胃癌の深達度診断—X線検査

Diagnosis of the Invasion Depth for Gastric Cancer by Gastric X-ray Examination

要旨●胃癌の深達度診断は肉眼型や組織型から行うことが基本であるが，0-IIc型や0-III型などの陥凹型は早期胃癌形態を呈する進行癌の場合がある．X線造影検査は，粘膜下層以深に浸潤した癌による胃壁の変化を評価するため，深達度診断に有用である．粘膜下層以深への浸潤所見として，正面像では胃ひだや陥凹の所見，例えば胃ひだの太まりや収束像，陥凹の台状挙上，陥凹内隆起などが重要である．側面像では側面変形を評価するが，部位により所見に強弱が出る可能性がある．特に粘膜下層浸潤が疑われる陥凹型胃癌に対して，X線造影検査を積極的に行い，正面像および側面像にて，粘膜下層以深への浸潤所見を評価し，深達度診断を行うことが重要である．

　The diagnosis of the invasion depth of gastric cancer is based on the gross and histological types ; however, a type 0-IIc or 0-III lesion has the possibility of developing into advanced gastric cancer. Gastric X-ray examination evaluates the changes in the gastric wall caused by the gastric cancer, and hence facilitates the diagnosis of the invasion depth of the gastric cancer that has invaded the submucosal layer or has gone deeper. The most significant findings of submucosal invasion are the folds and depressions, particularly the convergence of the gastric folds, elevation of the depressed lesion, and elevation of the intradepressions, that are visible on the frontal view. The lateral view evaluates the lateral deformity, but the intensity of the findings can be more or less, depending on the site. Gastric X-ray examinations are particularly important in case of depressed-type lesions with suspected submucosal invasion since they can help diagnose the depth and extent of invasion through the evaluation of the findings of submucosal invasion from the frontal and lateral views.