対称性潰瘍から見た胃潰瘍の発生・成熟過程―その2．線状潰瘍について

Development and Ripening Process of Gastric Ulcer Judged by Symmetrical Ulcers: part 2. On Linear Ulcer

　胃潰瘍の発生論がやさしそうに見えて，実際は一筋縄ではいかぬしたたかさを持っていることは，前稿の「その1．Kissing ulcerについて」で述べた通りである．またこうした難しさを乗り越える便法として特殊な形を有する潰瘍を例にとるのも一法であると述べた．その意味で本稿の線状潰瘍を目標とした発生論も意味があるわけであるが，定型的な円形潰瘍とは形が違いすぎて，あるいは参考にはならないかもしれない．すなわち円形潰瘍とは全く異なった発生機序を持っているかもしれないという危惧の念はにわかには払拭しがたい．

　さて線状潰瘍の発生機序については，すでに2，3の説がある．最も有力な説が，ある程度線上に並んで発生した複数の潰瘍（多発潰瘍といってもよいかもしれない）の間が繋がるとする説，あるいは何らかの理由で発生した短いながらも線状の傾向をもった潰瘍がその尖端で再発を繰り返すことによって線の延長をもたらすとする説などである．これらの説にはいずれも内視鏡的あるいは病理的な観察による裏づけがあると言われている．しかし線状潰瘍が一挙に形成されるという説はほとんど主張されていない．私どもは偶然の機会からこの新しい第3の説を支持する症例を得た．以下それについて述べる．

　1, Although the number was limited, we were able to demonstrate in some cases that linear ulcers developed in a very short time among boys and girls of teen-age, especially in their first half. This fact is a refutation against the commonly acknowledged assumption that linear ulcer be formed by a chain of ulcers occurring on a line at various places.

　2, These ulcers developed as a result of worries of junior high school students about their entrance examination to high school or their selection of jobs. In other words, we are sure these ulcers belong to a kind of stress ulcer.

　3, When we take into account a fact that resection of the stomach because of linear ulcer usually takes place in the age group 40~60, it can be assumed that ulcers that developed at a very early age as exemplified in our cases could lie dormant for long years to come only to recur or become manifest at the time of stress during one's middle years. Of course we do not intend to assert that all linear ulcers be formed in the same way. As there would be various kinds of ripening process in kissing ulcer, so there should be no reason why there would not be various kinds of ripening process in linear ulcer as well.

　4, At all events, a linear ulcer once developed would tend to extend by recurrence further on a line along the original linear ulcer.

　5, It is not at all clear to us why linear ulcer develops from the outset as we are also quite in the dark about the mechanism of the formation of kissing ulcer. However, these questions may all the more afford us with some clues to the mechanism of ulcer development.