Narrow band imaging as screening test for early detection of laryngeal cancer: a prospective study

Objectives: To analyse the specificity and sensibility of narrow band imaging illumination technology in the early detection of laryngeal cancer in the patients’ population without previous diagnosis of laryngeal cancer in a screening setting. Design: Unicentre, prospective study. Setting: One tertiary medical centre. Participants: A total of 158 patients completed all protocol steps. Main outcome measures: Sensitivity, specificity, positive and negative predictive values of narrow band imaging (NBI) in detecting precancerous lesions and early laryngeal cancer. Results: The blind assessment of NBI patterns concurred in 90% of patients. In identifying laryngeal cancer and its precursor lesions, in-office NBI showed a high sensitivity of 97% (CI, 84.2%–99.9%), specificity of 92.5% (CI, 79.6%–98.4%), PPV of 91.4% (CI, 76.9%–98.2%), NPV of 97.4% (CI, 86.2%–99.9%) and accuracy of 94.5% but intra-operative NBI demonstrated a sensitivity of 97% (CI, 84.2%–99.9%), a slightly higher specificity of 95% (CI, 83.1%–99.4%), PPV of 94.1% (CI, 80.3%–993%), NPV of 97.4% (CI, 86.5%–99.9%) and accuracy of 95.9%. The comparative receiver operating characteristic curves confirmed a slightly higher performance for the intra-operative NBI evaluation without any statistical significance (P = 0.41). Conclusions: Our results confirm the high values of sensitivity and specificity of NBI system in detecting pre-neoplastic laryngeal lesions or early laryngeal cancer in a patients’ population selected only by means of risk factors exposure and confirmed the potential role of NBI evaluation as in-office screening tool.