S0423 “WATS” the Incremental Yield of Wide-Area Transepithelial Sampling for Dysplasia Detection in Barrett’s Esophagus? A Systematic Review and Meta-Analysis

Abstract

INTRODUCTION: Seattle protocol forceps biopsies (FB) are currently recommended for surveillance in Barrett’s esophagus (BE). Dysplasia detection is limited by sampling error. Wide-area transepithelial sampling (WATS) utilizes computer-aided diagnosis of esophageal brushings to increase dysplasia detection. We assessed the incremental yield of WATS compared to FB and limitations of published data in a systematic review and meta-analysis. METHODS: We queried multiple scientific databases for studies utilizing WATS with FB from 2000–2020. We utilized the arcsine transformation with a fixed-effects meta-analysis of single arm proportions for analysis given the small number of studies. Primary outcome was the incremental yield of WATS over FB for dysplastic BE (IND/LGD + HGD + EAC) as a composite. Secondary outcomes were incremental yield of WATS for HGD/EAC, and the rate of reconfirmation of incremental WATS dysplasia on subsequent FB. RESULTS: We included 6 full-length manuscripts (from 2011 to 2020), studying 37,468 patients (6 included data for dysplastic BE, and 4 for HGD/EAC), Study characteristics are shown in the Table. All WATS samples were read by pathologists at CDx Diagnostics (Suffern, NY). BE histology was confirmed by 2 expert GI pathologists in only 2 (33%) studies. Meta-analysis of 6 studies demonstrated that FB diagnosed dysplasia in 5.8% (95% CI: 5.1%–6.6%) of cases, while WATS added an incremental yield of 4.5% (95% CI: 3.9%–5.2%; Figure 1). Meta-analysis of 4 studies demonstrated that FB diagnosed HGD/EAC in 0.6% (95% CI 0.4%–0.9%) of patients, while WATS added an incremental yield of 0.4% (95% CI: 0.2%–0.6%; Figure 2). Notably, WATS was negative in 1%–45% of cases where FB identified dysplasia. Only 1 study reported reconfirmation of WATS dysplasia on subsequent endoscopy: only 7 of 23 (30%) WATS dysplasia (+) patients had dysplasia on subsequent FB. In 3 studies the incremental yield of WATS dysplasia was reported in several cases with FB histology negative for intestinal metaplasia (85% of cases). No endoscopic data was available in these cases. CONCLUSION: WATS appears to increase the yield of dysplastic BE and HGD/EAC as an adjunct to FB. However, in most studies, this incremental yield is not reconfirmed by FB, WATS reads are done only by CDx pathologists and FB dysplasia is not confirmed by expert GI pathologists. Long-term follow up is required to ascertain dysplasia outcomes in patients with dysplasia based solely on WATS.Figure 1Figure 2Table 1