胃噴門部癌の発育進展の特徴

Growth and Spread Pattern of Cardiac Cancers

要旨　胃噴門部癌157例を用いてその発育進展を検討した．最大径，肉眼型，組織型，深達度，組織学的所見などを解析した．最大径2cm未満からsm癌がみられ，3cm未満ではss癌，4cm未満でse癌が出現した．組織型は早期癌では高分化型が多く，進行癌では低分化型が多かった．低分化型早期癌は極めて少なかった．隆起型では高分化型が主で，Ⅱc型はいずれの組織型ともみられたが，低分化型Ⅱcの多くは早期癌類似進行癌であった．解析の結果噴門部癌は，①早期癌と進行癌での低分化型癌の比率の逆転が他部位より顕著にみられ，②複合型癌が多く，③小型の進行癌が多く，④細胞異型が高い，という特徴がみられた．噴門部癌の多くは高分化型癌として発生するが異型度が高く，早期から低分化成分が出現して深部へ浸潤し，最終的には低分化型進行癌を形成するという発育進展形式が推論された．

　We studied cardiac cancers and their progression by closely examining 157 cases. Major size, shape, depth of invasion and histology were studied.

　By the time they were 2 cm in size their invasion depth was as far as the sm-layer. This depth had increased to as far as the ss by the time they were 3 cm in size, and to se by the time they were 4 cm in size. Histologically, well-differentiated type was dominant among early cancers. On the other hand, poorly-differentiated type was dominant among advanced cancers. Protruded lesions were mostly well-differentiated ones. Depressed lesions showed features of both histological types, but most of the poorly differentiated type Ⅱc lesions were advanced cancers.

　We concluded that early and advanced lesions of cardiac cancer show a certain disassociation from histological types. Their histology is mixed, and even small size tumors may invade the cardiac wall. Cytologically, their appearances are highly atypical.

　We infer that they mostly originate as well-differentiated and highly atypical tumors, but they progress with histological transformation and finally form poorly-differentiated advanced carcers.