表層拡大型胃癌のX線診断

X-ray Diagnosis of Superficial Spreading Carcinoma of the Stomach

　表層拡大型胃癌という表現は，今までいろいろの意味に使用されてきたようであるが，その語感から，直感的に浸潤範囲，Ⅱb（類似Ⅱb），残胃の癌といったことを連想しがちである．このように表層拡大型胃癌という言葉から，ある特定の胃癌を感覚的に想定することはできる．しかし，その大きさや肉眼所見などについて，明確な基準がないように思う．今までにも，表層拡大型胃癌について，幾つかの定義なり，基準は作られている．が，どれを頼りにしたらよいか迷ってしまう．そこで，安井にならい，癌研外科で手術した早期胃癌の症例を整理し，表層拡大型胃癌について，X線診断の立揚から検討してみた．

　A study is made on the x-ray diagnosis of superficial spreading carcinoma of the stomach, based on 484 cases of early gastric cancer which had been operated upon at the Dept. of Surgery, Cancer Institute Hospital in the period of 8 years from 1965 to 1972. The superficial spreading carcinoma is defined as carcinoma whose area is larger than 5² cm² (Yasui, 1970) and 65 of 484 cases are regarded as such, including 12 cases of polypoid type and 53 cases of depressedy type. As with the location of them, 44 cases occupy the gastric angle mainly and most of them ride on the lesser curvature.

　One of the most important problems in the x-ray diagnosis of the superficial spreading carcinoma of the stomach lies in determination of the proximal border of cancerous infiltration. Generally, the proximal border is determind without difficulty in the cases of polypoid type. However, in the typical three cases of them, the diagnosis of the whole area is difficult, because they reveal IIa or IIb-like spreading pattern at their peripheral portion. In the cases of depressed type, the diagnosis of the whole area is easy if it is in the range of 5²～6² cm². However, the diagnosis is difficult as area becomes bigger. The diagnosis is especially difficult if the area is over 8² cm².