Original article Evaluation of Barrett’s esophagus with CK7, CK20, p53, Ki67, and COX2 expressions using chromoendoscopical examination S ¸ . Çoban, 1 N. Örmeci, 2 B. Savas ¸, 3 F. Ekiz, 1 A. Ensari, 3 I. Kuzu, 3 M. Palabıyıkog ˘lu 2 1 Department of Gastroenterology, Diskapi Yildirim Beyazit Education and Research Hospital, Departments of 2 Gastroenterology and 3 Pathology, Ankara University Medical School, Ankara, Turkey [Correction added after online publication 5/22/12: title changed from ‘Evaluation of Barrett’s esophagus with CK7, CK20, p53, Ki67, and cyclooxygenase expressions using chromoendoscopical examination’] SUMMARY. Barrett’s esophagus (BE) is a complication of chronic gastroesophageal reflux disease and can be diagnosed when there is an endoscopically irregular Z-line and intestinal metaplasia (IM) in a biopsy obtained lower esophagus. It is still not clear whether IM in the gastric cardia or columnar mucosa without IM in the lower esophagus have any significance as BE, which is considered as preneoplastic. The aim of the study was to determine the immunohistochemical features of BE and columnar mucosa in the distal esophagus and also to evaluate the value of chromoendoscopy in the diagnosis of BE in a prospective manner. A total of 12 chromoendoscopic biopsies (six from normal-looking unstained esophagus and six from esophageal mucosa stained with methyl blue suspicious of BE) were taken from 111 cases who underwent endoscopy because of a variety of upper gastrointestinal symptoms. Immunohistochemical analysis was performed using CK7, CK20, p53, Ki67, and cyclooxygenase 2 (COX2). Of the 111 cases, 19 cases with carcinoma (nine adeno, six squamous, four undifferentiated carcinomas) and 17 cases with normal squamous epithelium were excluded, while 75 cases showing columnar epithelium, including 46 (61.3%) with IM and 29 (38,7%) without IM, were further evaluated immunohistochemically. CK7 was observed in surface, crypt, and glandular epithelium, whereas CK20 was expressed in surface and superficial crypt epithelium. No significant difference was observed between the Barrett and non-Barrett type of CK7/20 staining pattern (P > 0,05). Expression of p53 did not show any difference between BE and columnar mucosa without IM, whereas COX2 expression was significantly increased in BE (P < 0.05) in comparison with columnar mucosa without IM. Ki67 expression was significiantly higher both in upper and lower crypts in BE (P < 0.05). The present study showed that a Barrett pattern does not seem to exist; however, the analysis of COX2 expression and the Ki67 proliferation fraction by immunohistochemistry can be used to separate BE from non-Barrett’s metaplasia of the distal esophagus. In our point of view, the immunohistochemical detection of p53 expression in Barrett’s metaplasia stage is useless as a marker for early detection of high-risk patients. KEY WORDS: Barrett’s esophagus, chromoendoscopy, immunohistochemistry. INTRODUCTION Barrett’s esophagus (BE) is characterized by the replacement of the normal stratified squamous epi- thelium of the distal esophagus by columnar epithe- lium with specialized intestinal metaplasia containing goblet cells. 1 BE is a primarily caused by chronic gastroesophageal reflux disease and predisposes to the development of esophageal adenocarcinoma (EAC). 2 The prevalence of BE varied from 2.3–18% in patients with reflux symptoms to 1.2–6% without reflux symptoms. 3,4 Patients with EAC often have a poor prognosis with a high mortality rate, and the majority of patients often presents with an advanced and incu- rable stage of disease. It is known that EAC is a gradual process in which the accumulations of genetic changes result in disruption of different biologic process at the cellular level. This process progresses from intestinal metaplasia to low-grade dysplasia (LGD), high-grade dysplasia (HGD), and eventually EAC. 1 Address correspondence to: Associate Professor S ¸ ahin Çoban, MD, Department of Gastroenterology, Diskapi Yildirim Beyazit Education and Research Hospital, Ankara 06100, Turkey. Email: scoban72@yahoo.com [Correction added after online publication 5/22/12: Author was originally referred to as Professor] Diseases of the Esophagus (2013) 26, 189–196 DOI: 10.1111/j.1442-2050.2012.01352.x © 2012 Copyright the Authors Journal compilation © 2012, Wiley Periodicals, Inc. and the International Society for Diseases of the Esophagus 189 Downloaded from https://academic.oup.com/dote/article/26/2/189/2328992 by guest on 17 June 2022