（1）X線検査

Diagnostic Imaging for Early Gastric Cancer─Methods and Accuracy of Screening by Radiography

要旨　2001年に発行された新・胃X線撮影法（間接・直接）ガイドラインに準じて，現在対策型検診で行われている間接X線について高濃度低粘性バリウムを使用した8枚法と，人間ドックなどの任意型検診で行われている直接X線のスクリーニング検査方法をそれぞれ概説する．X線の精度は画像精度と診断精度の両面から考慮する必要があり，画像精度については統一された撮影法と画像評価法の確立が必要であり，診断精度については死亡率を指標とした多施設による検討と同時に正確な癌登録をもとにした後ろ向き研究や，偽陰性例を中心としたX線診断精度の研究，検討を行う必要がある．

　In accordance with the new guidelines for roentgenogram examinations published in 2001, we give an outline of two types of examinations. Firstly, fluorography for population-based screening based on eight images and using dense, non-viscous barium. Secondly, film radiography for diagnosis in personal random health checks.

　Concerning radiogram examination accuracy, it should be noted that this involves both image accuracy and diagnostic accuracy. For image accuracy, there is an immediate need for standardization of both radiographic method and of the way the data it presents is estimated. 　For diagnostic accuracy, there is a need to make multicenter investigations based on mortality rate as an index. In addition to this, retrospective studies should be carried out on the cancer registration of the cases encountered and the diagnostic accuracy of the cases, taking into consideration the false negative diagnoses that were made.