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Postoperative follow-up of patients with colorectal carcinoma by colonoscopy.

OBJECTIVE
To find out if colonoscopy is of use in the follow-up of patients who have been operated on for colorectal carcinoma.


DESIGN
Retrospective study.


SETTING
Department of diagnostic radiology, university hospital.


SUBJECTS
390 consecutive patients operated on for colorectal carcinoma during the 10-year period 1981 to 1990.


MAIN OUTCOME MEASURES
Number of recurrences, synchronous of metachronous tumours, and number and size of adenomas found on colonoscopy.


RESULTS
Neoplastic lesions were found in 175 (45%) of the 390 patients studied. There were 14 anastomotic recurrences and 12 new primary carcinomas. At operation for recurrent tumours Dukes' A or B lesions were found in half of the 14 patients who had no symptoms, and a quarter of the 12 who had had symptoms. Those with recurrent carcinoma were younger than those without. Adenomas 1 cm in diameter or more were found in 44 patients and 104 had adenomas less than 1 cm. In addition one carcinoid was found.


CONCLUSION
Colonoscopy gave a high yield of neoplastic lesions when used to follow-up patients after resection of colorectal carcinoma, particularly at six months, and resulted in half the recurrent carcinomas being diagnosed before the patients had symptoms. We recommend its use for follow-up of high risk patients, but further studies are needed to establish the optimum time intervals.