Recent developments in the field of polyps of the colon are discussed. The WHO classification represents a definite improvement. Apart from standardization, non-neoplastic polypoid changes of varying etiology and hamartomatous polyps are clearly distinguished from neoplastic, non-malignant adenomas. The various changes are outlined briefly in their essential characteristics. Clear-cut differentiation from early invasive cancer is of considerable importance for practical therapeutic purposes. Focal carcinoma within an adenoma is referred to only if invasion through the muscularis mucosae is established, while all other changes confined to the mucosa are termed adenomas with focal epithelial atypia. With regard to the relation between adenoma and cancer of the colon, recent results on topographical distribution of adenomas through the colon are of considerable significance. From serial studies of biopsy and autopsy specimens on the one hand, and from assessment of colon carcinoma incidence compared with mortality rates in carcinomas of different localizations on the other, it is evident that special attention should be given henceforward to adenomas, possible precursors, and carcinomas in the upper segments of the colon.
Adenoma Carcinoma