Abstract
Sixteen cases of ha and IIa+IIc type early colonic cancers were classified into three subtypes (Figure 1) according to Sano's subclassification of IIa+IIc type early gastric cancer, namely "polyp" type (P type), "erosion" type (E type), and "deep invasion" type (D type). And these cases were examined clinically, macroscopically, and pathologically.The results were summarized as follows ; 1) There were eleven cases of P type, one case of E type, and four cases of D type. Cancerous invasion was limited to the mucosal layer in seven cases of P type, and reached the submucosal layer in other nine cases (Table 1). 2) Adenomatous component was found in nine cases of P type, but was not found in other seven cases (Table 1). 3) The characteristic endoscopic finding common to P type and E type was disappearance of normal vascular pattern. The surface color was normal in three cases and slightly reddened in eight cases. 4) In cases of D type, the mucosa surrounding the depressed area showed normal color, and the depressed area was discolored or had white coat, endoscopically (Figure 8, 9). 5) Two cases of D type, cancer cells of which invaded the submucosa, were small, namely, within 1 cm in diameter. It is considered to be valuable for the diagnosis of early colonic cancer to classify ha and ha + IIc type early colonic cancers into the above-mentioned three subtypes.
