WATS3D , formerly known as EndoCDx, is a computer-assisted biopsy adjunct to standard forceps biopsy of the esophagus which increases the tissue area sampled and therefore, increases the yield of patients identified with abnormality in the esophagus. Unlike standard cytology brushes that are typically soft and primarily designed to gently remove spontaneously exfoliated squamous cells in the esophagus, the WATS3D Biopsy is specifically designed to consistently sample deeper layers of the more firmly attached glandular epithelium found in Barrett’s esophagus.
In addition, the analysis of WATS3D specimens is aided by a high speed computer scan which identifies potentially abnormal cells, cell clusters and abnormal glandular cells on a high resolution video monitor for specially trained pathologists to review.
In clinical trials, WATS3D biopsy has been demonstrated to significantly increase the detection of Barrett's esophagus and esophageal dysplasia (1-2). By utilizing both methods, forceps biopsies and brush biopsies to evaluate esophageal disease in your patients, the number of patients identified with Barrett’s esophagus and esophageal dysplasia will be much greater than by the use of forceps biopsies alone.
"Seeking dysplasia in a segment of Barrett's esophagus is like looking for the proverbial needle in a haystack. Academic centers tend to perform numerous forceps biopsies on each of the high risk patients that they follow. The fact that the brush biopsy with computer-assisted tissue analysis was found to increase detection by over 40% in even these highly experienced esophageal GI specialty centers demonstrates the potential of this technique"
- Sharmila Anandasabapathy, MD, Chief of Endoscopy at The Mount Sinai Medical Center
WATS3D Technique is Simple
With the esophagus intubated and the esophageal mucosa clearly visualized, a WATS biopsy of the suspected area and/or squamocolumnar junction should be obtained.
The WATS tip is retracted into its surrounding sheath and the brush passed down the biopsy channel. The tip should be advanced and placed against the surface of the mucosa. While maintaining firm pressure, the tip should be rotated and repeatedly passed back and forth over the abnormality and/or squamocolumnar junction until pinpoint bleeding is observed.
Once the sample is collected, the WATS tip is again retracted into the surrounding sheath and the brush removed from channel. The cellular material is spread from the instrument onto the bar-coded side of the enclosed glass slide. The bristle portion of WATS is clipped off into the enclosed vial. The sample is then sent to the CDx for processing and analysis.
Full Transepithelial Sample
Images of abnormal cells detected by the WATS biopsy from patients who were cup forceps biopsy negative for both Barrett’s and Dysplasia.
A specimen smear and cellblock are prepared from the sample and analyzed with the aid of a proprietary high speed computer which localizes potentially abnormal cells and cell clusters through a combined morphological, molecular and DNA ploidy analysis. Potentially abnormal cells and cell clusters are selected by the computer for examination on a high resolution video monitor by a specially trained pathologist who makes the final diagnosis.
Benefits of the WATS3D Biopsy
In published clinical trials, EndoCDx® (now WATS3D®) has been demonstrated to significantly increase the detection of Barrett's esophagus and esophageal dysplasia when used as an adjunct to standard forceps biopsy.
In Patients Being Screened for Barrett’s Esophagus (BE) and esophageal dysplasia (ED), EndoCDx® Increased the Detection of BE by 40% and ED by 88% (1)
In a High-Risk Barrett’s Esophagus Surveillance Population, EndoCDx® Increased the Detection of ED by 42% (2).
- The EndoCDx brush increases the tissue area sampled.
- The EndoCDx brush is specifically designed to consistently sample deeper layers of the more firmly attached glandular epithelium found in Barrett’s esophagus.
- Decreases sampling errors inherent in random, forceps biopsies.
- Analysis of EndoCDx specimens is aided by a high speed computer scan which identifies potentially abnormal cells, cell clusters and abnormal glandular cells.
- Increasing detection of esophageal dysplasia and carcinoma can potentially in improve the poor survival rate associated with esophageal adenocarcinoma.
In recent years, there has been a dramatic increase in the incidence of Barrett's esophagus and esophageal adenocarcinoma. In fact, the frequency of esophageal adenocarcinoma has quadrupled over the past few decades, and its incidence has increased faster than any other cancer in the United States. The sequence of events from Barrett's esophagus to adenocarcinoma encompasses several stages including low-grade and high-grade dysplasia. Despite the advances in surgery and chemotherapy, the dismal 5-year survival rate for esophageal cancer remains unchanged, and efforts toward early detection of dysplasia have not been successful.
A number of obstacles complicate the early detection and diagnosis of Barrett's esophagus, dysplasia and carcinoma of the esophagus. Much of the delay has been attributed to the inadequate current method aimed at decreasing the death rate from esophageal cancer, specifically, endoscopically screening patents with chronic gastroesophageal reflux disease for Barrett's esophagus.
During endoscopy, random, small samples of esophageal tissue are collected for biopsy, often missing the abnormal tissue requiring evaluation and treatment. Even systematic four-quadrant biopsies performed at 1- 2cm intervals result in the majority of esophageal tissue still untested. Since esophageal dysplasia and early cancer are often highly focal, random forceps biopsy procedures often miss abnormalities that are located between the sampled areas.
Another inherent problem in the early detection of adenocarcinoma is in the histologic diagnosis of Barrett's esophagus and dysplasia. The recognition and grading of these conditions is subject to significant interobserver variability, particularly with active inflammation in patients with ongoing reflux disease.
WATS3D overcomes the obstacles of sampling the esophagus for disease. Its use as an adjunct to standard mucosal forceps biopsies for the early detection of esophageal dysplasia and carcinoma can potentially result in improving the poor survival rate associated with esophageal adenocarcinoma.