One of the more difficult problems facing proctologists, abdominal surgeons, and pathologists is the question of proper treatment for adenomas in which carcinomas have arisen that have not yet invaded the muscular bowel wall. The decision must be made as to whether it is safe to treat these lesions by local removal or whether a radical resection should be performed immediately. In this paper, we hope to settle this problem at least partially. In 1948, Scarborough and Klein1reported a study of 458 patients with polypoid disease of the colon and rectum. In this series there were six pedunculate adenomas of the colon for which bowel resection had been performed and in which areas of invasive carcinoma were found. Although there was no invasion of the pedicle in any case, there were regional lymph node metastases in three of the operative specimens. This report raised the question as to