病理組織構築よりみた深達度診断の問題点

Clinicopathological study on the diagnosis of gastric cancer invasion into the deep layer of the gastric wall

　胃癌の診断学は，外科医や病理学者の協力によって，診断している対象の肉眼所見や，これを形作る病理組織構築を熟知して，X線，内視鏡所見からこれを類推し，また逆に切除材料からX線，内視鏡所見の解釈をし直すといったことの繰返しによってすすめられてきた．

　胃癌の深達度診断に関しては，多数の業績があるが^1)～3)，その多くは，単純に早期癌，進行癌とわけて，X線，内視鏡所見の出現頻度の差を推計学的に検定するといった方法である．

　One hundred and eleven cases of gastric cancer of depressed dype smaller than 3.5 cm in maximum diameter were selected for this study. And comparative study botween histopathological findings and the findings of radiology and endoscopy was made. I . Studies on radiological and endoscopical findings suggesting cancer invasion over the muscularis mucosa.

　The findings such as 1) sharply demarcated rigidity of gastric wall (small filling defect), 2) elevated and fused mucosal fold at the rim of the depressed lesion, 3) radiolucency around depressed lesion in compression study, 4) tortuosity of converging folds in double contrast study, and 5) plateau like appearance of the depressed lesion in endoscopic feature.

　Mechanismus in No. 1), 3), 4) and 5) findings were discussed. Findings of No. 3), 4) and 5) were considered as an expressing of the rigidity en face.

　Ⅱ. Correlation between cancer cell mass in the submucosal layer and its diagnostic ability.

　1) In order to express the cancer cell mass of the submucosal, following “spreading index” and “thic-kening index” were proposed.

　Spreading index (S. L)

　＝area of submucosal infiltration × 100 (%)

　　area of mucosal infiltration

　 Thickening index (T. I)

　＝thickness of submucosal infiltration × 100 (%)

　　entire thickness of gastric wall

　2) Correlation between S. I, T. I. and its diagnostic ability by X-ray and endoscopy, was investigated. S. I, T. I. and diagnostic ability of cancer cell mass in the submucosal layer were well correlated each other.

　In case with over 60% S. I, diagnosis of submucosal massive infiltration was easy in most instances. In those with less than 15% S. I, it was impossible. In cases with 15 to 30% S. I, the diagnostic ability was influenced by T. I.