Endocytoscopic visualization of squamous cell islands within Barrett's epithelium

Abstract

Aim: To study the endocytoscopic visualization of squamous cell islands within Barrett's epithelium.

Methods: Endocytoscopy (ECS) has been studied in the surveillance of Barrett's esophagus, with controversial results. In initial studies, however, a soft catheter type endocytoscope was used, while only methylene blue dye was used for the staining of Barrett's mucosa. Integrated type endocytoscopes (GIF-Q260 EC, Olympus Corp, Tokyo, Japan) have been recently developed, with the incorporation of a high-power magnifying endocytoscope into a standard endoscope together with narrow-band imaging (NBI). Moreover, double staining with a mixture of 0.05% crystal violet and 0.1% of methylene blue (CM) during ECS enables higher quality images comparable to conventional hematoxylin eosin histopathological images.

Results: In vivo endocytoscopic visualization of papillary squamous cell islands within glandular Barrett's epithelium in a patient with long-segment Barrett's esophagus is reported. Conventional white light endoscopy showed typical long-segment Barrett's esophagus, with small squamous cell islands within normal Barrett's mucosa, which were better visualized by NBI endoscopy. ECS after double CM staining showed regular Barrett's esophagus, while higher magnification (× 480) revealed the orifices of glandular structures better. Furthermore, typical squamous cell papillary protrusion, classified as endocytoscopic atypia classification (ECA) 2 according to ECA, was identified within regular glandular Barrett's mucosa. Histological examination of biopsies taken from the same area showed squamous epithelium within glandular Barrett's mucosa, corresponding well to endocytoscopic findings.

Conclusion: To our knowledge, this is the first report of in vivo visualization of esophageal papillary squamous cell islands surrounded by glandular Barrett's epithelium.

Keywords: Barrett’s esophagus; Crystal violet; Endocytoscopic atypia classification; Endocytoscopy; Hematoxylin eosin stain; Methylene blue; Surveillance.

Figure 1

White light endoscopy, narrow-band imaging and endocytoscopy examination of long segment Barrett’s esophagus. A: Long segment Barrett’s esophagus under white light endoscopy (WLE); B: Narrow-band imaging with low magnification clearly visualized small squamous cell islands within regular columnar Barrett's epithelium, which are also identified by WLE with difficulty; C: Endocytoscopy (ECS) examination after crystal violet and methylene blue (CM) double staining; D: ECS examination under higher magnification (× 480) shows the glandular orifices of regular Barrett’s epithelium.

Figure 2

Endocytoscopy examination of histologically confirmed squamous cell islands within Barrett’s esophagus. A: Endocytoscopy (ECS) examination shows squamous cell islands, within regular glandular structures of Barrett’s esophagus. According to ECS examination, squamous papillary structure is classified as ECA2, (round-shaped cells with different-sized small nuclei, suggestive of inflammatory changes); B: Histological examination (hematoxylin and eosin stain magnification) of biopsies from the same area as in Figure (A) confirmed the presence of a squamous papillary structure surrounded by Barrett’s glandular epithelium.