In a study reported in The Lancet Oncology, Pilonis et al found that nonendoscopic cell collection device (marked as the Cytosponge)–detected atypia and p53 overexpression could be used in combination with clinical risk factors to triage patients with Barrett’s esophagus for endoscopic surveillance.
As stated by the investigators, “Endoscopic surveillance is recommended for patients with Barrett’s esophagus because, although the progression risk is low, endoscopic intervention is highly effective for high-grade dysplasia and cancer. However, repeated endoscopy has associated harms and access has been limited during the COVID-19 pandemic.”
The Cytosponge is a nonendoscopic esophageal cell collection device.
Study Details
The study included patients from clinical studies undergoing endoscopic surveillance, divided into a training cohort (n = 557) and a validation cohort (n = 334). All patients had undergone Cytosponge testing and confirmatory endoscopy between July 2011 and April 2019. Endoscopic biopsy diagnosis of high-grade dysplasia or cancer was the primary endpoint. The feasibility of Cytosponge triage was assessed in a real-world prospective cohort of 223 patients beginning in August 2020.
Key Findings
High-grade dysplasia or cancer was detected by endoscopic biopsy in 92 patients (17%) in the training cohort and 35 patients (10%) in the validation cohort.
In analyses using Cytosponge biomarkers and clinical risk factors, three risk groups were identified:
- High risk = atypia, p53 overexpression, or both on Cytosponge
- Moderate risk = clinical risk factors consisting of Barrett’s esophagus segment length > 5 cm or circumferential length ≥ 3 cm and either male sex or age > 60 years
- Low risk = Cytosponge-negative and no clinical risk factors.
The risk of high-grade dysplasia or intramucosal cancer in the high-risk group was 52% (68 of 132 patients) in the training cohort and 41% (31 of 75) in the validation cohort, compared with 2% (5 of 210) and 1% (2 of 185) in the low-risk group, respectively.
Compared with the low-risk group, sensitivity in the combined moderate- and high-risk groups in the combined training and validation cohorts was 94% for high-grade dysplasia or intramucosal cancer and 88% for any grade of dysplasia. Overall, the combination of Cytosponge-positive results and presence of the clinical risk factors had sensitivity and specificity in identifying high-grade dysplasia or cancer of 77% and 86% in the training cohort and 80% and 87% in the validation cohort. Sensitivity and specificity for any grade of dysplasia were 70% and 86% and 69% and 91% in the two cohorts.
In the real-world cohort, Cytosponge results prospectively identified 39 (17%) of 223 patients as high risk (atypia, p53 overexpression, or both) requiring endoscopy; among these patients, the positive predictive value was 31% (12 of 39 patients) for high-grade dysplasia or intramucosal cancer and 44% (17 of 39) for any grade of dysplasia.
The investigators concluded, “Cytosponge atypia, p53 overexpression, and clinical risk factors (age, sex, and segment length) could be used to prioritize patients for endoscopy. Further investigation could validate their use in clinical practice and lead to a substantial reduction in endoscopy procedures compared with current surveillance pathways.”
Rebecca C. Fitzgerald, MD, of the MRC Cancer Unit, Hutchison-MRC Research Centre, University of Cambridge, is the corresponding author for The Lancet Oncology article.
Disclosure: The study was funded by the UK Medical Research Council, Cancer Research UK, and others. For full disclosures of the study authors, visit thelancet.com.
