原発部位が主として隆起型（Ⅰ＋Ⅱc型様）を呈したlinitis plastica型胃癌の1例

Gastric Cancer of Linitis Plastica Type with a Protruded Lesion in the Center of the Primary Lesion, Report of a Case

要旨　linitis plastica型胃癌は，胃底腺粘膜領域の陥凹性病変が粘膜下組織以深へ広範囲に，びまん性に浸潤し，線維性組織の収縮によって胃全体がleather bottleあるいは管状狭窄状態となる．その原発巣は，通常，腫瘤形成を伴わない．今回，われわれは原発巣が腫瘤を形成しているlinitis plastica型胃癌を経験したので報告する．患者（45歳，女性）は無症状であったが，胃集検で異常を指摘され，X線検査・内視鏡検査の結果Borrmann 1＋4型の診断で胃全摘出術が施行された．病理組織学的検索の結果，原発巣は大きさ1.7×2.2cmの隆起性病変で，粘膜下組織以深へ広範囲に浸潤しているlinitis plastica型胃癌と診断された．

　On Feb. 4, 1986, during a mass survey at our hospital, a 45 year-old woman was noticed to have a gastric abnormality. She was subjected to further examinations.

　X-ray and endoscopic examinations (Figs. 1 a ～ c, 2 a, b) showed a protruded lesion on the posterior wall of the upper corpus, irregular thickening of folds on the anal side of a polypoid lesion, and narrowing of the lumen of the stomach. The diagnosis made was that of gastric cancer of Borrmann type 1 ＋ 4, and total gastrectomy was performed on March 4, 1986.

　Pathological study revealed a relatively small lesion (3.3 × 2.7 cm) and a vast submucosal or deeper invasion of undifferentiated carcinoma cells, which are common findings in linitis plastica type of gastric cancer (Figs. 3 ～ 5, 6a ～ c).

　The characteristic feature of this case was the polypoid lesion in the center of the primary lesion.

　Although the origin and growing process of linitis plastica is still controversial, recent studies⁵⁾ explain it as a small superficial carcinoma in the fundic gland mucosa, usually of depressed form. It infiltrates the submucosa extensively before a cancerous ulceration is formed. Many reported cases of linitis plastica seem to support this theory and most of them describe a depressed lesion as the primary lesion.

　Our case, too, is no exception to this theory, and pathologically, it was diagnosed as linitis plastica. It is reported here because of the rarity of the polypoid-type lesion in the primary lesion of linitis plastica gastric cancer.