微小胃癌A.H染色による病理学的検索の1方法

A Method for Pathological Study of Gastric Microcarcinoma: Alcian blue-Hematoxylin method

　早期胃癌診断の進歩により微小癌（最大径0.5cm）の発見も可能になったといわれる．しかし切除胃を手に取って調べてもわからない癌腫があり，かなり大きなものでも組織で初めて診断されるものなどがある．現実には容易に診断できるものではない．組織診断をあてにして全縦割半連続標本を作成しても約0.4cmのブロックの間に癌腫が逃げることもあって，盲目的検索を行うことにも問題がある．

　微小癌の診断能を向上するには，まず癌腫の存在を肉眼でとらえ，疑わしい病変も含めて組織判定することが大切で，つぎにその性状を知って診断と治療に役立てる手続きが必要であろうと考えられる．そこで微小癌発見の1方法として，切除胃をそのままA・H法¹⁾で染色し，肉眼で粘膜表面から検索することを試みた．A・H法は胃粘膜の微細変化を色調と形態に現わし，現状では腸上皮化生，異型病変，とくに癌腫の表面形態と浸潤範囲（酵素発色法ではわかりにくい）の観察に最適な方法と思われる．今回はA・H法で発見した微小癌を中心に年齢，癌腫の色調，染色性，形態，病巣数，占居部位，大きさと組織型などを検討し，粘膜表面観察の限界などについて述べたい．

　When a resected gastric specimen fixed with 10% Formalin solution is stained with Alcian blue-Hematoxylin (A. H method), one can Observe minutely on the mucosal surface such changes as intestinal metaplasia and cancer. The normal gastric mucosa is stained red brown, showing characteristic rnucosal patterns, that is, gastric areas and forveolar and sulcate patterns. Mucosa with complete intestinal metaplasia is stained blue, varying in its depth according to the density of goblet cells. Atypical epithelium and cancer cells, more resistant to staining, remains pale. Using this method, we were able to detect 200 cases (251 lesions) of early cancer out of 398 resected stomachs. In early cancer the gastric mucosa looked pale in 89.2 per cent. It stained deeply in 4.4 per cent (11/251) and intermediately in 6.4 per cent (16/251). In microcarcinoma less than 0.5cm in the greatest diameter clinical diagnosis was made in 3 lesions, diagnosis by A. H method in 13 and histologic diagnosis in 24. For the diagnosis of microcarcinoma as judged from changes on the mucosa it is important to look for changes in shades, dissolution or disappearance of the mucosal patterns, findings of infiltration at the level of individual pit. Microcarcinoma can be detected satisfactorily by observing with a loupe. However, microcarcinoma must proliferate to about 0.4 cm in the greatest diameter before its characteristics appearon the mucosal surface. Macroscopically, the majority of microcarcinoma was Ⅱc, followed in frequency by Ⅱa and Ⅱa+Ⅱc types. We believe A. H method is an effective procedure in the detection of microcarcinoma both clinically and pathologically because even small changes of the gastric mucosa can hardly by missed, and the whole of the resected stomach can be well observed.