胃生検Group分類の歴史と問題点―Vienna分類との関係も含めて

Group Classification for Interpretation of Gastric Biopsy Specimens―Its History and Intrinsic Problems (Including Its Relation to Vienna Classification)

要旨　胃癌取扱い規約による現行のGroup分類（第11版，1985年にて改訂）の成立過程，およびその問題点を述べた．また，Vienna Consensus Classification（2000年）の成立過程，Group分類との対比，その問題点にも触れた．日本におけるGroup分類を，Vienna分類（Category分類）の長所を取り入れて，特にGroup IIをindefinite for dysplasia/neoplasiaとするよう，改訂すべきとの声があるが，現行のGroup分類は18年以上の長さにわたって，それなりの妥当性をもって広く用いられている．改訂は慎重であらねばならない．

　The Group Classification for interpretation of gastric biopsy specimens was first presented in 1971 by the JRSGC (Japanese Research Society for Gastric Cancer), in order to express simply the histological changes occurring in the gastric epithelium and to standardize the histological criteria for gastric carcinoma. It was revised in 1985 with an expanded concept of Group III and has been widely accepted in Japan since then. In this paper, the process of the revision and some intrinsic problems of the classification were mentioned. One of the big problems is that the Group III contains two elements,“adenoma” and “indefinite for dysplasia/neoplasia” without any designation (Group Classification, however, recommends that the contents of the change should be described together with the Group Number). Further, the purpose, advantages and disadvantages involved in the use of the Vienna Consensus Classification (Category Classification, 2000) were explained together with its relation to the Group Classification. It is advocated that the Group Classification should be renovated by taking the advantages of the Vienna Classification (e.g. setting of Category II as “indefinite for dysplasia/neoplasia”) into consideration. However, since the Group Classification is very popular in Japan and, since unnecessary confusion should be avoided, the renovation of the Group Classification, if made, should be carried out with care.

　1) Department of Pathology, The Cancer Institute of Japanese Foundation for Cancer Research, Tokyo