| [ Summary ] |
Recent advances in colonoscopic diagnostics have allowed the identification of small depressed lesions with greater frequency. It is, however, occasionally difficult to distinguish depressed adenomas and cancers from non-neoplastic depressions. To clarify the difference between the two, the distribution of the neoplastic pits at the margin of depressed tumors was examined. Grossly, the distribution patterns were classified into two types. The first type was characterized by complete separation of the area of neoplastic pits and non-neoplastic pits. The second type was characterized by a distribution of neoplastic pits lying between the covering epithelial areas of non-neoplastic pits. The classification of the distribution of neoplastic pits at the margin of the depressed area was useful not only to distinguish between cancer and adenoma but also to distinguish tumors from non-neoplastic lesions. |