4 Questions About Detecting Intestinal Metaplasia

Results of a recent study¹ suggest that the wide-area transepithelial sampling (WATS) brush is superior to biopsies in detecting intestinal metaplasia among patients without a history of intestinal metaplasia.

These conclusions come after 1002 patients presenting for upper endoscopy for foregut symptoms or Barrett esophagus were randomly assigned to receive a biopsy or WATS brush. Patients with a history of malignancy were excluded.

To find out more about these results, Gastroenterology Consultant reached out to lead author Steven DeMeester, MD, who is a surgeon in the Gastrointestinal & Minimally Invasive Surgery group at the Oregon Clinic in Portland, Oregon.

GASTRO CON: What prompted you to conduct the study?

Steve DeMeester: The WATS brush has intrigued me for quite a period of time, because the technology behind it is really novel and offers the opportunity to be a game-changer. But the use of it was always in addition to biopsies.

The problem with extensive biopsies—which are necessary for patients with Barrett esophagus—is it is time-consuming, and it is not paid for by insurance companies. Nobody is excited about taking 20 minutes to do a Seattle biopsy protocol and then add a WATS on top of it. It is not a situation that is going to be adopted by many people.

The concept from the beginning for me was to find something quicker than the Seattle biopsy protocol that is just as reliable. For me, it was always the WATS brush or biopsies. Finally, we were able to organize a multicenter randomized trial to show that the WATS and biopsies could be used interchangeably, which was the goal of the study.

As it turned out, in some circumstances, the WATS brush is superior. Overall, they are equivalent, though, suggesting that our hypothesis is correct—that we can use WATS instead of biopsies in patients with Barrett esophagus and in patients presenting for routine endoscopy without Barrett esophagus.

GASTRO CON: What is the most important take away from your study for gastroenterologists?

SD: There are 3 important takeaways, actually. First is that the biopsies or WATS can be used interchangeably. If it is a long-segment Barrett esophagus, you can use the WATS brush and not perform biopsies, and not lose any efficacy in detecting intestinal metaplasia or dysplasia.

The next important takeaway is that for short segments of columnar-lined esophagus that 2- or 3-cm segment, the WATS is actually superior to biopsies and should be the preferred approach to sample that short segment to find intestinal metaplasia, since the WATS outperformed biopsies in that area. Likely because, in a short segment, you only take 1 or 2 biopsies and you miss things related to sampling error, whereas the WATS gets a more uniform sampling of that segment.

The third takeaway is that current guidelines from gastroenterology societies suggest that you should ignore anything less than 1 cm of columnar-lined esophagus. There is no scientific basis for that guideline. It was pulled out of the air. In fact, it is almost going backward in time. In the 1960s, Hayward² suggested there was a normal buffer zone of columnar mucosa between the acid-producing stomach and the acid-sensitive esophagus. While it seems logical, in fact it has been disproven. There is no scientific basis for the current guideline, since any visible segment of columnar mucosa in the esophagus is abnormal. What our current study shows is that guideline is misguided.

About 15% of patients have a precancerous condition, called intestinal metaplasia, when there was less than 1 cm of columnar mucosa in the esophagus. Some of those patients had dysplasia and even one cancer. It is not a valid assumption that less than 1-cm columnar-lined esophagus is something that can be safely ignored. That guideline has no scientific basis and is invalidated by our study.

GASTRO CON: Were there any limitations to your study? Did you face any challenges when conducting the study?

SD: I would say that the one factor is that this was a group of patients who were enriched with reflux disease. The majority of these patients were undergoing upper endoscopy for symptoms of reflux disease, many of them presenting to surgical centers for evaluation for possible anti-reflux surgery. Nonetheless, it represents the population of patients—at least a portion of population of the patients—who are out there with reflux disease.

Our study also included patients with known Barrett esophagus and patients who had been ablated or treated for Barrett esophagus. It represents a nice spectrum of the reflux disease population. Although, it may not be representative of the general population with reflux symptoms.

GASTRO CON: What are the next steps in your research?

SD: The next steps are to further characterize the best techniques to identify intestinal metaplasia and dysplasia so that we can prove that surveillance for Barrett esophagus is effective for identifying early tumors and allowing them to be treated and for patients to have a better outcome.

There is a big debate going on right now about the effectiveness of surveillance for Barrett esophagus. There are 2 components to that. One is that, because it is so time-consuming and difficult, it was not always done well. The second is that guideline intervals are too long. If we make it easier and more reliable to do the biopsies, and we find an effective interval, I have no doubt that we will demonstrate that surveillance for Barrett esophagus is beneficial and saves lives.

There is nothing worse than to have a patient with a known precancerous condition and have ablation technologies that can eradicate dysplasia before it ever becomes cancer, and then have the patient go on to die of esophageal cancer because our surveillance was inadequate.

References:

1. DeMeester S, Smith C, Severson P, Jobe B, Woodworth P, Dunst C. Multi-center randomized trial comparing standard forceps biopsies to wide-area transepithelial sampling brush for finding intestinal metaplasia and dysplasia in the esophagus and gastroesophageal junction. Am J Gastroenterol. 2019;114(Suppl):S207-S208. doi:10.14309/01.ajg.0000590944.34704.3c
2. Hayward J. The lower end of the esophagus. Thorax. 1961;16(1):36-41. https://doi.org/10.1136/thx.16.1.36