Regional center for complex colonoscopy: yield of neoplasia in patients with prior incomplete colonoscopy

Incomplete colonoscopy increases the risk of incident proximal colon cancer postcolonoscopy. Incomplete colonoscopy is often followed by barium enema or CT colonography. We sought to describe the yield of completion colonoscopy in a regional center for complex colonoscopy.

This is a retrospective cohort study of 520 consecutive patients referred to a single colonoscopist over a 14-year period for completion colonoscopy after a previous incomplete examination.

Colonoscopy was completed to the cecum in 506 of 520 patients (97.3%). A total of 913 conventional adenomas was removed in 277 patients (adenoma detection rate 53.3%). There were 184 adenomas ≥ 1 cm in size or with advanced pathology. There were 525 serrated-class lesions removed in 175 patients, including 54 sessile serrated polyps in 26 patients and 41 hyperplastic polyps greater than 1 cm in 26 patients. Nine colorectal cancers were found. We estimated that approximately 57% of the conventional adenomas, 58% of the sessile serrated polyps, 27% of the hyperplastic polyps, and all 9 cancers detected by the completion colonoscopy were beyond the extent of the previous examination.

The yield of completion colonoscopy in a cohort of patients with previous failed cecal intubation was substantial. Regional centers for complex colonoscopy can provide high rates of cecal intubation in cases of incomplete colonoscopy and high yields of lesions in these cases. The regional center for complex colonoscopy is an important medical service.