We herein report a rare case of early oesophageal cancer combined with an oesophageal muscularis propria defect discovered under endoscopic submucosal dissection. The surgeon did not damage the muscularis propria during endoscopic resection; however, we observed the mediastinal cavity as well as the later occurrence of subcutaneous emphysema. Consequently, the patient was considered to have a muscularis propria defect. This phenomenon has not been reported in the literature to date.
Keywords: Early oesophageal cancer; case report; endoscopic piecemeal mucosal resection; endoscopic submucosal dissection; oesophageal metal-covered stent; oesophageal muscularis propria defect.