胃底腺型腺癌の臨床像と内視鏡的特徴—205病変の臨床像のまとめ

Clinical Characteristics and Endoscopic Findings of Gastric Adenocarcinoma of the Fundic Gland Type：Summary of Clinical Features of 205 Lesions

要旨●胃底腺型腺癌（GA-FG）は比較的まれな腫瘍と考えられていたが，その疾患概念が提唱されてから約15年が経過した現在では，多くの医療機関で診断および治療が行われるようになっている．本疾患は男性に多く認められ，Helicobacter pylori感染の有無にかかわらず発症しうる点が特徴であり，主としてU領域に発生する．内視鏡診断に際しては，胃底腺領域の白色調病変の発見にとどまらず，腫瘍の存在する層構造，集合細静脈の走行，ならびに腺開口部の形態変化を正確に評価することが極めて重要である．本疾患は微小病変であっても粘膜下層（SM）への浸潤を認めることがあるが，大きな腫瘍径や高い隆起を除き，SM浸潤を示唆する決定的な内視鏡所見はない．今後は，SM浸潤の可能性を予測する新たな内視鏡的指標の確立が望まれる．

　The concept of gastric adenocarcinoma of the fundic gland type（GA-FG）, was proposed 15 years back and is now widely recognized among general gastroenterologists. The endoscopic characteristics of GA-FG are also becoming more evident with the increasing number of cases. GA-FG is more likely to affect men, occurs mainly in the upper region of the stomach, and is independent of Helicobacter pylori infection. The key points for endoscopic diagnosis include identifying whitish lesions in the fundic gland area, determining the layer in which the tumor is located, and detecting abnormalities in the course of collecting venules along with the changes in glandular openings, which facilitates the detection of even small lesions.

　Despite its small tumor size, GA-FG tends to invade the submucosa（SM）. However, no definitive endoscopic findings have indicated SM invasion. However, lesions displaying a high degree of elevation and large tumor size might indicate SM invasion.