The Value of NBI in the Detection of Local Recurrences of Head and Neck Squamous Cell Carcinoma After (Chemo)radiotherapy: A Randomised Controlled Trial

Objectives Detection of local recurrences after (chemo)radiotherapy (C)RT for head and neck squamous cell carcinoma (HNSCC) is challenging due to post‐treatment mucosal changes. This study assessed the added diagnostic value of narrow band imaging (NBI) compared to white light imaging (WLI) during rigid endoscopy under general anaesthesia for recurrence detection. A secondary aim was to assess NBI's ability to detect tumour extension surrounding the suspected carcinoma, which remained undetected by WLI. Design Prospective randomised controlled trial with 1:1 block randomisation. Setting Single tertiary referral centre. Participants Ninety‐four patients with a suspected local recurrence after (C)RT, randomised to WLI ( n = 47) or WLI+NBI ( n = 47). Main Outcome Measures Sensitivity, specificity, predictive values and survival outcomes, with histopathology as reference standard. Results A recurrence was histopathologically confirmed in 36 patients (38%). Surgeons judged lesions as highly suspected of malignancy in 48 patients (51%): 24 (50%) in each group. WLI yielded sensitivity 84.2%, specificity 71.4%, PPV 66.7%, and NPV 87.0%. WLI+NBI showed slightly lower sensitivity (75.0%) and specificity (66.7%), with PPV 62.5% and NPV 78.3%. Identification of Ni type V lesions alone significantly improved specificity, PPV and accuracy. No differences in disease‐specific or overall survival were found between groups. Conclusion In previously irradiated patients, NBI provides marginal additional diagnostic value over WLI in detecting local recurrence of HNSCC. Isolated use of Ni type V as a malignancy marker improves specificity, PPV and accuracy.