linitis plastica型胃癌初期病変の内視鏡診断

Endoscopic Study of the Early Phase in Linitis Plastica Type Gastric Cancer

要旨　逆追跡されたlinitis plastica型胃癌の初期病変は微小なものだけではなく，相当の大きさの例もみられる．linitis plastica型胃癌の初期像の診断精度を向上させる目的で，非萎縮帯に存在した未分化型SM・MP癌46例の内視鏡的所見を検討した．①粘膜下組織の癌浸潤範囲が粘膜内進展範囲より広く，②粘膜下組織の線維化組織を越えて癌が浸潤する病巣を初期病変であるpre-linitis plasticaとすると10例が該当した．pre-linitis plastica癌の内視鏡的特徴として，癌巣中央陥凹面の白苔，癌巣周囲隆起，皺襞集中を認めることが多かった．これに対して小範囲浸潤例は白苔，周辺隆起が少なく．充実型低分化腺癌例は白苔，ひだ集中が少なく，鑑別が可能ではないかと思われた．しかし，粘膜下層に大量浸潤した例では白苔，周辺隆起，ひだ集中が観察されることが多く，pre-linitis plasticaとの鑑別が難しいものが含まれると考えられた．

　In a retrospective survey of the patients diagnosed as having linitis plastica type gastric cancer, it was found that the lesions in the early phase were not always small, but sometimes might be considerable in size. In order to raise the diagnostic accuracy in the early phase of linitis plastica type, we investigated endoscopic findings of 46 undifferentiated carcinoma lesions which were localized in the non-atrophic gastric mucosal zone and had invaded the submucosa or muscular is propria. Pre-linitis plastica types were defined as lesions in which cancer cells extended more beyond fibrous tissue in the submucosa than in the mucosa. In 10 pre-linitis plastica type lesions, the endoscopic examination frequently showed slough, surrounding protrusion and fold conversion. Since slough and surrounding protrusion were few in 18 small invasive type lesions and slough and fold conversion were few in 11 solid type lesions, we suspected that it was possible to distinguish pre-linitis plastica type into these two types. However, 5 massive invasion type lesions resembled pre-linitis plastica type in endoscopic features, so it would be not easy to distinguish the two types.