Long-term prognosis and DNA damage status after oral mucosal epithelial cell sheet transplantation following esophageal endoscopic submucosal dissection for squamous cell carcinoma: A case series.

Autologous oral mucosal epithelial cell sheet (AOMECS) transplantation has recently been applied in human patients to prevent postprocedural stenosis following endoscopic submucosal dissection (ESD) for esophageal squamous cell carcinoma. However, the long-term safety of AOMECS transplantation remains unclear. We evaluated the long-term outcomes of 10 patients who participated in a clinical trial of AOMECS transplantation after esophageal ESD. Additionally, we assessed the local DNA damage response in the esophageal epithelium using p53 binding protein 1 (53BP1) immunofluorescence in post-AOMECS biopsy specimens. The median follow-up period was 118.5 months (range: 46-130 months). Two patients developed primary esophageal cancer near the AOMECS site and successfully underwent additional ESD. One patient developed lymph node metastasis and underwent chemotherapy. None of the patients died from the original disease, although one patient died from unrelated causes. The rate of abnormal 53BP1 nuclear foci, indicative of increased genome instability, increased with the progression of neoplasia in patients post AOMECS. Our case series suggests that AOMECS transplantation provides an acceptable long-term prognosis and 53BP1 foci may serve as a useful marker for assessing DNA instability in the post-AOMECS esophageal epithelium.