pre-linitis plastica型胃癌の形態学的特徴―内視鏡の立場から

Characteristics of Endoscopic Findings of “Pre-linitis Plastica” Type Gastric Cancer

要旨　①原発巣が胃底腺領域粘膜の小さな未分化型陥凹型癌であり，②潰瘍を合併せず，③粘膜内病巣に比べ粘膜下浸潤の拡がりが大きく，④深達度はsmまたはmpを満たすものをpre-linitis plastica（LP）型癌として検討を行った．pre-LP型癌は対象3,269例中1例，0.03％にすぎなかった．その内視鏡像をみると，原発巣は粘膜ひだと粘膜ひだの間に埋もれるように存在する，ひだ集中を伴わない極めて小さな陥凹で，その周囲に限局性の粘膜ひだの肥大を認めるが，空気伸展すると肥大した粘膜ひだは目立たなくなり，台状挙上の所見を呈した．これが特徴と言えそうである．

　Objectives: We conducted this study to clarify the characteristics of endoscopic findings of pre-linitis plastica type gastric cancer (pre-LP). Patients and methods: There were 3,269 cases of gastric cancer patients who underwent gastrectomy at the Cancer Detection Center of the Miyagi Cancer Society in the 19-year period from 1980 to 1998. We tried to pick out the pre-LP patients according to the pathological criteria as follows:

　①The origin is undifferentiated type small cancer in the fundic glands area, ②There is no association with peptic ulcers or ulcer scars, ③Submucosal cancerous extension is larger than intramucosal cancerous extension, ④The depth of cancerous invasion is sm or mp.

　Results: (1) We found that these criteria were veuped in only one case (0.03%) of pre-LP cases.

　(2) The endoscopic characteristics of pre-LP which we discerned in our survey were as follows: 　①The origin was a small depression without converging folds between mucosal folds.

　②The plateau-like elevations became apparent when a lot of air was used.