びまん浸潤型胃癌と鑑別を要した早期胃癌を合併したびまん性囊胞性形成異常（diffuse cystic malformation）の1例

Diffuse Cystic Malformation of the Stomach with Adenocarcinoma that can Mimic Diffusely Infiltrative Cancer, Report of a Case

要旨　患者は54歳，男性．検診で胃の異常を指摘され受診した．胃X線検査および内視鏡検査では，幽門前庭部に不整形陥凹性病変を認め，体部は皺襞が腫大し同領域の胃壁は肥厚し，巨大皺襞胃の様相を呈していた．皺襞の腫大は一様ではなく，既存の粘膜ひだの走行を保ちながら腫大の著明な皺襞と目立たない皺襞が不規則に混在しており，また，伸展性も比較的保たれていた．超音波内視鏡検査では，第2～3層に多発する小囊胞を認めたが，第4層の肥厚はなかった，良性の巨大皺襞症を合併した胃癌の診断のもとに胃切除を行った．病理組織学的に体部の巨大皺襞は形成異常としてのびまん性囊胞性形成異常と診断した，本疾患は巨大皺襞胃の様相を呈することが多く，本症例の特徴的な肉眼所見および超音波内視鏡所見は，びまん浸潤型胃癌など巨大皺襞を来す他の疾患との鑑別診断に有用であると考えられた．

　A 54-year-old man was admitted to our hospital for further examination and treatment of gastric cancer discovered during a health check. X-ray and endoscopic examination showed an irregular-shaped depression with surrounding elevation on the greater curvature of prepyloric area. The biopsy specimen taken from this lesion revealed poorly differentiated adenocarcinoma and signet-ring cell carcinoma. Enlarged folds on the greater curvature of the gastric body and wall thickening were observed. These findings looked like diffusely infiltrative cancer. However, the degree of swelling was not uniform and the pliability of the gastric wall was rather good. Endoscopic ultrasonography showed multiple cystic lesions in the thickened 2nd to 3rd layer of the gastric wall. The 4th layer was intact. Total gastrectomy was performed. The pathological diagnosis of the resected specimen was diffuse cystic malformation of the stomach with adenocarcinoma.