Clinicopathological Study on Endocrine Cell Micronests Associated with Early Gastric Cancer

Abstract

Objective The purpose of this study was to review cases of early gastric cancer associated with Endocrine cell micronests (ECM) and investigate the incidence and characteristics of these lesions.
Methods A total of 482 patients who had undergone endoscopic or surgical resection for gastric epithelial neoplasms from April 2008 to March 2010 were enrolled in this study. After detection of ECM in the lamina propria mucosa by histological examination of the resected specimens with hematoxilin-eosin staining, immunostaining was also performed. Clinical manifestation and endoscopic findings, as well as histological findings, were examined.
Results Among the 482 patients, 5 (1.0%) had ECM. The histological type of gastric epithelial cancers associated with ECM was tubular adenocarcinoma and carcinoma in situ (Tis) in the WHO classification in all 5 cases. ECM were round to oval or trabecular and located within the area of the early gastric cancer in all the 5 cases. The background gastric mucosa was Type A gastritis in 2 patients and ordinary atrophic gastritis in 2 patients. In the other case, it was difficult to determine the type of gastritis.
Conclusion ECM developed not only from the background of Type A gastritis but also from ordinary atrophic gastritis. ECM coexistent with gastric cancer were present in 1.0% of resectable gastric epithelial neoplasms.