Perioperative Avelumab and Chemotherapy for Gastroesophageal Adenocarcinoma: Long-Term Survival Outcomes

Long-term survival data for patients with locally advanced gastro-esophageal adenocarcinoma (GEA) treated with neoadjuvant chemoimmunotherapy are lacking. We describe the long-term disease-free survival (DFS) and overall survival (OS) outcomes of such patients treated with a novel neoadjuvant chemoimmunotherapy regimen, aDCF (avelumab with docetaxel/cisplatin/5-fluorouracil). The 50 patients included in the study were treated with 4 neoadjuvant cycles of aDCF followed by an en-bloc transthoracic resection after which 4 additional adjuvant cycles were planned to be given. An exploratory analysis of patients achieving major pathological response (MPR) was also performed. There were 50 patients included in the survival analysis. Clinical disease burden was high (cT3 44/50, 88%, N+ 31/50, 62%) with 49/50 (98%) completing neoadjuvant aDCF. All patients proceeded to surgery with MPR found in 9/50 (18%) patients. The median follow-up for the cohort was 71.5 months (range 43-105) with an estimated median DFS and OS of 61.0 months (95% CI not met) and 77.0 months (95% CI not met) corresponding to a 5-year DFS and OS of 50.0% and 60.0%. For patients with MPR, 5-year DFS and OS were 100%. There were no new safety signals. We conclude that aDCF is a feasible and novel regimen for patients with locally advanced esophagogastric adenocarcinoma providing durable survival outcomes. These outcomes seem enhanced among patients with MPR.