Barrett’s esophagus (BE) is the only known precursor of esophageal adenocarcinoma (EAC). The rationale for early detection of BE rests on the premise that, after the diagnosis of BE, patients can be placed under endoscopic surveillance to detect prevalent and incident dysplasia and EAC. Randomized controlled trials have demonstrated that endoscopic eradication therapy (EET) of low-grade dysplasia (LGD) and high-grade dysplasia (HGD) can reduce progression to EAC. Guidelines support endoscopic screening for BE in those with multiple (three or more) risk factors.
However, endoscopy is expensive, invasive, and not widely utilized (less than 10% of those eligible are screened). Most patients with BE are unaware of their diagnosis and hence not under surveillance. Nonendoscopic techniques of BE detection – swallowed cell collection devices providing rich esophageal cytology specimens combined with biomarkers – are being developed. Case-control studies have shown promising accuracy and a recent UK pragmatic primary care study showed the ability of this technology to increase BE detection safely.
Detection of dysplasia in endoscopic surveillance is critical and the neoplasia detection rate (NDR) has been recently proposed as a quality marker. The NDR is the ratio of HGD+EAC detected to all patients with BE undergoing their first surveillance endoscopy. A recent systematic review and meta-analysis showed an inverse association between NDR and postendoscopy BE neoplasia. Additional and prospective studies are required to further correlate NDR values to clinically relevant outcomes similar to the association between adenoma detection rate and postcolonoscopy colorectal cancer.
Detection of dysplasia with endoscopic surveillance is challenging because of sampling error inherent in the Seattle protocol. A recent technology, Wide Area Transepithelial Sampling–3D (WATS), combines the concept of increased sampling of the BE mucosa by using a stiff endoscopic brush followed by use of artificial intelligence neural network enabled selection of abnormal cells, which are presented to a pathologist. This technology has been shown to increase dysplasia and HGD detection, compared to endoscopic surveillance, in a systematic review and meta-analysis. However, WATS is negative in a substantial proportion of cases in which endoscopic Seattle protocol reveals dysplasia. In addition, only limited data are available on the natural history of WATS LGD or HGD. Confirmation of WATS-only dysplasia (LGD, HGD, or EAC) by endoscopic histology is also recommended before the institution of EET. Finally, assessment of progression risk in those with BE is critical to enable more personalized follow up recommendations. Clinical risk scores integrating age, sex, smoking history, and LGD have been proposed and validated. A recent tissue systems pathology test has been shown in multiple case-control studies to identify a subset of BE patients who are at higher risk of progression, independent of LGD. This test is highly specific but only modestly sensitive in identifying progressors.
Dr. Iyer is professor of medicine, director of the Esophageal Interest Group, and codirector of the Advanced Esophageal Fellowship at the Mayo Clinic College of Medicine and Science, Rochester, Minn. He reports relationships with Exact Sciences, Pentax Medical, and others. These remarks were made during one of the AGA Postgraduate Course sessions held at DDW 2022.