IntroductionWe reported the short-term outcomes of a regenerative medical treatment to prevent esophageal stricture after endoscopic submucosal dissection (ESD) using cultured tis oral mucosal epithelial cell sheets. This study investigated the long-term outcomes of this treatment. MethodsEpithelial cells, isolated from the patient's own oral mucosal tissue, were cultured for 16 days using temperature-responsive culture dishes. Then, the autologous cell sheets were endoscopically transplanted onto the bed of the esophageal ulcer after endoscopic mucosal resection (EMR) and ESD. Results of 10 patients who underwent endoscopic transplantation of oral mucosal epithelial cell sheets from April 2008 through February 2022 were recorded. We analyzed the outcome, the cause, and the endoscopic findings. ResultsThe median period of observation was 3761 days. No stricture was detected in any of the patients long-term. Two patients died because of pancreatic cancer and brainstem hemorrhage. One patient underwent chemo-radiotherapy for further treatment. The patients underwent surgery due to metastasis to the lymph nodes. Only the lymph nodes were dissected, and the esophagus remained intact. From the endoscopic findings: Melanosis was found at the transplanted site in a patient. Strong iodine staining was shown at the transplanted site in a patient. Transplantation of cultured oral mucosal epithelial cell sheets to prevent esophageal stricture has been proven to be a safe treatment. All patients showed no controlled esophageal stricture in the long term.