Does narrow band imaging improve preoperative detection of glottic malignancy? A matched comparison study.

Objectives/hypothesis: The primary suspicion for glottic malignancy during office laryngoendoscopy is based on lesion appearance. Previous studies investigating laryngeal use of narrow band imaging (NBI) are mostly descriptive. The additive value of NBI relative to white light (WL) requires further investigation.

Study Design: Observational matched study.

Methods: NBI was compared with WL images of 45 vocal fold lesions suspected for malignancy (21 carcinoma, 22 dysplasia, two benign). All images were presented randomly and evaluated by six independent otolaryngology specialists. The observers were asked to estimate lesion size, location, and pathology. The results for the two imaging modalities were compared with each other and with the final pathology.

Results: The observers estimated lesion size to be larger in the NBI images by an average of 9% (2.4 mm ; P =.04) compared to WL. In 64.6% of cases, the observers estimated similar pathology for NBI and WL. When there was a discrepancy, the estimated pathology was "malignant" in 24.3% by NBI, compared with 11.1% by WL. Overall, 44.7% of the lesions were estimated to be malignant by NBI, compared with 33.8% by WL (P =.001). The sensitivity and specificity rates for malignancy detection by NBI were 58.6% and 61.2%, respectively, compared to 48.7% and 76.1% by WL.

Conclusions: Observers tend to estimate vocal fold lesions to be larger and more frequently suspect malignancy while assessing NBI images. Compared with WL, NBI demonstrates increased sensitivity and decreased specificity for detection of malignancy. Nevertheless, the specificity and sensitivity of NBI alone are considerably low.

Level Of Evidence: 4 Laryngoscope, 127:894-899, 2017.