Colorectal adenomas: clinical and morphological aspects. A review of 166 polyps from 124 Dutch patients.

In a series of 124 consecutive Dutch patients the clinical and morphological features of 166 endoscopically removed colorectal adenomatous polyps were reviewed. The most frequent clinical symptom was manifest blood loss with the stools (51%), but no specific adenoma symptom seemed to exist. Barium enema X-ray examination was done in 108 patients, whereas all patients were colonoscoped. The routinely performed barium examinations detected 71% of the polyps that were found during endoscopy, but not all X-ray examinations were air contrast barium enemas. A good correlation between the localization of the adenomas after both diagnostic modalities was found, indicating that more than 80% were located in the left part of the colon. Nineteen percent of the patients had had a metachronous (pre)neoplastic lesion removed from their large bowel previously, while 40% of the patients had a synchronous polypoid lesion at the moment of polypectomy. Sixty-two percent of the adenomas were tubular, whereas 38% were villous adenomas. There was a strong correlation between size and villous architecture (r = 0.38; p less than 0.001). The epithelial dysplasia was mild in 21%, moderate in 70% and severe in 9% of the adenomas. The degree of dysplasia correlated well with the villous type of mucosal growth (r = 0.24; p less than 0.005). These findings indicate that, 1) there are no colorectal adenoma specific symptoms, 2) to detect colorectal adenomas colonoscopy is the investigation of choice, 3) after the detection of a colorectal adenoma the whole colon should be investigated, 4) colorectal adenoma patients should be kept under surveillance, and 5) determination of the diameter and of the degree of epithelial cell dysplasia may be helpful in assessing the biological behavior of an adenomatous polyp.