Finding the needles in the haystack

Prospective, controlled tandem endoscopy study of narrow band imaging for dysplasia detection in Barrett's Esophagus

BACKGROUND & AIMS

High-resolution endoscopy with narrow band imaging (NBI) enhances the visualization of mucosal glandular and vascular structures. This study assessed whether narrow band targeted biopsies could detect advanced dysplasia using fewer biopsy samples compared with standard resolution endoscopy.

METHODS

We conducted a prospective, blinded, tandem endoscopy study in a tertiary care center with 65 patients with Barrett's esophagus undergoing evaluation for previously detected dysplasia. Standard resolution endoscopy was used first to detect visible lesions. Narrow band endoscopy was then used by another gastroenterologist to detect and biopsy areas suspicious for dysplasia. The lesions initially detected by standard resolution endoscopy were then disclosed and biopsied, after biopsy of the lesions targeted with NBI. Finally, random 4-quadrant biopsies were taken throughout the segment of Barrett's mucosa.

RESULTS

Higher grades of dysplasia were found by NBI in 12 patients (18%), compared with no cases (0%) in whom standard resolution white light endoscopy with random biopsy detected a higher grade of histology (P < .001). Correspondingly, narrow band directed biopsies detected dysplasia in more patients (n = 37; 57%) compared with biopsies taken using standard resolution endoscopy (n = 28; 43%). In addition, more biopsies were taken using standard resolution endoscopy with random biopsy compared with narrow band targeted biopsies (mean 8.5 versus 4.7; P < .001).

CONCLUSIONS

In patients evaluated for Barrett's esophagus with dysplasia, NBI detected significantly more patients with dysplasia and higher grades of dysplasia with fewer biopsy samples compared with standard resolution endoscopy.

The detection, surveillance and treatment of premalignant gastric lesions related to Helicobacter pylori infection

Gastric cancer is an important worldwide health problem and causes considerable morbidity and mortality. It represents the second leading cause of cancer-related death worldwide. A cascade of recognizable precursor lesions precedes most distal gastric carcinomas. In this multistep model of gastric carcinogenesis, Helicobacter pylori causes chronic active inflammation of the gastric mucosa, which slowly progresses through the premalignant stages of atrophic gastritis, intestinal metaplasia and dysplasia to gastric carcinoma. Detection and treatment of premalignant lesions may thus provide a basis for gastric cancer prevention. However, at present, premalignant changes of the gastric mucosa are frequently disregarded in clinical practice or result in widely varying follow-up frequency or treatment. This review provides an overview of current knowledge on detection, surveillance and treatment of patients with premalignant gastric lesions, and identifies the uncertainties that require further research.