Validation of new Japanese classification system for esophageal achalasia.

BACKGROUND: The fourth edition of New Japanese classification system for esophageal achalasia was revised after a long interval of 30 years in 2012. In this new system, achalasia is morphologically classified into 3 types, based on its X-ray findings. However, the system has been limitedly used in Japan and has not been fully validated in terms of its predictive capability of postoperative outcomes. The purpose of this study was to clarify the validity of new Japanese classification system for esophageal achalasia, as an index of patient characteristics and as a predictor of operative and mid/long-term postoperative outcomes.

PATIENTS AND METHODS: Fifty-nine cases of achalasia underwent laparoscopic Heller-Dor surgery between 2005 and 2018. We evaluated retrospectively patient characteristics, intraoperative findings, esophageal manometry, 24-h pH monitoring and postoperative course.

RESULTS: There were 34 St and 25 Sg/aSg cases. Age of St group was lower than Sg group. Preoperative duration of disease of St group was shorter than Sg. There were no differences in the results of surgical outcomes and prognoses.

CONCLUSION: The new Japanese classification system may give additional insight and information in understanding epidemiology of esophageal achalasia; however, our study failed to demonstrate "inter-disease type" differences in surgical outcomes and prognoses.