食道胃接合部癌とBarrett食道腺癌の鑑別は必要か─臨床の立場から

Comparisons of Background Factors and Clinical Outcomes of Endoscopic Submucosal Dissection between Gastric Cardiac Adenocarcinoma and Barrett's Esophageal Adenocarcinoma in Siewert Type II Pathological T1 Adenocarcinomas

要旨●背景：Siewert分類Type II食道胃接合部（EGJ）癌は，胃噴門部癌（GCA）とBarrett食道腺癌（BEA）が混在しているため，内視鏡粘膜下層剝離術（ESD）適応や治癒切除の定まった基準がない．目的：Siewert分類Type IIのEGJ癌ESD症例からみたBEAとGCAの臨床病理学的特徴を明らかにする．対象・方法：2006〜2014年まで当院でESDが行われたSiewert分類Type IIのEGJ癌139例（BEA 54例，GCA 85例）を対象とした．比較項目は患者背景，内視鏡所見，内視鏡治療成績とした．結果：平均年齢はBEA群が有意に若年であり，生活習慣病の各因子，重複癌に有意差はなく，異時多発癌はGCAが有意に高率であった．腫瘍長径はBEAが小さく，肉眼型はBEAは隆起型，GCAは陥凹型の割合が高率であった．RAC，食道裂孔ヘルニア率は有意にBEAが高率であり，腸上皮化生はGCAが高率であった．一括切除率，局所再発率，合併症は両群に有意差なく，治癒切除率は有意にBEAが低率であった．結論：Siewert分類Type IIのEGJ癌において，BEAはH. pylori陰性の若年者に多く，内視鏡治療の非治癒因子になりうる．

　Background：In esophagogastric junction adenocarcinoma, both GCA（gastric cardiac adenocarcinoma）and BEA（Barrett's esophageal adenocarcinoma）originated in short-segment Barrett's esophagus are included. This study aimed to compare background factors and clinical outcomes of ESD（endoscopic submucosal dissection）between GCA and BEA.

　Materials and Methods：We enrolled 139 patients who underwent ESD between 2006 and 2014 at the cancer institute hospital. We compared background factors, endoscopic features, and clinical outcomes of endoscopy between 54（38.9％）patients with BEA and 85（61.1％）patients with GCA.

　Results：The curative resection rate of GCA was higher than that of BEA. There were no significant differences in background factors between the two groups. The risk factor for non-curative resection, lymphovascular invasion, and depth of invasion was higher in the BEA group than in the GCA group.

　Conclusion：Although there were no significant differences in background factors, BEA was found to be a risk factor for the non-curative resection of ESD.