Introduction: One of the most recent methods used in imaging of the larynx is narrow band imaging (NBI). NBI enables us to detect specific patterns of pathological angiogenesis suggestive of premalignant or neoplastic lesions. The aim of the study was to compare imaging of laryngeal lesions in white light endoscopy (WLE) and NBI in relation to histopathological examination.
Material and methods: 333 patients with laryngeal lesions underwent endoscopic evaluation in WLE and NBI. Sensitivity, specificity, positive and negative predictive value (PPV, NPV) for WLE and NBI were calculated. The diagnostic value for WLE and NBI was evaluated for two assumptions (positive result is:1. severe dysplasia and cancer 2. only cancer) Results: Sensitivity, specificity, PPV, NPV of first assumption were respectively for white light compared to NBI: 95.4% vs 98.5%; 84.2% vs 98.5%; 79.6% vs 97.7% and 96.6% vs 99.0%. The values of second assumption were: 97.4% vs 100%; 79.3% vs 93.5%; 72.6% vs. 89.4% and 98.2% vs. 100.0%. Higher sensitivity was observed for the second assumption, while higher specifity was recorded for the first assumption. Specificity was significantly higher for NBI than for WLE (p<0.001).
Conclusions: NBI enables us to detect and differentiate laryngeal lesions, which are invisible in WLE. Endoscopic examination, especially in NBI-mode, is non-invasive, repeatable and remains a useful tool in the daily practice and diagnosis of patients with pathological lesions in the larynx.
Keywords: laryngeal cancer; narrow band imaging; premalignant laryngeal lesions; white light endoscopy.