Utility of Narrow-Band Imaging during Intraoperative Colonoscopy for Colon Tumor Localization: A Report of Two Cases.

Abstract

Introduction: Accurate intraoperative localization of colonic tumors is essential to ensure appropriate resection margins, particularly in laparoscopic surgery where tactile feedback is limited. Intraoperative colonoscopy combined with narrow-band imaging (NBI) may facilitate precise delineation of tumor borders, but its clinical utility remains underreported.

Case presentation: We report 2 cases of cecal tumors in which intraoperative colonoscopy with NBI was employed to identify tumor margins and guide resection. The first case was a 79-year-old man with a positive fecal occult blood test, in whom colonoscopy revealed a 25-mm laterally spreading tumor (LST) in the cecum. During laparoscopic surgery, intraoperative colonoscopy with NBI clearly visualized the lesion, enabling cecal resection with negative histopathological margins. The second case was a 75-year-old woman referred for surgery following the detection of a 30-mm LST involving the appendiceal orifice. Intraoperative colonoscopy with NBI enabled accurate margin assessment, and the tumor was resected without residual disease. Histopathology confirmed tubulovillous adenoma with negative resection margins.

Conclusions: Intraoperative colonoscopy with NBI was effective for identifying tumor borders and ensuring adequate resection margins in both cases. This approach may be a valuable adjunct in selected patients undergoing laparoscopic colorectal surgery, particularly for tumors located in anatomically complex regions such as the cecum or appendiceal orifice.