ⓔコラム11-4-12 除菌後胃癌の臨床病理学的特徴
除菌後胃癌とH. pylori陽性胃癌では，臨床病理学的特性が大きく異なる．
除菌後胃癌においては，腫瘍径が小さい，陥凹型が多い，細胞増殖の指標となるKi–67 indexが低い，胃型粘液形質の増加，腸上皮化抑制が指摘されている3,4)．
特に除菌後胃癌においては内視鏡的に表層形態が判別し難くなることが指摘されている5,6)．除菌後胃癌では組織学的に表層を低異型度上皮が多い，内視鏡的には拡大NBIにより不整の乏しい胃炎様所見 “gastritis–like appearance”の存在が指摘され，注意深い内視鏡スクリーニングが必要である7–9)．
〔兒玉雅明・村上和成〕
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