Abstract
Thirty cases of multiple carcinoma of the colon and rectum were clinicopathologically studied.
These 30 cases, including 25 synchronous and 5 metachronous ones, represented 4.8% for all operated cases (625) for colorectal carcinomas, or 5.1% for curative resection cases (587). In synchronous multiple carcinomas, the first carcinoma was commonly found in the rectum and sigmoid colon. In metachronous carcinomas, the first carcinoma was predominantly located in the sigmoid colon and the second one, in the ascending colon. As to the depth of invasion of the carcinoma, a combination of advanced and early carcinomas were frequently seen (64.0%) in synchronous cases, while a combination of both advanced carcinomas was noted in all metachronous cases. Association of adenomatous polyps was found in high frequencies such as 66.7% as a whole, 60.0% in synchronous, and 80.0% in metachronous cases. Frequency of familial occurrence of carcinoma was 53.3%, that of colorectal carcinoma being 20.0%. The 5-year survival rate of 25 curative resection cases was 71.6% in synchronous carcinomas and 100% in metachronous carcinomas, respectively, which would be similar in the former and favorable in the latter, compared to 73.1% in sigle carcinoma cases. From these findings, in the treatment of multiple colorectal carcinomas, it would be important preoperatively and accurately to diagnose the second carcinoma probably being in an early stage or possibly coexisting adenomatous polyps as well as the first advanced carcinoma in synchronous cases, and strictly to follow up after operation for the first carcinoma in metachronous cases.
