Gastric duplication cysts: literature review and a case report of rare multiple gastric duplication cysts treated by endoscopic submucosal dissection.

Gastric duplication cysts (GDCs) are rare structural abnormalities, especially in adults. We first report a rare case of small multiple GDCs in a woman, which presents as a submucosal tumor (SMT) at the gastric antrum. In consideration of the patient's request for surgical treatment and minimally invasive resection, endoscopic submucosal dissection (ESD) was performed to remove the cyst. The case provides a reference for ESD surgery to remove small GDCs. So far, there is no consensus or practice guidelines for the diagnosis and management of GDCs. Herein we perform a comprehensive literature review and discussion on GDCs. GDCs are 'repetitive' cystic or tubular structures of gastric mucosa and muscularis mucosae, and share the muscularis propria and serous layer with the normal gastric wall. GDCs protruding into the stomach cavity can be diagnosed by endoscopic ultrasound (EUS), which has higher specificity and accuracy than CT and MRI. Some GDCs may cause complications, even cancerization. Therefore, we suggest that once found, the GDCs could be completely resected. For GDCs protruding into the stomach cavity, endoscopic surgery such as ESD can be adopted to remove the lesion. Endoscopic full-thickness resection (EFTR) may become an option for larger GDCs in the future. For extraluminal GDC, laparoscopic surgery is currently preferred. In this review, we summarized the structural and histopathological characteristics of GDCs and various treatment therapies, in order to provide experience and reference for the diagnosis and treatment of GDCs in the future.