Narrow-Band Imaging versus Lugol chromoendoscopy for esophageal squamous cell cancer screening in normal endoscopic practice: randomized controlled trial.

OBJECTIVE Narrow-Band Imaging (NBI) is as sensitive as Lugol chromoendoscopy to detect oesophageal squamous cell carcinoma (SCC) but its specificity, which appears higher than than that of Lugol chromoendoscopy in expert centres, remains to be established in current practice. This study aimed to prove the superiority of NBI specificity over Lugol chromoendoscopy in the detection of oesophageal SCC and high-grade dysplasia (HGD) in current practice (including tertiary care centres, local hospitals, and private clinics). TRIAL DESIGN Prospective randomised multicentre trial including consecutive patients with previous or current SCC of the upper aerodigestive tract addressed for gastroscopy. Patients included 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 exam was performed after white light endoscopy. We compared the diagnostic characteristics of NBI and Lugol chromoendoscopy in a per-patient analysis. RESULTS 334 patients with previous history of SCC were included and analysed in intention-to-tret from 15 French institutions between March 2011 and December 2015. In a per-patient analysis, sensitivity, specificity, positive and negative likelihood values were respectively 100%, 66.0%, 21.2%, and 100% for Lugol chromoendoscopy vs. 100%, 79.9%, 37.5%, and 100% for NBI. NBI specificity was greater than Lugol chromoendoscopy (p=0.0023). CONCLUSIONS As previously demonstrated in expert centres, NBI is more specific than Lugol in current gastroenterology practice for the detection of early SCC but combined approaches with both NBI and lugol could improve the detection of squamous neoplasia.