SAN ANTONIO – A wide-area transepithelial sampling (WATS) brush proved superior to standard forceps biopsies for detection of intestinal metaplasia (IM) in the esophagus and gastroesophageal junction in patients with no history of IM who had any visible columnar-lined esophagus on upper endoscopy in a large randomized trial.
“This suggests that WATS should in fact be the preferred method of sampling these patients,”, commented in presenting the study results at the annual meeting of the American College of Gastroenterology.
With that specific exception, however, the two sampling methods proved similarly effective at detecting IM and dysplasia, suggesting either technology can otherwise reliably be used to detect these conditions, added Dr. DeMeester, a general and thoracic surgeon at the Oregon Clinic, Portland.
This is important new information for clinicians. A prior multicenter, randomized trial by other investigators demonstrated that adding WATS to biopsy sampling improved the detection rate of dysplasia and esophageal adenocarcinoma, compared with biopsies alone (). However, this dual-sampling strategy is too time-consuming for routine use in a busy practice. Given the new evidence that the two sampling methods can reliably be used interchangeably except in patients with no history of IM who have endoscopically visible columnar-lined esophagus, WATS offers a clear advantage in that it’s much quicker, especially in patients with long-segment Barrett’s esophagus, the surgeon said.
Unlike brush cytology, which merely collects surface epithelial cells, the WATS brush collects sheets of esophageal mucosa, which then undergo computer-assisted three-dimensional analysis.
“When done appropriately, a wide area of the esophageal mucosa can be sampled with the WATS brush,” Dr. DeMeester explained.
He reported on 1,002 patients who presented at nine U.S. centers for upper endoscopy for Barrett’s esophagus surveillance or evaluation of foregut symptoms. They were randomized to WATS or forceps biopsies using the Seattle protocol. In the entire group, WATS and forceps biopsies were similarly effective, each finding IM – a potentially premalignant mucosal change – in about 21% of patients, and dysplasia or cancer in 0.8%. Among the 185 patients who underwent endoscopy for follow-up of Barrett’s esophagus or post ablation, the two sampling strategies also performed similarly, detecting IM in roughly 36% of the 151 patients with columnar-lined esophagus shorter than 3 cm and in 56% of those with columnar-lined esophagus of greater length.
However, in the 196 patients with no history of IM who had any length of visible columnar-lined esophagus on endoscopy, the frequency of IM detection was 32.7% with WATS, compared with 15.3% with biopsy.
Dr. DeMeester and coinvestigators were also eager to identify factors associated with detection of IM in the esophagus or gastroesophageal junction in patients undergoing elective endoscopy with no history of IM. They found that whites were at greater risk than blacks, by a margin of 10.1% (17.1% vs. 7%). Moreover, the 23% IM detection rate in patients aged over age 70 years was significantly higher than the 15.5% rate in those under age 70. And to their surprise, there was no significant difference between the IM detection rate in men and women.
Nearly 15% of study participants with no measurable columnar-lined esophagus turned out to have IM. And two patients with low-grade dysplasia and one with adenocarcinoma were found among the group with no history of IM and no visible columnar-lined esophagus on upper endoscopy.
“This demonstrates that the absence of a measurable columnar-lined esophagus does not exclude patients from the risk of having intestinal metaplasia, dysplasia, or cancer at the gastroesophageal junction. Therefore evaluation of the gastroesophageal junction by biopsy or WATS should be considered during upper endoscopy, particularly in patients at increased risk for having intestinal metaplasia,” he concluded.
Dr. DeMeester reported serving as a consultant to BARD and receiving research funding from and serving as a paid speaker for CDx Diagnostics, which funded the trial.