Thoracoscopic esophagectomy for esophageal carcinoma after peroral endoscopic myotomy for esophageal achalasia: a case report

Background Esophageal achalasia causes dysphagia following impaired relaxation of the lower esophageal sphincter due to the degeneration of Auerbach’s plexus in the esophageal smooth muscle. Recently, peroral endoscopic myotomy (POEM) has become one of the preferred treatment options for esophageal achalasia. However, pathomorphological changes after POEM have not been well examined. Case presentation A 65-year-old man with a history of POEM for esophageal achalasia was diagnosed with clinical stage II (cT2-N0-M0) thoracic esophageal squamous cell carcinoma and was consequently treated with neoadjuvant chemotherapy followed by thoracoscopic esophagectomy. Intraoperatively, the esophagus appeared dilated, reflecting esophageal achalasia; however, fairly slight fibrous adhesions were observed between the esophagus and the pericardial surface despite previously performed POEM via an anterior incision. Histopathological examination revealed esophageal wall thickening, edema, and fibrosis extending from the lamina propria to the submucosa. Besides, the majority of the inner layer and some proportion of the outer layer of the muscularis propria were found to be missing or atrophic at the esophagogastric junction (EGJ). No ganglion cells could be detected at the Auerbach’s plexus. Conclusions The previous history of POEM did not affect circumferential mediastinal periesophageal dissection during thoracoscopic esophagectomy. Nevertheless, a large proportion of the inner layer of the muscularis propria at the EGJ level seemed to have become lost or atrophic because of the POEM procedure.