NONENDOSCOPIC DETECTION OF BARRETT'S ESOPHAGUS IN PATIENTS WITHOUT GERD SYMPTOMS

Background: Screening efforts for Barrett’s Esophagus (BE) predominantly focus on performing upper endoscopy (EGD) on patients with GERD symptoms who have additional risk factors for BE. However, cost and invasiveness preclude EGD in those who have no prior GERD symptoms, despite having other risk factors, representing missed opportunities for BE screening in approximately 40% of patients who eventually develop esophageal adenocarcinoma (EAC).

Aim: The aim of this study is to evaluate if non-endoscopic methods can enable BE detection in an at-risk population without GERD symptoms.

Methods: Patients presenting for colonoscopy who have not undergone previous EGD plus have ≥3 BE risk factors (age >50 years, male sex, white race, smoking history, family history of BE/EAC, or central obesity i.e., waist measurement >100 cm) without history of chronic GERD were prospectively recruited for non-endoscopic screening. Trained nurses administered the EsoCheck (EC, Lucid Diagnostics) encapsulated balloon to obtain a sample from the GEJ and distal esophagus. The EC samples were assayed with the EsoGuard (EG, Lucid Diagnostics) BE detection methylated DNA marker panel. Patients with a positive EG result were offered standard-of-care EGD, while patients with a negative EG result were offered free research EGD. Positive predictive value (PPV), negative predictive value (NPV), and BE prevalence were calculated to assess effectiveness of non-endoscopic methods for detecting disease in an at-risk population without GERD symptoms.

Results: 56% of eligible patients who were approached agreed to participate, 94% of whom successfully swallowed EC and provided a distal esophageal sample. The mean age of the 89 subjects was 61.1 years, 87 (98%) were white, 87 (98%) were male, 49 (55%) had a prior smoking history, and 24 (27%) were centrally obese. Twenty-three (26%) had a positive EG result of which 19 underwent a follow-up EGD (82.6%). Nondysplastic BE was detected in 6 (31.6%) EG positive patients: 5 short segment (< 3 cm) and 1 long segment (>3 cm) BE. Of the 57 (64%) patients with a negative EG result, 18 underwent a follow-up EGD (32%), none (0%) of whom had BE. Since several patients who produced a positive/negative EG result declined follow-up EGD, a logistic regression model was fitted to predict their phenotypes using age, smoking history, waist measurement, risk score, and EG result as covariates. The estimated PPV with 95% C.I. was 0.37 [0.27, 0.47] and estimated NPV with 95% C.I. was 0.99 [0.95, 1.00]. BE prevalence was estimated to be 8%.

Conclusion: Patients without chronic GERD who have ≥3 BE risk factors have a moderately high prevalence of BE. Non-endoscopic detection with EC/EG can effectively identify BE, enabling expansion of screening to this larger at-risk population. Those with a negative EG assay are unlikely to have BE and do not require an EGD.