P-LUM-02: Gastric duplication cyst diagnosed with endosonography and managed with modified endoscopic mucosal resection in one session of endoscopy

BACKGROUND AND OBJECTIVES: Duplication cyst of gastrointestinal tract is uncommon, especially stomach. Most cases were identified incidentally while receiving endoscopy for other unrelated signs and symptoms. Most gastrointestinal duplication cysts are asymptomatic, and sometimes, hemorrhage could be presented if the overlying mucosa is eroded. Here, we presented a case of gastric duplication cyst presented as a subepithelial tumor on esophagogastroduodenoscopy (EGD) and we performed endosonography (EUS) for diagnosis and modified endoscopic mucosal resection (EMR) for treatment in one session of endoscopy. CASE REPORT: A 43-year-old female presented to our outpatient department for a second opinion about the management of a gastric subepithelial tumor. She received an EGD for health examination and a gastric subepithelial tumor over antrum was identified incidentally. EUS was scheduled and it demonstrated an anechoic homogeneous lesion arising between muscularis mucosae layer (second layer) and submucosa layer (third layer) on the anterior wall of the antrum (size: 8.3 mm × 4.7 mm). Duplication cyst of the stomach was impressed, and we removed it with modified EMR subsequently in one session of endoscopy. Histology disclosed two cystic lesions lined by single layer of gastric type mucosal epithelium and walled by well-developed smooth muscle layers, consistent with duplication cyst and gastric duplication cyst, was diagnosed. CONCLUSION: Gastric duplication cyst could be diagnosed with EUS, and modified EMR is an option for management.