[701] Evaluation of Esophageal Biopsies for Squamous Intraepithelial Neoplasia: Differences between Japan and the West.

Michio Shimizu, Junko Aida, Ian S Brown, Joel K Greenson, Anne Jouret-Mourin, Hiroshi Kawachi, Jochen K Lennerz, Koji Nagata, Kaiyo Takubo, Michael Vieth, Gregory Y Lauwers. Saitama Medical University, International Medical Center, Hidaka, Japan; Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Japan; Sullivan Nicolaides Pathology, Brisbane, QLD, Australia; University of Michigan, Ann Arbor; Universite Catholique de Louvain, Brussels, Belgium; Tokyo Medical and Dental University, Bunkyo-ku, Japan; Massachusetts General Hospital, Boston; Klinikum Bayreuth, Bayreuth, Germany

Background: Compared to dysplasia in Barrett esophagus, limited attention is given to squamous intraepithelial neoplasia (IEN). Also, variation in the evaluation of early squamous neoplasms between Japanese and Western observers has been noted. Our aim was to test the Western and Japanese's evaluations of esophageal squamous neoplasia by comparing grading between these two groups.
Design: Digitalized H&E slides from 50 esophageal biopsies covering all recognized grades from benign to malignant lesions were circulated among 5 Japanese and 5 Western pathologists. The participants classified the lesions as: negative or indefinite for neoplasia, low- or high-grade IEN or squamous cell carcinoma (including probably invasive). Consensus diagnoses were defined as the opinion of the majority and interobserver variability was assessed by kappa statistics.
Results: A majority diagnosis (in which more than 6 agreed) was reached in 21 cases (42%). Seven more cases had a majority diagnosis when high-grade IEN and squamous cell carcinoma where combined. A unanimous diagnosis was reached in only 5 cases (all benign). Within the Japanese group, the overall level of agreement was moderate to almost perfect (kappa:0.54 to 0.9). The intragroup agreement among Western pathologists was moderate to good (kappa:0.5 to 0.79). The intergroup agreement between Japanese and Western observers was moderate to excellent (kappa:0.41 to 0.81) Eight cases diagnosed as low grade IEN by a majority of Western pathologists were diagnosed as at least high grade IEN by a majority of Japanese observers. The Japanese pathologists as a group diagnosed 45% of cases a category higher than Western pathologists. After excluding the 5 cases with perfect agreement, the average increase in consensus diagnosis between Japanese and Western pathologists equaled one full grade higher.
Conclusions: Japanese pathologists tend to diagnose esophageal squamous IEN more aggressively than Western pathologists. The interobserver variability is caused by the lack of universally accepted criteria. An international effort is needed to harmonize the criteria and analyze possible therapeutic implications.
Category: Gastrointestinal

Monday, February 28, 2011 1:00 PM

Poster Session II # 82, Monday Afternoon

 

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