Achieving negative superficial resection margins with NBI and white light in carcinoma oral cavity: Could it be a norm?

Introduction: In India, oral cavity cancer rates are the highest, largely due to tobacco and areca nut use. The primary goal of oncologic surgery is complete tumor resection with adequate margins, yet no accepted guidelines exist margin identification. NBI enhances mucosal lesion detection and may improve margin assessment in OSCC.

Aims: This study aims to evaluate the proportion of negative superficial resection margins using NBI and to compare these results with margins assessed using white light (WL) examination.

Materials And Methods: The study at AIIMS, Rishikesh, included 38 patients with T1-T3 biopsy-proven OSCC. Surgical margins were marked using WL and NBI. Histopathology classified margins as clear (>5mm), close (1-5 mm), or involved. Sensitivity, specificity, and predictive values of NBI were calculated.

Results: The average NBI examination duration was 227 s. Negative margins were achieved in 68.42 % (>5mm) and 78.94 % (>3mm) of NBI cases, compared to 71.05 % and 84.21 % for WL. NBI had a sensitivity of 12.50 %, specificity of 96.67 %, and overall accuracy of 78.95 %.

Discussion: NBI showed high specificity but low sensitivity. This could be due to the smaller number of patients in NBI positive group. In the present study, the single positive margin identified with NBI could also have been detected with the combined approach of white light and palpation, ensuring that no positive margins were missed.

Conclusion: NBI can complement WL for margin assessment in oral SCC but requires a long learning curve and a dedicated team. Integrating NBI into standard protocols could improve surgical outcomes and reduce recurrence.