[Assessment for development of superficial colorectal neoplasm--endoscopic and clinicopathologic analysis of 149 submucosal invasive carcinomas].

We performed the endoscopic and clinicopathologic analysis for the development of superficial colorectal carcinoma, using 149 submucosal (sm) invasive colorectal carcinomas. It was observed that superficial colorectal carcinomas had a tendency to rise by their sm massive invasion. In this study, we judged that the sm colorectal carcinomas originated from superficial colorectal carcinoma were 37 (25%) of 149 lesions, and their distribution in the colon and rectum was similar to that of advanced colorectal carcinomas, although the lesions originated from non-superficial (polypoid) colorectal carcinoma did not show so tendency. On the other hand, sm colorectal carcinomas originated from superficial colorectal carcinoma contained the evident adenomatous components in 7 (19%) of 37 lesions and had significantly higher incidence of lymph node metastasis than those originated from non-superficial (polypoid) carcinoma. These results suspected the facts as follows; 1) Superficial early colorectal carcinoma may be compatible as the origin to advanced colorectal carcinoma and has higher malignant potential than non-superficial early carcinoma. 2) Superficial colorectal carcinoma might also have the route of the development of "adenoma-carcinoma sequence", as well as "de novo" histogenesis.