Histopathological Analysis of Esophageal Mucosa in Patients with Achalasia.

[BACKGROUND/AIMS] Achalasia is an esophageal motor disorder that leads to functional esophageal obstruction. Food stasis and bacterial fermentation can predispose an individual to esophageal mucosal inflammation, causing multifocal dysplasia and increasing the risk of developing esophageal squamous cell carcinoma. We aimed to evaluate esophageal mucosal alterations in achalasia patients and determine clinical factors associated with the histopathological findings.

[METHODS] From 2009 to 2013, we obtained endoscopic biopsies from the lower and middle esophagus of 22 patients with achalasia and 17 controls. Patients' clinical data and histological severity of esophagitis were retrospectively analyzed. Additionally, immunohistochemical staining for CD3, CD20, Ki-67, and p53 was conducted.

[RESULTS] The median age of achalasia patients was 49.5 years (range, 27 to 82 years), and there were nine males (40.9%). The median symptom duration was 5.8 years (range, 1 to 33.5 years), and 10 patients (45%) underwent previous treatment (nine, balloon dilation; one, botulinum toxin injection). Achalasia patients had significantly more severe esophagitis than did controls (p=0.001, lower esophagus; p=0.008, middle esophagus), and the number of CD3-positive lymphocytes exceeded that of CD20-positive lymphocytes (p<0.001). Achalasia patients also had a higher esophageal Ki-67 proliferation index (p=0.048). Although statistically nonsignificant, p53 expression was only observed in achalasia patients. There was no association between the histological severity of esophagitis and other clinicopathological findings.

[CONCLUSIONS] Achalasia patients showed significantly severe histological esophagitis and a high Ki-67 proliferation index, indicating an increased risk of neoplastic progression. Therefore, careful endoscopic inspection is necessary for the early detection of superficial neoplasia in these patients.