Colonoscopic surveillance after surgery for colorectal cancer

Intensive colonoscopic surveillance after resection of colorectal cancer (CRC) has been shown not to improve outcome. The National Health and Medical Research Council of Australia (NHMRC) has recently published guidelines recommending appropriate surveillance intervals after CRC resection. The aims of the present study were to assess current and past patterns of postoperative CRC surveillance and to determine the yield of neoplasia from such surveillance.

An audit was performed of all patients who underwent colonoscopy following surgical resection of CRC from 1989 to 2001. Two groups were assessed: (i) all patients undergoing surveillance colonoscopies; and (ii) all patients diagnosed with CRC at Sir Charles Gairdner Hospital (SCGH) who subsequently had postoperative colonoscopies. Patients who had their index colonoscopy at the study centre and who subsequently underwent surveillance colonoscopies were studied in detail. Yield for neoplasia, patterns of surveillance and concordance with NHMRC recommendations were determined.

There were 990 surveillance examinations performed and colorectal adenomas were identified in 184. However, only one case of recurrent cancer was detected. There were a total of 161 patients who had CRC diagnosed and underwent surveillance at SCGH. Of these patients, 75% underwent colonoscopy at 12 months after resection and 48% of these cases underwent a further examination within 12 months. Only 23% of examinations concurred with NHMRC recommendations and practice has not changed with release of these guidelines.

Resectable CRC recurrences are rarely detected at colonoscopic surveillance. Surveillance colonoscopies are -performed too frequently and release of NHMRC guidelines has failed to change practice.