低異型度分化型胃癌のX線像の検討

The Radiographic Study of Low-Grade Gastric Cancer

要旨　低異型度分化型胃癌のX線像の特徴を明確にするために，当センターで経験した115例を対象として，粘液形質と肉眼型に分類し検討した．粘液形質は，胃型30例，混合型24例，腸型61例であった．（1）腫瘍径：胃型と混合型は30mm以上（72％）が，腸型は30mm以下（85％）が多かった．（2）肉眼型：胃型と混合型はIIb進展を伴う病変（29.6％）が多く，腸型は隆起型（67％）が多かった．（3）X線所見：隆起型では，胃型と混合型は，胃小区に類似した大小不同の不規則な配列をもつ顆粒状隆起で，境界不明瞭であった．一方，腸型は，腸上皮化生に類似し，線状陰影で仕切られた比較的均一で平滑な顆粒状隆起を呈し，境界明瞭であった．陥凹型では，胃型と混合型は，陥凹辺縁が微細な鋸歯状で，不規則な線状陰影や微細な顆粒を伴っていた．IIb進展部は，空気量やバリウム量などの撮影条件を変えて詳細に撮影すると，微細顆粒状陰影やバリウムの付着差が生じ，境界診断が可能であった．腸型は，陥凹面が平滑で，微細顆粒状のなだらかな辺縁隆起を伴っていた．（4）深達度：腸型と混合型は全例M癌，胃型はリンパ節転移陽性のSM2癌を2例認めた．以上から，胃型は，境界不明瞭で存在診断や範囲診断が難しく，低異型度癌と言えども悪性度の高い病変があり，注意が必要である．

　Recently, low-grade gastric cancer has been identified, so we need more exact diagnosis than before. For this reason, we have analyzed the radiography of low-grade cancer by classification of mucin phenotype. In gastric mucin phenotype and mixed mucin phenotype, the major colors of cancer areas are red and colors similar to the surrounding nomal area. In intestinal mucin phenotype, the major color is discoloration. In size, gastric mucin phenotypes are big and intestinal mucin phenotypes are small, less than 3cm long. Macroscopically, most gastric mucin phenotypes and mixed mucin phenotypes are the flat type and most intestinal mucin phenotypes are the elevated type. Radiographically, gastric mucin phenotypes presented granules with irregular shapes, and intestinal mucin phenotypes presented circular smooth granules. In X-ray examination, when we examined lesions under changing conditions such as amount of air and barium, barium adhered differently and made it possible for us to make judgments.