Effect of multimodal therapy in the treatment of adenocarcinoma of the esophagus and gastroesophageal junction : a population-based analysis from the German Clinical Cancer Registry Group

PURPOSE: Multimodal treatment regimes combining surgery with perioperative chemotherapy and/or preoperative radiochemotherapy have become common treatment-modalities in resectable esophageal adenocarcinoma with controversial effects on oncological outcome. METHODS: This population-based analysis was derived from 24 German cancer registries from 2000 to 2018. The overall survival was compared over three time periods, 2000-2006: pre-neoadjuvant era (PRE-NEO); 2007-2012: implementation of neoadjuvant treatment (NEO); 2013-2018: neoadjuvant/multimodal treatment strategies (POST-NEO). RESULTS: For patients with adenocarcinoma of the esophagus (EAC) and gastroesophageal junction (GEJ), cTNM staging was documented in 9738 patients: Stage I (n=1405 (14%)), Stage II (n=1360 (14%)); Stage III (n=2680 (28%)); Stage IV (n=4293 (44%). The overall survival improved steadily over time for GEJ and EAC. Patients with Stage IV disease decreased over time in both tumor locations (GEJ: 71% PRENEO; 40% POST-NEO; EAC: 48% PRE-NEO to 34 %POST-NEO. Curative intended therapy increased over time (GEJ: 23% PRE-NEO; 50% POST-NEO; EAC: 29% PRENEO to 52% POST-NEO). In cTNM Stage II, perioperative chemotherapy and neoadjuvant radio chemotherapy followed by surgery were associated with longer overall survival in GEJ but not EAC compared to surgery alone. In Stage III, both multimodal treatment approaches were associated with longer overall survival in both EAC and GEJ patients when compared to surgery alone. Despite an obvious trend toward perioperative therapy, there was no statistical superiority between perioperative chemotherapy or neoadjuvant radiochemotherapy. CONCLUSION: Multimodal therapy was independently associated with improved overall survival, particularly in patients with cTNM Stage III disease and Stage II GEJ tumors. These findings support current guideline-based treatment strategies and underscore the relevance of multimodal care in appropriately selected patients.