How Accurate Is Preoperative Colonoscopic Localization of Colorectal Neoplasms?

Laura Fernandez, MD, Rowaa N Ibrahim, MD, Ido Mizrahi, MD, Giovanna DaSilva, MD, Steven D Wexner, MD. Cleveland Clinic Florida, Weston, FL

INTRODUCTION: Pre-operative colonoscopic localization with or without tattoo as a guide for resection has been extensively used with variable accuracy. Difficulty in intraoperative identification of the lesion may lead to resection of an incorrect segment or to more extensive resection than originally planned. The aim of this study was to evaluate the accuracy of preoperative colonoscopy in determining the site of the lesion.

METHODS: A prospectively maintained IRB-approved institutional database was retrospectively queried for all consecutive patients who underwent an elective colon resection for neoplasia between 2013-2016.Excluded were patients without preoperative colonoscopy reports available for comparison or who underwent emergency surgery. Surgical plan based on pre-operative colonoscopic localization with or without tattoo was compared to the final surgery and pathology reports.

RESULTS: 203 patients were identified, 34 (16.7%) of whom had a change in their surgical plan due to inaccurate pre-operative colonoscopic localization. Patients with transverse or distal lesions were more likely to have a change in final surgical management compared to proximal sided lesions (29.7% vs 3.9%, respectively; p<0.001). In addition, patients who had undergone preoperative endoscopic tattooing of the primary lesion were more likely to have a change in final surgical management than were patients without tattooing (22.9 vs 5.5%, respectively; p<0.001). Only 3.8% of the tattoo ink could not be identified during surgery. Intraoperative colonoscopy was needed in 11 patients (5.5%) to verify lesion location. The average length of the resected segment was longer in patients who required a change in surgical plan (26.44cm vs 22.47cm;p=0.02) (see table).

CONCLUSIONS: Inaccurate pre-operative colonoscopic localization led to a change in surgical management in 16.7% of cases. Factors associated with intraoperative change in surgical management include transverse or left sided lesions and tattooing. Surgeons should consider these findings when planning colonic resections.