臨床病理学的にみた陥凹型胃癌の粘膜下組織浸潤

Clinicopathological Study of Cancer Invasion in Depressed Type Carcinoma of the Stomach

要旨　癌の状態像のうち，術前のX線・内視鏡検査により客観的に把握しうる4つの要素｛存在部位，大きさ，肉眼型，組織型｝から，sm浸潤の確率的推定について検討した．各要素をそれぞれ存在部位｛F線外部領域，F線内部領域｝，肉眼型｛陥凹型，隆起型｝，組織型｛未分化型癌，分化型癌｝とに分類した（胃癌の三角）．更に，8通りの胃癌の三角に癌の大きさ｛～2cm，2.1cm～｝を組み合わせて個々の胃癌の三角のsm浸潤率をみることによって，次のような結論が得られた．すなわち，（1）F線内部領域における陥凹性病変は未分化型癌で，癌の大きさとは無関係に70％以上はsm浸潤がある，（2）F線内部領域における陥凹性病変では常にLinitis Plastica型癌を念頭に置くべきである，（3）F線外部領域の陥凹型を示す癌のsm浸潤率は癌組織型よりも癌の大きさと相関していて，大きさ2cm以下ではsm浸潤30～40％，2.1cm以上では70～80％である．

　Preoperative estimation of invasion depth in gastric carcinoma was statistically studied with respect to the four factors easily obtained by radiological, endoscopic and biopsy examinations. These are location, size, macroscopic configuration and histological type of the carcinoma.

　Each factor was dichotomously divided as follows: Location (exterior or interior field divided by F-line), size (smaller than 2 cm, larger than 2.1 cm), macroscopic configuration (depressed or elevated type) and histological type (undifferentiated or differentiated). F-line means the margin of the fundic gland mucosa without intestinal metaplasia.

　The conclusions are as follows: 　(1) Almost all carcinomas seen in the fundic gland mucosa are histologically undifferentiated and macroscopically depressed type. And more than 70％ of these have already invaded the submucosa, independently of their size.

　(2) Depressed type carcinomas when seen in the fundic gland mucosa should lead to the suspicion of the socalled linitis plastica type.

　(3) Depressed type carcinomas situated outside of the fundic gland mucosal area are more closely related to the size than the histological type. About 30-40％ of carcinomas smaller than 2 cm and 70-80％ of carcinomas larger than 2.1 cm have invaded the submucosa.