Comparison of Diagnostic Potential of Narrow Band Imaging Bronchoscopy Over White Light Bronchoscopy in Lung Cancer

Background: Worldwide, lung cancer is the largest contributor to new cancer diagnoses and to death from cancer. Narrow band imaging (NBI) is a novel bronchoscopic technique which enables detailed examination of submucosal microcapillary grid and showed great potential in early detection of malignant lesions of the bronchial mucosa. The aim of this study was to compare diagnostic potential of NBI bronchoscopy over white light (WL) bronchoscopy in lung cancer. Methods: We enrolled 187 patients having clinical and radiologic findings highly suspicious of lung cancer. Patients were further divided into 2 groups: NBI group (n=102), and control WL group (n=85). Bronchoscopy examination was performed with respective visualization modes and all pathologic lesions were biopsied and histologically confirmed. Results: On NBI bronchoscopy, malignancy was suspected in 69 patients, of whom 62 had malignancy, and 33 patients were suspected of inflammation, of whom 32 had inflammation and only 1 patient had malignancy. Under WL bronchoscopy, 54 patients were suspected of malignancy, of whom 36 had malignancy, and 31 patients were suspected of inflammation, of whom 23 had inflammatory disease and 8 had malignancy. NBI bronchoscopy had sensitivity 98.1%, specificity 82.05%, positive predictive value 89.86% and negative predictive value 96.97% in comparison to standard WL bronchoscopy which had sensitivity 81.82%, specificity 56.10%, positive predictive value 66.67% and negative predictive value 74.19%. Conclusion: NBI bronchoscopy demonstrated better results in comparison to WL bronchoscopy. The presence of pathologic vascularization of the tumor helps to better identify the malignant process. Inflammatory changes in the mucosa can be easily differentiated from malignant changes by the appearance of vessels.