LAUSR

Submucosal tunneling endoscopic resection (STER) for the treatment of upper gastrointestinal submucosal tumors originating from the muscularis propria was first introduced by Xu et al. [1] in 2012. It has been demonstrated to be safe and effective for treating small (<3.5 cm) esophageal leiomyoma. However, sometimes the esophageal leiomyoma may be a giant mass and protrude into the mediastinum. It is uncertain whether STER can be used to resect the mass in the mediastinum. In this case, we successfully carried out STER in a patient with giant leiomyoma protruding into the mediastinum.