早期胃癌治療のための精密検査―浸潤範囲を読む

Detailed X-ray Examination of Early Gastric Cancer for Identifying the Extent of Invasion

要旨　①早期胃癌の治療法の選択に当たり，浸潤範囲の診断が特に重要となる場合について，主にX線診断の立場から検討した．①噴門部および胃体上部の癌では，下部食道への浸潤の有無とその範囲の証明が不可欠であり，撮影法としては右側臥位ないし半臥位第2斜位と立位正面ないし第1斜位の二重造影像が有効である．①胃体部の癌はEGJからの距離によって術式が全摘か部分切除かが決定され，それによって術後の quality of life が大きく影響される．したがって，胃体部では病変の口側境界の診断は特に重要となるが，その証明には背臥位二重造影像が優れており，EGJからの距離の計測には立位の胃上部二重造影像が必要である．①内視鏡的粘膜切除の適応を決める際に未分化型癌，特にその隆起型病変は周囲粘膜への浸潤に注意する必要がある．

　The extent of invasion of early gastric cancer may be crucial for selecting the treatment of choice. We analyzed it from the x-ray diagnostic points of view. For gastric cancer being located in the cardiac region and the upper body, it is very important to diagnose their extent of invasion, especially to the lower esophagus. The useful projections and positions of double contrast study to identify the extent of invasion are the left anterior oblique view of the lying on the right side or the semi-recumbent position, and the frontal or right anterior oblique view of the upright position. For gastric cancers being located in the gastric body, the selection of surgical method, whether a total or partial gastrectomy, is based on the distance between the edge of invasion and the EGJ. This choice would affect the patients' quality of life. Therefore, the diagnosis of the extent of invasion, particularly in oral edge of the lesion in the gastric body is important. Double contrast study in the supine position is useful to determine the invasivty, but that in the upright position is necessary to measure a distance from the EGJ. To evaluate an indication for endoscopic mucosectomy, it is important to diagnose the invasivity to the surrounding mucosa of the undifferentiated type cancer, in particular, with the elevated lesion.