765. PATTERNS, TIMING, AND SURVIVAL OF RECURRENCE FOLLOWING SURGERY FOR ESOPHAGEAL ADENOCARCINOMA IN THE EUROPEAN MULTICENTRE ENSURE STUDY

Abstract Background After surgery for esophageal cancer approximately half of patients will develop disease recurrence. A more accurate and detailed understanding of the pattern, timing, treatment and prognosis of initial recurrence sites can guide improvements in surveillance and therapy. Therefore, the aim of this study was to accurately describe the pattern and timing of esophageal cancer recurrence, and to assess the distinct survival patterns of these recurrence locations. Methods This study included all patients who underwent surgical resection for esophageal and junctional adenocarcinoma registered in the ENSURE study. ENSURE was an international multicenter study of consecutive patients undergoing surgery for esophageal and esophagogastric junction cancers between 2009 and 2015 across 20 centers in Europe and Canada (NCT03461341). The first recurrence site was recorded and recurrence-free survival (RFS) was estimated using Kaplan-Meier curves. Sites of first recurrence were stratified into different groups and survival outcomes post recurrence detection were estimated using Kaplan-Meier curves. Results Of 3397 eligible patients, 1310 patients had disease recurrence with comprehensive follow-up data available (median RFS of 12.1 months). First recurrence was detected at multiple distant sites (n=469; 37.3%) or at a single distant site (n=463; 33.7%), while isolated local recurrence occurred in 189 (14.4%) patients. Liver-only recurrence occurred significantly earlier (median 9.0 months), while lung-only (15.2 months) and local-only occurred later (17.8 months). Patients with multiple-sites and liver-only recurrence had significant worse median post recurrence survival (7.4 and 8.3 months, respectively) when compared with lung- or local-only recurrence (10.4 and 15.9 months, respectively). Conclusion This study demonstrates that specific recurrence locations of esophageal cancer possess distinct RFS curves. Furthermore, specific recurrence locations result in different post recurrence survival outcomes. This information can help guide improvements in surveillance after esophageal cancer surgery and decisions regarding treatment of esophageal cancer recurrence.