The Role of the Narrow Band Imaging for Lung Cancer

폐암에서의 협대역 내시경의 역할

The proliferation of new technologies has significantly enhanced the diagnostic capabilities of flexible bronchoscopy compared with traditional methods. Narrow band imaging (NBI), an optical technique in which filtered light enhances superficial neoplasms based on their neoangiogenic patterns, was developed to screen for central intraepithelial moderate or severe dysplasia, carcinoma in situ (CIS), and microinvasive neoplasia in patients at risk for lung cancer. Because angiogenesis occurs preferentially in dysplastic and neoplastic lesions, NBI may identify early dysplastic lesions better than white light bronchoscopy (WLB) currently in use. NBI bronchoscopy can be used not only to detect precancerous lesions, but also to screen for cancerous lesions. We prospectively evaluated 101 patients with suspected lung cancer between July 2009 and June 2010. All were previously scheduled for flexible bronchoscopy CT scans. Abnormal NBI was defined by Shibuya's descriptors (tortuous, dotted, or spiral and screw patterns). Biopsies of 132 lesions in 92 patients showed that 78 lesions (59.1%) were malignant and 54 (40.9%) were benign. The diagnostic sensitivity of bronchoscopy in detecting malignancy was 96.2% (75/78). When assorted by lesion pattern, the sensitivity and specificity of NBI bronchoscopy in detecting malignancies were 69.2% (54/78) and 96.3% (52/54), respectively, for the spiral and screw pattern and 14.1% (11/78) and 96.3% (52/54), respectively, for the dotted pattern. Unexpectedly, additional cancerous lesions were detected in five patients (2 dotted and 3 spiral and screw). As a screening tool for malignant lesions, NBI bronchoscopy should assess combinations of all three lesion. The dotted and spiral and screw patterns may be helpful in determining which lesions should be biopsied. NBI bronchoscopy may be useful not only for the diagnosis of early-stage lung cancer but also for more accurate local staging of lung cancer.