| [ Summary ] |
Endoscopic classification is very important to decide on proper treatment for colorectal cancer. Historically, macroscopic classification of early gastric cancer has been used to identify early colorectal cancer. Using macroscopic classification, the superficial type is classifled “type 0” and is divided into three distinct groups (I to III). In this institute, early colorectal cancer is classified as the protruded (polypoid) type, the superficial elevated type or the depressed type. The protruded type are classified as the pedunculated type (Ip), the semipedunculated type (Isp), the sessile type (Is), or the combined type (I + IIc) including depression on the lesion. The superficial elevated type (IIa) contain laterally spreading tumors (LST) and are diagnosed by the height of lesions being less than one third the size of the lesion. The depressed type is diagnosed when the existence of depressed areas, including absolute and relative depressions, are observed. Morphologically, those with slight elevation and central depression at their top are classified as IIa + IIc. Those of the absolute depressed type (IIc) with elevated borders are classified as IIc + IIa. In the case of those depressed lesions with central sesille protrusion, the classification would be IIc + Is. PG (polypoid growth) and NPG (non polypoid growth) classification are also useful in understanding the pathological characteristics of these lesions. In this study, the protruding type account for 25.5 % of the NPG type and the depressed type account for 30.4 % of the PG type. Macroscopic classification is an important topic for multicenter and international study based only on gross appearance. |