4541 Clinical significance of gastritis cystica polyposa and role of endoscopic ultrasonography.

Background:Gastritis cystica polyposa(GCP) is one of multiple cystic lesion in mucosa(superficialis) and/or submucosal layer(profunda) of stomach. This lesion has been regarded as a benign lesion. However, some authors have reported that gastric cancer and adenoma is arising from GCP, and gastric cancer associated with gastric cystic lesion has also been described. Endoscopic ultrasonography(EUS) is the best diagnostic tool to evaluate small gastric cystic lesion, and it can give exclusive information for gastric tumor lesions associated with gastric submucosal cystic lesion at preoperative state. The aim of this study was to evaluated the typical EUS findings of GCP, the efficacy of EUS as diagnostic tool in GCP and its related tumor lesions. Patient and method:From Jan 1995 to November 1999, we have tried 1350 cases of endoscopy and EUS to differentiate gastric protruding or elevated lesion, 9 cases of GCP was confirmed by endoscopic resection or operation. We analysis clinical features and diagnosis in gastrofiberoscopy and EUS, compare to histologic diagnosis. Results: Clinical symptoms of GCP are abdominal discomfort or indigestion in all GCP patients. Operative history of subtotal gastrectomy was noted in only 3 cases of GCP. Initial endoscopic diagnosis to GCP was incomplete in all cases. Endoscopic findings of GCP are various; 3 gastric polyp, 2 SMT, 2 flat elevated lesion, 1 hypertrophic gastritis, and 1 small polyp coexist with gastric cancer. We could diagnosed GCP in 8 patients through EUS(sensitivity 88.9%, positive predictable rate is 100%). EUS findings is characterized by 14.1mm(9-26) of mean size, multiple variable sized anechoic lesion with intervening hyperechoic structure(8 cases), irregular margin(7), musoca and submucosal thickening(6), and submucosal invasion(5 GCP profunda). In histologic findings, 6 GCP were associated with underlying gastritis only, but two gastric tubular adenomas were located in mucosa above cystic dilatation of gastric gland. One small GCP lesion was noted in other site of upper body in patient with early gatric cancer. Conclusions:EUS is an effective diagnostic tool to evaluate and differentiate GCP from the protruding and elevated gastric lesion, and an important role to decide method of management of GCP. EUS is monopolistic diagnostic procedure to evaluate GCP associated with gastric tumor lesions before resection, and more clinical usefulness of EUS is expected to lighten pathogenetic relationship in these two disease entities in future.