Cell proliferation of squamous epithelium in gastro‐oesophageal reflux disease: correlations with clinical, endoscopic and morphological data

Abstract

The microscopic assessment of squamous epithelium lesions in gastro-oesophageal reflux disease (GERD) is subjective. The Ki67 nuclear antigen expressed by proliferating cells provides an objective measure of regeneration in the squamous epithelium. To evaluate Ki67 expression in GERD patients and controls, in comparison with histological lesions, pH-metry and endoscopic data. Eighty-seven patients with GERD symptoms and 20 symptom-free controls underwent endoscopy and 24-h pH monitoring. Oesophageal biopsies (4 cm, 2 cm and Z-line) were stained with Ki67/MIB-1 antibodies; the Ki67-positive nuclear area was assessed with an image analysis system and expressed as percentage of the whole epithelial area (Ki67-%). Ki67-% was significantly higher in 32 patients with erosive oesophagitis, 44 endoscopy-negative GERD and 11 patients with functional heartburn than in controls (P = 0.0001). Both controls and patients showed a progressive increase in Ki67-% from 4 cm to the Z-line (P < 0.0001). Ki67-% showed a significant correlation with other conventional histological lesions (P ranged between 0.0151 and <0.0001). Ki67 evaluation provides quantitative and objective data on squamous epithelium proliferative activity. This marker can be applied in the distinction of endoscopy-negative GERD from healthy controls.