linitis plastica型胃癌，特にその初期病変の診断―内視鏡診断（EUSを含む）を中心に

Endoscopic and Endoscopic Ultrasonographic Findings of “Pre-and Latent Linitis Plastica” Type Gastric Cancer

要旨　linitis plastica（LP）型胃癌の初期病変3症例を提示した．LP型胃癌の初期病変は胃底腺領域のⅡcとして発生する．その浸潤予測はpre LP型胃癌では困難なことが多いが，陥凹周囲のひだのわずかな太まりや発赤調の陥凹底が診断の手がかりとなる可能性がある．latent LP型胃癌では陥凹周囲の台状挙上と硬さ，ひだ走行の滑らかさの欠如により診断可能である．EUSでは癌に伴う線維化の部分はlow echoとして認識できたが，それを越えて浸潤する癌細胞は同定不能であった．胃体部のⅡcで未分化型癌が生検で証明された場合は，伸展性が保たれていてもscirrhousな浸潤の可能性を考え，これらの所見に注意すべきである．

　We presented three cases of pre-and latent linitis plastica (LP) type gastric cancer. Early LP is observed in the gastric body as a small depression. Although the invasion of pre LP is difficult to diagnose before operation, the red bottom of the depressed lesion and slight thickening of folds around the depression may be a clue for the diagnosis. The findings of plateau-like elevations around the depressed lesion and folds with zigzag outlines observed in latent LP suggest scirrhous invasion of undifferentiated cancer. By endoscopic ultrasonography only the fibrosis within the cancer can be detected as a low echoic lesion, but cancer cells with scirrhous invasion around the fibrosis cannot be recognized. When an undifferentiated cancer is detected from a IIc lesion in the gastric body, we should pay attention to these endoscopic findings, considering the possibility of its being a scirrhous invasion.