Abstract
Fifty-seven early colorectal cancers were subjected to a clinicopathological analysis. When compared to pedunculated early cancers, sessile early cancers had greater tumors in size and a lower incidence of association of adenoma. Right-sided cancers were predominantly sessile submucosal cancers. Sessile submucosal cancers without adenoma tended to have greater tumor diameter. No invasion into the lymph or venous vessels was found in mucosal cancers. However, submucosal cancers, if those had some factors such as sessile type, tumor diameter of 2 cm or more, deep submucosal invasion, no adenoma component by biopsy, and aneuploid pattern in DNA ploidy, had probable lymph vessel invasion with a high incidence. Accordingly, curative resection should be indicated for cases having such risk factors, considering of possible occurrence of metastasis and recurrence. Endoscopic or local resection can offer satisfactory outcomes for cases without such risk factors.