Application of Underwater Endoscopic Submucosal Tunnel Dissection Technique in the Treatment of Early Esophageal Cancer: A Case Report

Background Early esophageal cancer requires precise and minimally invasive treatment strategies. Endoscopic submucosal dissection (ESD) and endoscopic submucosal tunnel dissection (ESTD) have demonstrated high efficacy in en bloc resection. The underwater ESTD (U-ESTD) technique, which utilizes water infusion instead of submucosal injection, has emerged as a promising alternative for improving visualization, reducing thermal injury, and maintaining a stable surgical field. Methods We report a case of a 51-year-old male with early-stage squamous cell carcinoma in the cervical and mid-esophagus. The patient underwent ESD for the cervical lesion and U-ESTD for the mid-esophageal lesion. The underwater technique provided superior visualization and a protective submucosal cushion, enabling precise dissection while minimizing perforation and bleeding risks. The histopathological examination confirmed high-grade epithelial dysplasia with negative deep margins. No post-procedural complications were observed, and follow-up endoscopy at three months demonstrated complete mucosal healing. Results The histopathological examination confirmed high-grade epithelial dysplasia with negative deep margins. No post-procedural complications were observed, and follow-up endoscopy at three months demonstrated complete mucosal healing. Conclusion U-ESTD is a feasible, safe, and effective technique for the treatment of early esophageal cancer. By integrating water infusion and traction techniques, U-ESTD optimizes lesion resection while minimizing complications. This case highlights the potential of U-ESTD as an advanced therapeutic approach in minimally invasive endoscopic surgery.