"Cytosponge - a sponge on a string that is swallowed and collects cells lining the esophagus for laboratory analysis - has been shown to diagnose Barrett's esophagus. Our study shows that adding laboratory markers enables the Cytosponge test to also be used to monitor the condition," Dr. Rebecca C. Fitzgerald of the University of Cambridge told Reuters Health by email. "Cytosponge was easy to implement, results were received within 6 to 11 days, and endoscopy was prioritized for 17% of patients found to be at high risk."
"Our large study on patients who underwent endoscopy and Cytosponge showed that high-risk patients, with a roughly 1-in-2 chance of having an abnormality, should have endoscopy. By contrast, low-risk patients, with a less than 2-in-100 chance of progressing to cancer, need much less frequent follow-up and may even avoid endoscopy," she added. "This is an important consideration during the pandemic, as concerns about COVID-19 infection risks have strained endoscopy services."
Dr. Fitzgerald and her colleagues developed and tested the Cytosponge biomarker panel for surveillance of patients with known Barrett's esophagus. In a paper in The Lancet Oncology, they describe how the test, coupled with a decision-tree algorithm, can help doctors monitor their patients over time.
The researchers conducted a retrospective, multicenter, cross-sectional study in consecutive adult patients being monitored by endoscopy for Barrett's esophagus (with intestinal metaplasia confirmed by TFF3 and a minimum Barrett's segment length of 1 cm). All participants had received the Cytosponge followed by endoscopy.
The researchers assigned the 557 participants recruited between 2011 and 2013 to the training cohort, and the 334 patients recruited from 2013 onwards to the validation cohort. They evaluated overexpression of p53, cellular atypia and 17 clinical demographic variables.
In 223 participants, they also tested a decision tree for Cytosponge triage.
From the new biomarker analysis, they identified three risk groups: high (atypia or p53 overexpression or both on Cytosponge); moderate (presence of clinical risk factors including age, sex, and segment length); and low (Cytosponge-negative and no clinical risk factors).
Cytosponge identified 39 (17%) of 223 patients as being at high risk (atypia or p53 overexpression, or both) and in need of endoscopy. Of these, the positive predictive value was 31% (12 of 39) for high-grade dysplasia or intramucosal cancer and 44% (17 of 39) for dysplasia of any grade.
Dr. Adarsh M. Thaker, an endoscopist at the University of California, Los Angeles, in North Hollywood, told Reuters Health by email, "A convenient test such as Cytosponge can help ensure that dysplasia or cancer are not missed, particularly when endoscopy may be less available, such as during a pandemic surge or for patients without easy access to an endoscopist."
"We are likely still underdetecting Barrett's, dysplasia and esophageal cancer in the community," added Dr. Thaker, who was not involved in the study. "As more performance data become available, we will hopefully see similarly encouraging results at the population level over a variety of regions."
Dr. Matthew Stachler, a molecular pathologist and assistant professor of pathology at the University of California, San Francisco, School of Medicine, who also was not involved in the study, told Reuters Health by email that further "studies confirming these results in other settings as well as determining the optimal set of biomarkers (Can other biomarkers besides cellular atypia and p53 immunostaining increase risk stratification?) will be important areas of study."
Cytosponge technology, including the device and TFF3 biomarker, is licensed by the Medical Research Council to Covidien (now Medtronic). Dr. Fitzgerald and a co-author are named on patents related to the test, and they have financial involvements with Cyted.
The Medical Research Council, Cancer Research UK, and Innovate UK funded the study.
SOURCES: https://bit.ly/3442iJH and https://bit.ly/3GlwBbG The Lancet Oncology, online January 11, 2022.
By Lorraine L. Janeczko
Posted on
site created by:
© 2024 Medicom Medical Publishers. All rights reserved. Terms and Conditions | Privacy Policy
HEAD OFFICE
Laarderhoogtweg 25
1101 EB Amsterdam
The Netherlands
T: +31 85 4012 560
E: publishers@medicom-publishers.com