Submucosal Tunnelling Endoscopic Resection for Oesophageal Duplication Cyst: A Case Report.

Oesophageal duplication cysts are rare congenital anomalies of the foregut. Although frequently asymptomatic, these cysts may cause symptoms like dysphagia, chest pain, or respiratory issues if they grow large enough to compress adjacent structures. Endoscopic ultrasound is essential for accurate diagnosis, and though surgical resection remains the conventional therapy for symptomatic cysts, advanced endoscopic techniques are increasingly recognized as effective, less invasive alternatives. We report the case of a 40-year-old man who presented with dysphagia to solids for 3 months. Upper gastrointestinal endoscopy revealed a large submucosal lesion with fluctuation sign positive, and EUS demonstrated a 4×6.5 cm anechoic to hypoechoic lesion arising above the muscularis propria, likely an oesophageal duplication cyst. The patient underwent successful submucosal tunnelling endoscopic resection (STER) of a cystic lesion under general anaesthesia. This case highlights the feasibility and efficacy of STER as a minimally invasive treatment option for oesophageal duplication cysts.