Narrow-band imaging bests Lugol for diagnosis of early SCC, finds study

Narrow-band imaging (NBI) is as sensitive as Lugol chromoendoscopy to detect esophageal squamous cell carcinoma (SCC) but its specificity, which appears higher than that of Lugol chromoendoscopy in expert centers, remains to be established in general practice. Previous studies by Ishihara et al. demonstrated lower sensitivity of narrow band imaging (NBI) when compared to chromoscopy with Lugol's solution among inexperienced endoscopists, with an increase over the course of the study. For experienced endoscopists, sensitivity levels were consistent between the two methods . In yet another study ,Yokoyama et al. showed that NBI without magnification is suitable for esophageal assessment when searching for a neoplasm in a high-risk population, even without high-definition imagery . With such a controversial background,this study aimed to prove the superiority of NBI specificity over Lugol chromoendoscopy in the detection of esophageal SCC and high grade dysplasia (HGD) in current general practice (including tertiary care centers, local hospitals, and private clinics).

This prospective randomized multicenter trial included consecutive patients with previous or current SCC of the upper aerodigestive tract who were scheduled for gastroscopy. Patients were randomly allocated to either the Lugol or NBI group. In the Lugol group, examination with white light and Lugol chromoendoscopy were successively performed. In the NBI group, NBI examination was performed after white-light endoscopy. We compared the diagnostic characteristics of NBI and Lugol chromoendoscopy in a per-patient analysis.

Results put forth some key facts.

• 334 patients with history of SCC were included and analyzed (intention-to-treat) from 15 French institutions between March 2011 and December 2015.
• In per-patient analysis, sensitivity, specificity, positive and negative likelihood values were 100 %, 66.0 %, 21.2 %, and 100 %, respectively, for Lugol chromoendoscopy vs. 100 %, 79.9 %, 37.5 %, and 100 %, respectively, for NBI. Specificity was greater with NBI than with Lugol (P = 0.002).

For full article follow the link: DOI: 10.1055/a-1224-6822

Source: Endoscopy