Global 
Deutschland Esophagus to Small Intestine
Gastroenterology. 2025;169(6):1233-1243.e8
Barrett’s oesophagus surveillance versus endoscopy at need study (BOSS): A randomized controlled trial
Background and aims: Barrett’s esophagus (BE) is a precursor lesion for esophageal adenocarcinoma (EAC). Surveillance endoscopy aims to detect early malignant progression; although widely practiced, it has not previously been tested in a randomized trial.
Methods: BOSS (Barrett’s Oesophagus Surveillance Versus Endoscopy at Need Study) was a randomized controlled trial at 109 centers in the United Kingdom. Patients with BE were randomized to 2-yearly surveillance endoscopy or “at-need” endoscopy, offered for symptoms only. Follow-up was a minimum of 10 years. The primary outcome was overall survival in the intention-to-treat population. Secondary outcomes included cancer-specific survival, time to diagnosis of EAC, stage of EAC at diagnosis, frequency of endoscopy, and serious adverse events related to interventions.
Results: There were 3,453 patients recruited; 1,733 patients were randomized to surveillance and 1,719 to at-need endoscopy. Median follow-up time was 12.8 years for the primary outcome. There was no evidence of a difference in overall survival between the surveillance arm (333 deaths among 1,733 patients) and the at-need arm (356 deaths among 1,719 patients; hazard ratio [HR] = 0.95; 95% CI: 0.82–1.10; stratified log-rank p = 0.503). There was no evidence of a difference for surveillance versus at-need endoscopy in cancer-specific survival (108 vs. 106 deaths from any cancer; HR = 1.01; 95% CI: 0.77–1.33; p = 0.926), time to diagnosis of EAC (40 vs. 31 patients had a diagnosis of EAC; HR = 1.32; 95% CI: 0.82–2.11; p = 0.254), or cancer stage at diagnosis. Eight surveillance patients (0.46%) and 7 at-need patients (0.41%) reported serious adverse events.
Conclusions: Surveillance did not improve overall survival or cancer-specific survival. At-need endoscopy may be a safe alternative for low-risk patients.