Correlation between colon adenoma and cancer

In the course of 1301 colonoscopies performed by the authors, in cases of 127 patients (9.76 %), 177 polyps were removed; 159 (89.83 %) out of them proved to be adenomas by histology. In 23 adenomas (14.46 %) malignant transformation was observed. The highest percentage of polyps was detected in the group of patients with tumours, and a somewheat lower proportion was found in the case of patients who underwent resection surgery because of tumours. A similar tendency could be seen concerning the malignant transformation of the removed adenomas. Our data seem to support the theory by Morson and Hermanek regarding the transformation from adenoma to cancer in the large bowe. Surgery is proposed in the following types of colon polyps: (1) polyps unremovable by endoscopic polypectomy, even by piecemal snare excision