A conservative approach to adenomas containing invasive carcinoma removed colonoscopically.

A controversy exists as to the correct therapeutic approach to colorectal polyps that contain malignancy and are removed colonoscopically. This paper presents our experience in the management of such polyps. Between 1977 and 1983, a total of 117 patients underwent colonoscopic polypectomy for 178 adenomas. Nine adenomas from nine patients showed carcinomatous invasion across the line of muscularis mucosae. None of these carcinomas was poorly differentiated and in all but two cases there was histologic evidence of complete excision. Seven patients whose adenomas containing foci of malignant changes were treated by polypectomy alone are alive without recurrence at periods from six months to over five years (mean, 40 months). The two patients in whom endoscopic removal of cancerous adenomas was found to be either doubtfully complete or incomplete, had further surgical treatment; both are alive and well after one and five years, respectively. Nine other patients whose adenomas containing malignant changes were considered unsuitable for colonoscopic polypectomy, underwent surgical resection and in none was regional lymph node or distant metastases found at laparotomy. In conclusion, our results of local endoscopic excision for adenomas containing malignant changes suggest a conservative approach to such polyps and this policy is supported by the finding that, in none of our operated patients was there any evidence of metastatic disease.