Primary Motility  Disorders of the  Esophagus
 The Esophageal
 Mucosa
 The
 Esophagogastric  Junction
 Barrett's
 Esophagus

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OESO©2015
 
Volume: Barrett's Esophagus
Chapter: Screening and surveillance
 

Is regression of short segments Barrett's esophagus likely to occur under treatment?

R.K.H. Wong (Washington)

The prevalence of short segments Barrett's esophagus (SSBE) ranges between 5-36% depending upon how many biopsies of the columnar segment are taken, the type of histologic stain employed, and the length of the tongue biopsied. Patients accessioned into SSBE studies had upper gastrointestinal symptoms requiring endoscopy and were not normal controls. The majority of patients were on some form of acid suppressive agent, mainly H2-receptor antagonists or proton pump inhibitors. None of the long-term studies have standard antisecretory therapy with most patients being treated symptomatically.

The term regression can be viewed in several ways:
- actual movement of columnar epithelium distally either by actual regression of specialized intestinal metaplasia (IM) or by overgrowth of squamous epithelium,
- normalization of the specialized IM to either fundic or cardiac mucosa where biopsies no longer show evidence of goblet cells.

With SSBE, proving linear regression and overgrowth with squamous epithelium is difficult, as the maximal length of a tongue is only 3 cms. Quantitating regression is only possible if:
- tattooing is performed at the upper margin of the tongue and the squamous epithelium has overgrown the tattoo,
- there are no visible tongues,
- or a 3 cm tongue regresses to less than 1 cm.

Normalization of specialized IM to mucosa without goblet cells is the more likely scenario. One can always contend that normalization does not occur in SSBE and that specialized IM was missed. Unless the entire columnar mucosa in question is completely stripped and sectioned for histologic confirmation, this criticism can never be fully addressed. On the other hand, one must remember that more biopsies are usually taken in a relatively small area of SSBE in subsequent follow-up endoscopies and hence it would be less likely to miss specialized IM.

Only 3 studies in the literature have followed SSBE patients overtime and have reported a lack of goblet cells on incident biopsy specimens. In one study by Weston et al. [1], 50% (13/26) of patients with SSBE who underwent multiple esophagogastric diseases and histologic sampling had no evidence of specialized IM. Of these patients, one had no specialized IM on 3 exams and 3 patients had no specialized IM on 2 exams. This was in contrast to the long segment Barrett's esophagus (LSBE) cohort in which few or non of the patients studied showed any normalization to a non-specialized IM histology.

Horwhat et al. [2], noted that 30% (13/44) of SSBE patients underwent normalization over a 3-4 year period. In contradistinction, none of the LSBE patients showed normalization of histology while 67% (23/43) of esophagogastric junction-specialized IM (EGJ-SIM) patients underwent normalization. There was also a slight decrement in the length of Barrett's epithelium of 0.4 cm for SSBE, 1.3 cm for LSBE and a slight increase in length in the columnar length for EGJ-SIM.

After 9 months of intensive acid suppression (pH > 4, as documented by 24 hour-pH monitoring), Hirota et al. [3] noted a 42% (5/12) normalization of SSBE (n = 8) and EGJSIM (n = 4) tissue.

These data suggest that normalization and possibly regression of SSBE may occur with treatment over time. This data is also consistent with the pathophysiology of these disease processes. With LSBE there is extensive, prolonged acid exposure in the esophagus and a higher degree of dysplasia, cancer and molecular gene alterations. In SSBE, acid exposure is not as prolonged and the prevalence of dysplasia and cancer is significantly lower. With possible fewer gene alterations in the SSBE mucosa, the specialized IM in SSBE and EGJSIM may be more reversible with acid suppressive therapy.

References

1. Weston AP, Krmpotich PT, Cherian R, Dixon A, Topalosvki M. Prospective long-term endoscopic and histological follow-up of short segment Barrett's esophagus: comparison with traditional long segment Barrett's esophagus. Am J Gastroenterol 1997;92:407-413.

2. Horwhat JD, Baroni D, Maydonovitch C, Osgard EM, Ormseth EJ, Rueda-Pedraza, E, Yang H, Hirota W, Wong RKH. The incidence of regression and normalization of intestinal metaplasia in a cohort of patients with EGJ-SIM, SSBE and LSBE followed over

3. years. Gastroenterology 2000;118(4):A1350. 3. Hirota WK, Loughney TM, Lazas DJ, Maydonovitch CL, Rholl V, Wong RKH. Short segment Barrett's esophagus and specialized intestinal metaplasia at the esophagogastric junction: serial endoscopic and histologic assessment after acid suppression with omeprazole. Gastroenterology 1997;112(4) A577.


Publication date: August 2003 OESO©2015