Colorectal polyps: an endoscopic experience.

Between April 1975 and December 1985, 870 colonoscopies were performed and 803 colorectal polyps were managed endoscopically. Thirty-nine per cent of the polyps were metaplastic polyps. The majority (59%) of polyps less than 5 mm in diameter were metaplastic polyps. Of the adenomatous polyps 63% were tubular, 32% were tubulovillous and 5% were villous histologically. Sixty-two per cent of all polyps were found in either the sigmoid colon or rectum. There was a higher proportion of tubulovillous adenomata (32%) than reported previously. Twenty-two patients had polypoid carcinomata and eight were removed endoscopically; four were subsequently referred for surgical excision because of 'incomplete' removal but no residual tumour was found. Fifty-three per cent of patients examined had more than one polyp. Fourteen of 19 patients who presented with a single polyp were found to have further polyps when examined subsequently and 29 of 39 patients with multiple index polyps had more polyps at follow-up. Perforation occurred in three patients, and two patients required blood transfusion following endoscopic polypectomy. It is suggested that total colonoscopy should be undertaken in all patients with polypoid disease because of the distribution of polyps found. It is further suggested that the findings of this study may be related to the high incidence of colorectal carcinoma in New Zealand.