group for the development of gastric NETs. Identifying the type of G-NETs is a collective effort of clinical and pathologic correlation. Correct grading and staging of these lesions is significant for treatment and prognosis. Type I lesions are treated by endoscopic mucosal resection. Supplementing vitamin B12 is recommended.