Status of the Gastric Mucosa with Endoscopically Diagnosed Gastrointestinal Stromal Tumor

Background. Since gastrointestinal stromal tumor (GIST) is a mesenchymal submucosal tumor, the endosonographic, CT, and MRI features of gastric GISTs have been widely investigated. However, the GIST-bearing gastric mucosa status has not been reported. Objective. To characterize the GIST-bearing gastric mucosa status in terms of the degree of inflammation and atrophy, assessed endoscopically. Subjects and Methods. The subjects were 46 patients with submucosal tumors (histologically proven gastric GISTs) who had undergone upper gastrointestinal endoscopy in our hospital between April 2007 and September 2012. They were retrospectively evaluated regarding clinicopathological features, the endoscopically determined status of the entire gastric mucosa (presence or absence and degree of atrophy), presence or absence and severity of endoscopic gastritis/atrophy (A-B classification) at the GIST site, and presence or absence of H. pylori infection. Results. Twenty-three patients had no mucosal atrophy, but 17 and 6 had closed- and open-type atrophy, respectively. Twenty-six, 5, 12, 1, 1, and 1 patients had grades B0, B1, B2, B3, A0, and A1 gastritis/atrophy at the lesion site, respectively, with no grade A2 gastritis/atrophy. Conclusion. The results suggest that gastric GISTs tend to arise in the stomach wall with H. pylori-negative, nonatrophic mucosa or H. pylori-positive, mildly atrophic mucosa. 1. Introduction Gastric gastrointestinal stromal tumor (GIST) is a mesenchymal tumor arising from the muscularis propria of the gastric wall and is covered with normal mucosa, giving the endoscopic appearance of a submucosal tumor with bridging folds. Since gastric GIST is a submucosal tumor, its endosonographic, CT, and MRI features have been widely investigated [1–4]. However, the status of the GIST-bearing gastric mucosa itself has not been reported. Based on our experience, many GIST patients often show no evidence of H. pylori infection, gastritis, or mucosal atrophy on upper gastrointestinal endoscopy, and even H. pylori-infected patients may show mild gastritis in the background gastric mucosa. We consider that it is necessary to evaluate the GIST-bearing gastric mucosa using available data before testing the validity of this empirical rule and investigate the reason for it, if it is valid. In this study, we retrospectively evaluated patients with submucosal tumors (histologically proven gastric GISTs) regarding the age, gender, site and size of the lesion, risk classification of GISTs, presence or absence and degree of endoscopic atrophy in the entire gastric