SLND Versus Non-Dissection Following ESD for T1a Stage Esophageal Squamous Cell Carcinoma

Participants will be evaluated for inclusion criteria and exclusion criteria, and then sign informal consent if desired. Participants will be randomly assigned to the intervention according to a prepared random tables. Participants in the SLND group will receive Endoscopic Submucosal Dissection with systematically mediastinal lymph node dissection

Participants will be evaluated for inclusion criteria and exclusion criteria, and then sign informal consent if desired. Participants will be randomly assigned to the intervention according to a prepare random tables. Participants in the non-SLND group will just receive Endoscopic Submucosal Dissection treatment, not undergo Systematically mediastinal Lymph Node Dissection.