Background

Neoplastic large bowel lesions have been found that are flush with, or even depressed below, the colonic epithelium.1-5 These flat adenomas are reported to have an increased incidence of severe dysplasia when compared with polypoid lesions,1 ,4 ,6 ,7 and some have consisted exclusively of malignant cells. Thus, de novo development may be an alternative pathway of carcinogenesis.5 As a result, endoscopists are encouraged to be vigilant in discovering and removing these lesions. We report our experience of specific areas of normal depressed colonic mucosa that, macroscopically, have some features that are similar to true flat adenomas. Additionally, we …