胃のⅡb病変（点状Ⅱbと面状Ⅱb）の2症例―Congo red-methylene blue testによるⅡbの内視鏡診断

Endoscopic Diagnosis of Early Gastric Cancer of Type Ⅱb by the Endoscopic Congo Red-Methylene Blue Test

　表面平坦型早期胃癌Ⅱbは従来組織学的に初めて診断されるような微小癌が主体を占め，Ⅱb=微小胃癌と考えられてきた．しかし著者の一人である谷口はこれら微小癌としての点状Ⅱb以外に数cmに及ぶ拡がりをもった面状のⅡbが存在することを指摘している．内視鏡的には点状Ⅱbでは存在診断そのものが問題となり，面状Ⅱbではその拡がりを術前に正しく診断することが問題となる．われわれは極く早期の胃癌を確実に診断する方法として色素を用いたcongo red-methylene blue testを考案し，Ⅱbの診断に好成績を得ているが，今回は本法により術前に診断された微小な点状Ⅱbと広い拡がりをもった面状Ⅱbの2例を提示し，本法によるⅡbの診断成績について報告する．

　We demonstrated two cases, of early gastric cancer of type Ⅱb, which were correctly diagnosed by the endoscopic congo red-methylene blue test. In practice, the endoscopic procedure was as follows: The patients was given 20,000 units of Pronase and 50ml of 0.2M sodium bicarbonate solution containing 20 mg of Gascon orally 30minutes before examination, He was then asked to lie successively on his back, left side, stomach and right side in order to remove the mucus adhering to the mucosa. Twenty minutes before elldoscopy,4mg of Coliopan was injected subcutaneously. A gastrofiberscope was then inserted, and the interior of the stomach was inspected. A spray tube was inserted through the biopsy forceps channel, and 0.05% methylene blue solution was sprayed over the entire surface of the gastric mucosa. After observation of the microstructure of the gastric mucusa, a mixture of 0.3% congo red and 0.2M sodium bicarbonnate solution was sprayed over the gastric mucosa, and the blue discoloration of the gastric mucosa with methylene blue was examined. Then an augmented dose of Tetragastrin-NS was administered and color change of the gastric mucosa was observed through the gaetrofiberscope. In this test, gastric cancer bleached the cungo red and methylene blue sprayed over its surface and this appeared in sharp contrast to the red-mucosa of unaffected areas. Thus the spread of cancerous growth could be judged rather accurately and so the target area could be reached by biopsy in cases where there were few if any visual signs of abnormality.

　By routine endoscopic examination, correct diagnoses were provided in 85.0% of Ⅱb lesion of 10mm or more in diameter, but it was impossible to determine endoscopically Ⅱb lesion of less than 10mm in diameter. But the endoscopic congo red-me-thylene blue test made poible accurate determination of typical Ⅱb lesions of less than 10mm in diameter.