Esophageal Cancer Secondary to Achalasia: A Case Series Study.

Introduction: Achalasia is a primary motility disorder affecting the esophageal body and lower esophageal sphincter. Although the linkage between achalasia and elevated esophageal cancer risk is already known, the precise mechanisms remain poorly elucidated due to the disease's relative scarcity. We aim to summarize the clinical characteristics of esophageal cancer (EC) secondary to achalasia and improve the understanding of achalasia combined with EC and further reduce the risk of ECs. Case Presentations: Retrospective statistics were conducted on patients with ECs secondary to achalasia in our hospital from 2009 to 2023. We categorized all achalasia cases with their initial treatment and recorded subsequent interventions when the symptoms recurred. Additionally, we performed detailed analyses of both EC characteristics and therapeutic regimens. We present a case series comprised of 5 patients with achalasia who presented with EC. Three of the patients diagnosed with achalasia were treated by endoscopy or operation to improve symptoms. One patient was treated by pneumatic dilation. All were histologically diagnosed as squamous cell carcinoma. The validity period of endoscopic treatment has been lost in all patients. The erosions were all distributed over the thoracic esophagus. Conclusion: The high relative risk of ECs was demonstrated in achalasia patients, even in the treated achalasia patients. Therefore, surveillance endoscopy may be recommended regularly in the treated patients.