A Study to Evaluate the Esophageal Stenosis Inhibition Effects of CLS2702C/CLS2702D After Endoscopic Submucosal Dissection (ESD) in Patients With Superficial Esophageal Cancer in the Steroid Administration Risk Group

"CLS2702C (cell sheet) will be transplanted to the wound site using CLS2702D (transplantation device) (screening period, 1 month \[4 weeks\]; cell sheet culture period, 0.5 month; transplantation and assessment period, 6 months \[24 weeks\]); follow-up period, 6 months \[24 weeks\]) Other Names: •Human (autologous) oral mucosal cell sheet~•Transplantation device"