Follow-up colonoscopy in patients with colorectal adenomatous polyps

Multiple follow-up colonoscopies were performed in 44 asymptomatic patients after polypectomy of colorectal adenomatous polyps. Twenty-six patients (59%) developed new adenomatous polyps. In 81% the new polyps were located in the same segment of the colon where a previous polyp had been totally removed. Polyps removed during follow-up, compared with the initial polyps, revealed significantly more benign and smaller polyps. The number of initial polyps together with occurrence of atypia were factors determining a short time interval for developing new adenomatous polyps. The mean time for developing a 5-mm or larger polyp was significantly longer than polyps less than 5 mm in diameter.