The value of colonoscopic surveillance after curative resection for colorectal cancer or synchronous adenomatous polyps
G. Carlsson, N. J. Petrelli, H. Nava, L. Herrera and A. Mittelman
Department of Surgical Oncology, Roswell Park Memorial Institute, Buffalo, NY 14263.
Between 1975 and 1984, 270 patients underwent a potentially curative
resection for colorectal carcinoma. One hundred eighty-eight patients (70%)
underwent preoperative colonoscopy, of which 129 patients (69%) were
followed up with at least two postoperative colonoscopies. In 91 patients
(70%), preoperative colonoscopy revealed no synchronous adenomatous polyps
or cancer. Synchronous adenomatous polyps were found in 35 patients (27%),
and three patients (2.3%) had a synchronous invasive cancer. Nineteen (54%)
of the 35 patients with synchronous adenomatous polyps developed
metachronous adenomatous polyps during the follow-up period compared with
24 (26%) of 91 patients without synchronous adenomatous polyps. The median
interval to the development of metachronous adenomatous polyps was 19
months, and all of these polyps were 1 cm or less in size. Patients with
synchronous adenomatous polyps less than 30 cm from the primary lesion
(68%) developed metachronous polyps more often than did patients whose
synchronous adenomatous polyps were more than 30 cm from the primary lesion
(37%). Preoperative colonoscopy is important for determining synchronous
pathology and identifying patients at risk for metachronous polyps.
