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.