The Effect of Endoscopic Surveillance in Patients With Barrett's Esophagus: A Systematic Review and Meta-analysis.

BACKGROUND & AIMS: Guidelines recommend endoscopic surveillance of patients with Barrett's esophagus (BE) to identify those with dysplasia (a precursor of carcinoma) or early-stage esophageal adenocarcinoma (EAC) who can be treated endoscopically. However, it is unclear whether surveillance increases survival times of patients with BE. We performed a systematic review and meta-analysis to qualitatively and quantitatively examine evidence for the association of endoscopic surveillance in patients with BE with survival and other outcomes. METHODS: We searched publication databases for studies reporting the effects of endoscopic surveillance on mortality and other EAC-related outcomes. We reviewed randomized controlled trials, case-control studies, studies comparing patients with BE who received regular surveillance with those who did not receive regular surveillance, and studies comparing outcomes of patients with surveillance-detected EAC vs symptom-detected EACs. We performed a meta-analysis of surveillance studies to generate summary estimates using a random effects model. The primary aim was to examine the association of BE surveillance on EAC-related mortality. Secondary aims were to examine the association of BE surveillance with all-cause mortality and EAC stage at time of diagnosis. RESULTS: A single case-control study did not show any association between surveillance and EAC-related mortality. A meta-analysis of 4 cohort studies found that lower EAC-related and all-cause mortality were associated with regular surveillance (relative risk, 0.60; 95% CI, 0.50-0.71; hazard ratio, 0.75; 95% CI, 0.59-0.94). Meta-analysis of 12 cohort studies showed lower EAC-related and all-cause mortality among patients with surveillance-detected EAC vs symptom-detected EAC (relative risk, 0.73; 95% CI, 0.57-0.94; hazard ratio, 0.59; 95% CI, 0.45-0.76). Lead- and length-time bias adjustment substantially attenuated/eliminated the observed benefits. Surveillance was associated with detection of EAC at earlier stages. A randomized trial is underway to evaluate the effects of endoscopic surveillance on mortality in patients with BE. CONCLUSIONS: In a systematic review and meta-analysis of the effects of surveillance in patients with BE, surveillance as currently performed was associated with detection of earlier-stage EAC and may provide a small survival benefit. However, the effects of confounding biases on these estimates are not fully defined and may completely or partially explain the observed differences between surveyed and unsurveyed patients.