内視鏡による深達度診断のコツと診断困難な早期胃癌―症例を中心に

Diagnosis of the Depth of Cancer Invasion for Early Gastric Cancer

要旨　早期胃癌に対するESDの適応は拡大されつつあり，深達度SM1の病変や，ULを伴う病変でも条件を満たせば適応拡大病変とされる．しかし，SM1を内視鏡的に診断することは困難であり，臨床的にはM～SM1かSM2以深かの鑑別が求められる．深達度診断は，相関関係に基づく所見（癌の局在，組織型や肉眼型，大きさによるSM浸潤頻度），SM浸潤による直接所見を拾い上げることにより行われる．典型的なSM2癌や，深達度診断が困難な症例を提示し，診断の実際を述べる．

　The indication for ESD（endoscopic submucosal dissection）for early gastric cancer is being expanded. Even cancers with SM1 invasion and cancers with UL, if conditions are fulfilled, are considered to be indicated for ESD. But it is difficult endoscopically to diagnose the depth of the cancer as SM1, so it is important to diagnose whether the depth of the cancer is M～SM1 or deeper than SM2. To diagnose the depth of cancer, it is important to observe the direct findings caused by SM invasion of cancer, considering localization, histological type, microscopic appearance, and the size of the cancer. Showing typical SM2 cancer and a case in which it was difficult to diagnose the depth of cancer, we described the process of diagnosis of the depth of cancer invasion.