The high yield of 1-year colonoscopy after resection: is it the handoff?

This study aimed to determine the diagnostic yield of colonoscopy 1 year after colorectal cancer (CRC) resection based on whether the index colonoscopy was performed by the operating surgeon.

All patients undergoing surgery for colorectal cancer by two colon and rectal surgeons at a university hospital from 1991 to 2005 were identified from the tumor registry. Those patients with a complete preoperative colonoscopy by any physician and a 1-year follow-up examination by the operating surgeon were selected for the study population. Family history of colorectal cancer, tumor location, endoscopist, presence of synchronous neoplasms, and findings of 1-year colonoscopy were recorded. Fisher's exact test was used to compare the probability of finding any adenoma, advanced adenoma, or invasive cancer based on the index endoscopist.

Of the 719 patients who underwent resection during the study period, 432 met the inclusion criteria. The index colonoscopy for 117 of these patients (27.1%) was performed by one of the two surgeons. Overall, 10 patients (2.3%) had a "new" cancer diagnosed at 1 year, and 1 patient (0.2%) had a local recurrence. Patients whose index colonoscopy was performed by their operating surgeon appeared less likely to have an advanced lesion found at 1 year (5.1% vs 11.4%; p = 0.06). The index colonoscopy for 9 of the 10 of cancers found at 1 year was not performed by the operating surgeon.

Colonoscopy 1 year after CRC resection is clearly justified. An index colonoscopy by the operating surgeon eliminates a "handoff" and may diminish the incidence of high-risk lesions at 1 year.