Endoscopic Submucosal Dissection for Superficial Esophageal Neoplasm: A Growing Body of Evidence.

Recent advances in endoscopic techniques, including magnifying endoscopy and image-enhanced endoscopy, have increased the detection rate of early-stage esophageal squamous cell neoplasm (ESCN). Treatment options for superficial ESCN have expanded, with endoscopic resection considered the standard treatment. Several studies have reported favorable clinical outcomes of endoscopic resection for superficial ESCN that are comparable to those of esophagectomy, with minimal invasiveness. Endoscopic treatment for ESCN includes endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD), with ESD has enabled en bloc resection for large tumors. ESD for esophageal neoplasm is technically difficult and requires advanced endoscopic skills because of the narrow space and peristalsis of the esophagus. This technical difficulty may result in incomplete tumor resection, increasing the likelihood of recurrence. Different risk factors associated with local recurrence have been reported, including the size of lesion, piecemeal resection, and EMR as compared with ESD. Although ESD enabled to overcome these factors, effort should be made to achieve en bloc curative resection of esophageal neoplasm. In this issue of Clinical Endoscopy, Park et al. reported the clinical outcomes of ESD for superficial ESCN. ESD was performed in 32 patients with 36 lesions, and the en bloc resection and R0 resection rates were 97.2% (35/36) and 91.7% (33/36), respectively. There was no case of local recurrence or distant recurrence during a median follow-up period of 27 months after curative resection. These results are consistent with those of previous reports that showed favorable clinical outcomes after ESD. ESD is currently indicated for lesions that do not exceed the mucosal layer (T1a), particularly for those confined to the lamina propria mucosa, because of their negligible risk of lymph node metastasis. Although some reports showed favorable outcomes, ESD for tumors invading the muscularis mucosa or the submucosa (T1b) remains controversial and is considered relative to the indications. There have been attempts to expand the indications of ESD for superficial ESCN. However, the long-term risk of metastasis after endoscopic resection was associated with the tumor invasion depth, and the 5-year overall survival rates of patients with tumors invading the muscularis mucosa or submucosa were significantly lower than those of patients with tumors confined to the lamina propria mucosa in a previous report. More evidence regarding the risk of lymph node and distant metastasis in patients with tumors invading the muscularis mucosa or submucosa is warranted to justify the use of ESD for these lesions. In the present study, 33.3% (12/36) of enrolled cases did not Received: March 3, 2016 Revised: March 5, 2016 Accepted: March 6, 2016 Correspondence: Hwoon-Yong Jung, Department of Gastroenterology, Asan Digestive Disease Research Institute, Asan Medical Center, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505, Korea Tel: +82-2-3010-3197, Fax: +82-2-476-0824, E-mail: [email protected]