| [ Summary ] |
For the purpose of evaluating radiographic characteristics of the depressed type of colorectal tumors, the radiographic and pathologic findings of 203 submucosal cancers were analyzed. There were 195 protruding lesions (91.1%), but only 8 depressed lesions (3.7%). Protruding lesions were analyzed using the classification of polypoid growth (PG) type and non-polypoid growth (NPG) type. In the protruding lesions, the incidence of NPG type was 54%. Therefore, more than half of submucosal colorectal cancers were considered to be superficial (depressed) type origin, but most of them showed protruded features. Three among 195 protruding submucosal cancers were demonstrated. All three cases were NPG type and most of their mucosal structure was maintained. Irregular central shallow depressions were visualized in each case radiographically. We think these findings correspond to the radiographic initial image of invasive colorectal cancer, and are the most important findings in radiographic diagnosis of colorectal tumors. |