Evaluating hypopharyngeal carcinoma using narrow band imaging and oxygen-injected laryngoscope: New technique

To evaluate the diagnostic value of narrow band imaging (NBI) endoscopic classification for hypopharyngeal lesions and to lay the groundwork for practical applications of oxygen-injected laryngoscope for hypopharyngeal carcinoma (HC).

A total of 140 subjects with suspected 146 hypopharyngeal lesions were selected for pathological examination. Subsequently, NBI and white light imaging (WLI) endoscopy were performed to observe and classify lesions into 7 types according to our modified NBI classification. Pathological results were used as the gold standard to assess the diagnostic value of the NBI classification. The value of oxygen-injected laryngoscope for accurate assessment of lesion extension was evaluated based on the exposure of hypopharyngeal lesions before and after use.

The accuracy, sensitivity, and negative predictive value of NBI endoscopy in diagnosing hypopharyngeal lesions were 95.9 %, 96.7 %, and 84.6 %, respectively, which were higher than those of WLI mode (p < 0.05). NBI endoscopy was more accurate than WLI in diagnosing malignant lesions (p < 0.05), especially for high-grade dysplasia (HGD) (p < 0.05). There was remarkable consistency between NBI classification and pathological results (Kappa = 0.855). Type Va and type Vb-c accounted for 72.7 % and 92.8 % of HGD and invasive carcinoma, respectively. Moreover, the oxygen-injected laryngoscope was found to provide a more accurate assessment of HC extension (P < 0.001).

We propose a more appropriate NBI endoscopic classification for hypopharyngeal lesions, which can effectively improve diagnostic accuracy, especially for the early diagnosis of hypopharyngeal cancer. Moreover, the application of oxygen-injected laryngoscope is essential for the accurate assessment of HC and has a high clinical utility.