胃癌の組織型の変化―分化型癌から未分化型癌へ

Change of Histological Type of Gastric Carcinoma: From Differentiated Carcinoma to Undifferentiated Carcinoma

要旨　癌の進展に伴う組織型の変化の詳細を検討するために246例の粘膜下深達癌を検討したところ，以下の結果を得た．①粘膜内と粘膜下層で組織型の変化した症例および分化型と未分化型の混合型の群は，組織型の変化しない純粋の分化型と純粋の未分化型との中間的な臨床病理学的な特徴を有し，特殊な癌型であった．②ある種の分化型が混合型に変化し，更に未分化型に変化する．③分化型の形態変化は，粘膜内，あるいは粘膜内から粘膜下層に深達する際に起こり，更に粘膜下層では浅部から中層に至る段階で分化型から混合型に，中層から深層に至る段階で混合型から未分化型に変化する．以上から，進行するにつれて未分化型癌の割合が増加するのは，ある種の分化型癌が未分化型に変化するために起こると結論した．

　Two hundred and forty six cases of submucosal invasive gastric carcinoma were examined to discover the change of histological type as the carcinoma develops. Histological type of carcinoma was divided into three types; pure differentiated-type, pure undifferentiated-type and mixed-type. Mixed-type means a type somewhere between differentiated and undifferentiated.

　Clinicopathologically, the mixed-type group and the group whose histological type was different in the submucosa from where it was in the mucosa were an intermediate group between the pure well-differentiated-type group and pure undifferentiated-type group.

　The histological cahnge of differentiated-type took place in the mucosa and the submucosa. In the mucosa, the differentiated-type changed into mixed-type with increasing diameter. In the superficial zone of submucosa, differentiated-type changed into the mixed-type and the mixed-type changed into the undifferentiated-type in the deep zone of the submucosa.

　It was concluded that a differentiated-type carcinoma changed into an undifferentiated-type carcinoma, passing through a mixed-type stage, and eventually to an undifferentiated-type carcinoma. The ratio of undifferentiated-type to differentiated-type carcinoma increased as the development of the carcinoma increased.