Abstract
The colon tumor sized more than 20 mm in diameter which developed mainly in the horizontal direction was defined as laterally spreading colorectal tumor(hereinafter LST). We studies the selection of appropriate method of therapy for LST, classified two types, Granular type LST which has mainly granules and nodules aggregate and Non-Granular type LST which has flat elevation without granules. Endoscopic and radiological analyse were done about the character of the surface, and histopathological investigation was done about the depth of invasion, vertical distance of sminvasion in the cases of sm-cancer, histological type of invasion part, existence of budding, and positive rate of ly, v and n, which were important factors for decision of the method of therapy. In cases of the granular type, selection of method of therapy should be done based on the size of constituent components, that is, protrusion component in the surface and the existence of relative depression. In cases of non-granular type, that should be done based on the existence of elevasion in non-granular part.
