Abstract
Radiographic and endoscopic diagnosis of synchronous multiple cancer of the large bowel was studied, based on 70 cases which had been operated on and histologically proven at the Cancer Institute Hospital in a period 34 years from 1946 to 1979, excluding cases of polyposis of the large bowel, and the following result was obtained. Seventy cases of the synchronous multiple cancer comprise 4.7% of all operated cases in the same period. Lesions of multiple cancer were most frequent in the rectum and sigmoid colon, comprising 59.5%. All multiple lesions had not been detected by the radiographic examination in many cases in a period of 28 years from 1946 to 1973 because the double contrast radiography has not been established in this period. Endoscopically, lesions located proximal to the mid-sigmoid colon had not been observed because a rigid rectoscope was used for the most cases. However, in a period of 6 years from 1974 to 1979 when the double contrast radio-graphy has been established and fiberscope has been routinely used, there had been few cases which were missed by radiology and/or endoscopy except for cases with obstruction and marked stenosis due to cancer. In this period both radiology and endoscopy revealed the lower detection rate of early cancer than advanced cancer. Endoscopy revealed a tendency to detect lesions proximal to primary cancer less effectively than the primary one, itself and those distal to it. It is considered that small lesions may be missed by radiology with no relation to a presence of stenosis and that there is the least possibility for the lesion distal to a primary cancer to be missed by endoscopy. In order to obtain the better diagnostic yield of multiple cancer, an attention should be focused on the rectum and sigmoid colon where it is most frequent, and when one cancer is detected the same segment and an adjoining segment should be scrutinized on the assumption that at least two more cancers may be present.
