Laryngeal dysplasia and narrow band imaging: Secondary analysis of published data supports the role in patient follow-up

Background Clinicians have recognised the role of narrow band imaging (NBI) in the management of head and neck cancer in several studies. However, a recent systematic review was unable to pool the data on diagnostic efficacy in this setting owing to the heterogeneity in the published data. Methods Secondary analysis of data, utilising Bayes' theorem, from meta-analyses and randomised trials. Results In patients with a histological diagnosis of mild dysplasia who show no abnormalities on NBI, the post-test probability of malignancy is estimated to be 2.3%, compared to 10.3% with conventional white light imaging (WLI). For severe dysplasia, similar post-test probabilities after NBI and WLI are estimated to be 8.0% and 29.7%, respectively. Post-test probabilities in this setting indicate the chance of missing malignancy following a negative NBI or WLI in patients who undergo no further intervention. This study also provides a nomogram designed for use in this setting. Conclusions This study identifies the evidence base for use of NBI in the follow-up for laryngeal dysplasia.