Fluorescence imaging for the detection of early neoplasia in Barrett's esophagus: old looks or new vision?

Early neoplasia arising from Barrett's esophagus is often small, focally distributed and endoscopically poorly visible, and random four-quandrant biopsies may easily miss early lesions. Advanced imaging techniques, such as (auto)fluorescence-based modalities, aim to increase the detection rate of early lesions or the yield of random biopsies. Fluorescence-based light-tissue interaction has been designed successfully in point-probe differentiating spectroscopy systems or integrated into wide-field endoscopic systems such as autofluorescence imaging (AFI). In this review, we discuss the most recent advances in fluorescence spectroscopy and imaging for detecting early Barrett's neoplasia. A spectroscopy probe, integrated into regular biopsy forceps, was shown to offer decent discriminatory capabilities, while ensuring spot-on correlation between the measured area and the corresponding histology. With this tool, surveillance endoscopy with random biopsies may become more efficient and sensitive. AFI was shown to increase the targeted detection of early neoplasia. However, random biopsies could compensate for this effect. The clinical impact of AFI on the diagnosis and the treatment of early neoplasia is limited, and yet AFI may offer a novel approach in biomarker-based risk-stratification models. Moreover, in combination with new, readily available contrast agents such as fluorescent lectins, fluorescence imaging may receive renewed interest.

Randomized crossover study comparing efficacy of transnasal endoscopy with that of standard endoscopy to detect Barrett's esophagus.

BACKGROUND: Unsedated transnasal endoscopy (TNE) may be safer and less expensive than standard endoscopy (SE) for detecting Barrett's esophagus (BE). Emerging technologies require robust evaluation before routine use. OBJECTIVE: To evaluate the sensitivity, specificity, and acceptability of TNE in diagnosing BE compared with those of SE. DESIGN: Prospective, randomized, crossover study. SETTING: Single, tertiary-care referral center. PATIENTS: This study enrolled consecutive patients with BE or those referred for diagnostic assessment. INTERVENTION: All patients underwent TNE followed by SE or the reverse. Spielberger State-Trait Anxiety Inventory short-form questionnaires, a visual analogue scale, and a single question addressing preference for endoscopy type were administered. MAIN OUTCOME MEASUREMENTS: Diagnostic accuracy and tolerability of TNE were compared with those of SE. RESULTS: Of 95 patients randomized, 82 completed the study. We correctly diagnosed 48 of 49 BE cases by TNE for endoscopic findings of columnar lined esophagus compared with the criterion standard, SE, giving a sensitivity and specificity of 0.98 and 1.00, respectively. The BE median length was 3 cm (interquartile range [IQR] 1-5 cm) with SE and 3 cm (IQR 2-4 cm) with TNE, giving high correlations between the two modalities (R(2) = 0.97; P < .001). The sensitivity and specificity for detecting intestinal metaplasia by TNE compared with those by SE was 0.91 and 1.00, respectively. The mean (± standard deviation) post-endoscopy Spielberger State-Trait Anxiety Inventory short-form score for TNE (30.0 ± 1.10 standard error of the mean [SEM]) was lower than that for SE (30.7 ± 1.29 SEM), (P = .054). The visual analogue scale scores were no different (P = .07). The majority of patients (59%) expressed a preference for TNE. LIMITATIONS: This is a small study, with limited generalizability, a high prevalence of patients with BE, differential drop-out between the two procedures, and use of sedation. CONCLUSION: TNE is an accurate and well-tolerated method for diagnosing BE compared with SE. TNE warrants further evaluation as a screening tool for BE.