Screening for Barrett's Esophagus

Abstract

The large increase in the incidence of esophageal adenocarcinoma in the West during the past 30 years has stimulated interest in screening for Barrett's esophagus (BE), a precursor to esophageal cancer. Effective endoscopic treatments for dysplasia and intramucosal cancer, coupled with screening programs to detect BE, could help reverse the increase in the incidence of esophageal cancer. However, there are no accurate, cost-effective, minimally invasive techniques available to screen for BE, reducing the enthusiasm of gastroenterologists. Over the past 5 years, there has been significant progress in the development of screening technologies. We review existing and developing technologies, new minimally invasive imaging techniques, nonendoscopic devices for cell collection, and biomarkers that can be measured in blood or stool samples. We discuss the status of these approaches, data from clinical studies of their effects, and their anticipated strengths and weaknesses in screening. The area is rapidly evolving, and new tools will soon be ready for prime time.

Keywords: Biomarkers; Biophotonics; Cytology; Endoscopy; FISH.

Figure 1

Three cases of BE imaged with 3 different types of TNE systems (left panel), with a corresponding picture taken with a conventional white light Olympus system (right panel images). (Top left panel, Pentax TNE; middle left panel, office-based EndoSheath; bottom left panel, office-based EG scan).

Figure 2

Examples of VLE. (A) A VLE circular scan with imaging of the multilayered squamous esophagus and identification of the layered structure. Sections of the scan can be expanded in the device. It is apparent that this resolution is superior than can be seen with even the highest-resolution endoscopic ultrasound probes. (B) Sector magnification of VLE shows a mucosa without a great degree of surface scattering, indicating a likelihood of nondysplastic BE. The glands indicated by the arrowheads suggest the presence of an abnormal submucosal microenvironment.

Figure 3

Layered epithelium in the cross sectional view on the left with a much enhanced sector view on the right showing the individual layers of the squamous mucosa.

Figure 4

Use of the Cytosponge. (A) Cytosponge embedded in a gelatin capsule. (B) The Cytosponge is swallowed and descends to the stomach through the esophagus. (C) The expanded Cytosponge. (D) The Cytosponge is retrieved by an assistant who pulls the string. (E) Immunohistochemical analysis of TTF3 in cells collected by the Cytosponge as well as BE cells (arrows).