Narrow-band imaging with magnification in Barrett’s esophagus: validation of a simplified grading system of mucosal morphology patterns against histology

BACKGROUND AND STUDY AIMS Validation of a simplified classification of mucosal morphology in prediction of histology in Barrett's esophagus using narrow-band imaging with magnification (NBI-Z) and assessing its reproducibility by endoscopists experienced in the use of NBI (NBI-experts) and by endoscopists who were new to NBI (non-NBI-experts). PATIENTS AND METHODS In a prospective cohort study of 109 patients with Barrett's esophagus at a single tertiary referral center, mucosal patterns visualized in Barrett's esophagus on NBI-Z were classified into four easily distinguishable types: A, round pits with regular microvasculature; B, villous/ridge pits with regular microvasculature; C, absent pits with regular microvasculature; D, distorted pits with irregular microvasculature. The NBI-Z grading was compared with the final histopathological diagnosis, and positive (PPV) and negative predictive values (NPV) were calculated. The reproducibility of the grading was then assessed by NBI-expert and non-NBI-expert endoscopists, and interobserver and intraobserver agreement were calculated using kappa statistics. RESULTS Per-biopsy analysis: In 903 out of 1021 distinct areas (87.9%) the NBI-Z grading corresponded to the histological diagnosis. Per-patient analysis: The PPV and NPV for type A pattern (columnar mucosa without intestinal metaplasia) were 100% and 97% respectively; for types B and C (intestinal metaplasia) they were 88% and 91% respectively, and for type D (high-grade dysplasia) 81% and 99% respectively. Inter- and intraobserver agreement: The mean kappa values in assessing the various patterns were 0.71 and 0.87 in the non-expert group; 0.78 and 0.91 in the expert group. CONCLUSIONS This study has validated a simplified classification of the various morphologic patterns visualized in Barrett's esophagus and confirmed its reproducibility when used by NBI-expert and non-NBI-expert endoscopists.

[1]  Kohzoh Imai,et al.  Usefulness of narrow-band imaging endoscopy for diagnosis of Barrett’s esophagus , 2003, Journal of Gastroenterology.

[2]  K. Yao,et al.  Novel endoscopic observation in Barrett’s oesophagus using high resolution magnification endoscopy and narrow band imaging , 2007, Alimentary pharmacology & therapeutics.

[3]  J. R. Landis,et al.  The measurement of observer agreement for categorical data. , 1977, Biometrics.

[4]  R. Playford.  New British Society of Gastroenterology (BSG) guidelines for the diagnosis and management of Barrett’s oesophagus , 2006, Gut.

[5]  J. Goldblum,et al.  The diagnosis of low-grade dysplasia in Barrett's esophagus and its implications for disease progression , 2000, American Journal of Gastroenterology.

[6]  Michael Vieth,et al.  The development and validation of an endoscopic grading system for Barrett's esophagus: the Prague C & M criteria. , 2006, Gastroenterology.

[7]  J. Fraumeni,et al.  Changing patterns in the incidence of esophageal and gastric carcinoma in the United States , 1998, Cancer.

[8]  M. Dixon.  Gastrointestinal epithelial neoplasia: Vienna revisited , 2002, Gut.

[9]  A. Bansal,et al.  The utility of a novel narrow band imaging endoscopy system in patients with Barrett's esophagus. , 2005, Gastrointestinal endoscopy.

[10]  J. Olliver,et al.  Chromoendoscopy with methylene blue and associated DNA damage in Barrett's oesophagus , 2003, The Lancet.

[11]  P. Moayyedi,et al.  Esophageal adenocarcinoma arising from Barrett's metaplasia has regional variations in the west. , 2002, Gastroenterology.

[12]  P. Fockens,et al.  Detection and classification of the mucosal and vascular patterns (mucosal morphology) in Barrett's esophagus by using narrow band imaging. , 2006, Gastrointestinal endoscopy.

[13]  A. Cameron,et al.  Barrett's esophagus, high-grade dysplasia, and early adenocarcinoma: a pathological study. , 1997, The American journal of gastroenterology.

[14]  P. Enzinger,et al.  Esophageal cancer. , 2003, The New England journal of medicine.

[15]  N. Powe,et al.  Methylene blue-directed biopsies improve detection of intestinal metaplasia and dysplasia in Barrett's esophagus. , 2000, Gastrointestinal endoscopy.

[16]  Masahiro Yamaguchi,et al.  Appearance of enhanced tissue features in narrow-band endoscopic imaging. , 2004, Journal of biomedical optics.

[17]  C. Hawkey,et al.  Acetic acid‐enhanced magnification endoscopy in the diagnosis of specialized intestinal metaplasia, dysplasia and early cancer in Barrett's oesophagus , 2006, Alimentary pharmacology & therapeutics.

[18]  F. Ellis,et al.  Endoscopic surveillance of Barrett's esophagus. Does it help? , 1993, The Journal of thoracic and cardiovascular surgery.

[19]  R. Sampliner,et al.  Updated guidelines for the diagnosis, surveillance, and therapy of Barrett's esophagus , 2002, American Journal of Gastroenterology.

[20]  J Van Dam.  Novel methods of enhanced endoscopic imaging. , 2003 .

[21]  A. Bhattacharyya,et al.  Magnification chromoendoscopy for the detection of intestinal metaplasia and dysplasia in Barrett’s oesophagus , 2003, Gut.