ヒト胃腸上皮化生の研究―特にgoblet cell metaplasiaについて

A Study on Intestinal Metaplasia of the Human Stomach with Special Reference to Goblet Cell Metaplasia

　胃腸上皮化生は胃癌との関連において注目されてきているが，その成り立ちについては，まだ十分には解明されていない．その組織学的特徴が，杯細胞，吸収上皮，バネート細胞から成ることは広く知られているが，これらの特徴がいつの場合もそろって出現するわけではない．したがって，胃腸上皮化生にも，その程度と段階を知る必要から，これまでに，幾つかの分類が試みられており，それぞれに注目される（Table1）．

　今回，われわれは生検材料を用いて，組織学的，粘液組織化学的に，胃腸上皮化生を検討したが，その際，特に杯細胞の出現に注目した．杯細胞は腸上皮化生の特徴の中で，最も目立つものであり，多くの場合，吸収上皮を伴って出現するが，少数例では杯細胞のみが，正常の胃腺窩上皮の間に現れる場合がある．今回は主として，この現象に注目し，このような組織学的変化を杯細胞化生（goblet cell metaplasia）と名付け，腸上皮化生の成り立ちを解明する一助として検討した．

　Morphological and histochemical studies were performed on 917 biopsy specimens which were taken under endoscopy from 201 benign gastric diseases and their histological sections were stained with Hematoxylin-eosin (H・E), Periodic acid-Schiff (PAS) and Alcian blue at pH 2.5 (AB).

　In intestinal metaplasia, goblet cells have been reported to be accompanied by absorptive epithelial cells which are negative for PAS. In the present study, however, goblet cells were recognized among PAS-positive epithelial cells in 10.7% (98/917).

　Of 98 specimens 73 (8.0% of the total) were incomplete intestinal metaplasia (reported by Iida) with goblet cells and the columnar cells having both features of intestinal and foveolar epithelium. In the other 25 specimens (2.7% of the total), goblet cells were found among foveolar epithelial cells which contained normal amount of PAS-positive mucosubstance.

　We adopted the term “goblet cell metaplasia” to describe these features in the present study. All of goblet cell metaplasia were found only in the gastric pits and most of them were observed in the specimens taken from antrum and were accompanied by other metaplastic changes in the same specimens. These results suggest that goblet cell metaplasia is an early histological manifestation of intestinalization of the gastric mucosa.