1959 年 71 巻 8-2 号 p. 5271-5278
Recently the radical operation for rectal cancer, which preserves the function of anal sphincter, is regarded as an excellent method. But from the view of its radicality there are some opinion against it. Recently to decide how much normal tissue under the tumor must be resected has become a big problem.
To clarify this problem, a histological study was performed on the rectal wall under the tumor, and frequency and mechanism of retrograde spreading were investigated.
1) In specimens from 49 rectal cancers, which were resected by abdominoperineal combination method with colostomy (MILES method) and had their lower ends beyond the ampullar part, all tissues of them and the skin of anal part were cut into complete serial sections and investigated microscopically.
2) In 2 of 49 cases retrograde spread was found.
3) In one case, a successive infiltration was found mainly in muscular layer 3.5cm from the macroscopical lower end of tumor. In an other case down 1cm from the lower end of tumor at the outside of muscle layer of the rectum, lymphatic metastasis closely attached was found.
4) In both cases the primary foci and also from literatures, in the radical operation of rectal cancer keeping the function of anal sphincter, it is regarded quite sufficient if the normal colon is resected 5cm below the lower end of tumor in case the lower end of tumor lays beyond to the ampulla.