大腸早期癌のX線診断

X-ray Daignosis of Early Carcinoma of the Large Bowel

　わが国では，胃のX線診断学にくらべ，大腸診断の遅れが，最近よく問題になる．

　大腸疾患の頻度が胃に比して極めて，少ないこと，検査法に統一性のないこと，などがそのおもな理由であろう．実際，これまでのわれわれの症例をふりかえってみても，大腸癌は，ほとんどが進行癌であり，早期癌はきわめて少ないのが現状である．

　An attempt has been made to define early carcinoma of the large bowel entirely in the same way as that of the stomach. In the period from October, 1967 to November, 1969, a series of 104 cases (122 lesions) of carcinoma of the large bowel have been operated upon in the Department of Surgery, Cancer Institute Hospital. Of these, early carcinoma has been experienced in 17 cases (24 lesions) including Ⅱ cases of single lesion, one of double lesions and 4 cases (10 lesions) associated with advanced carcinoma. Three lesions of carcinoma in situ are included in the category of early carcinoma. It accounts for 11.5 per cent (12/104 cases) of all carcinomas of the large bowel experienced for the past two years.

　As with early cancer of the stomach, that of the large bowel is macroscopically classified into 3 varieties: type I (15 lesions), type Ⅱa (5 lesions) and type IIa+IIc (4 lesions). Pedunclated type I was most frequent, comprising 42 per cent (10/24 lesions) of all early carcinomas.

　The greatest diameter of early carcinoma of the large bowel was less than 40mm. All lesions under 20 mm in the largest diameter were early carcinomas with the exception of one lesion.

　Roentgenologically, 11 lesions in 10 cases of early carcinoma were demonstrated. Of these, deformity of the lumen was seen in 4 lesions of Type Ⅱc, and in the remaining 7 lesions (6 of type I, and one of type Ⅱa) tumor shadow appeared on the double contrast radiograbh with no deformity of the lumen. Double contrast method was most effective in demonstrating these small polypoid lesions, and in some cases, compression method was satisfactory. All lesions associated with advanced carcinoma were overlooked.

　For detection of early carcinoma, it may be necessary to demonstrate polypoid lesion, at least smaller than 20 mm, by double contrast method. When a lesion 10mm or less in diameter is demonstrated, the possibility of advanced carcinoma may be excluded.

　In this paper,4 cases of early carcinoma are presented.