Adjuvant Immunotherapy in Curative Intent Esophageal Cancer Resection Patients: Real-World Experience within an Integrated Health System

SIMPLE SUMMARY: This is an invited study for the special edition, “Role of Immunotherapy in Gastroesophageal Cancers: Advances, Challenges and Future Strategies”. Esophageal cancer is a disease with one of the lowest survival rates. For patients who have resectable tumors, current guidelines recommend treatment with neoadjuvant chemoradiation followed by surgery if feasible. Recent clinical trials have suggested that treating patients with residual pathologic disease with adjuvant immunotherapy can increase overall survival. The aim of our retrospective study was to assess the real-world outcomes of patients at a regionalized esophageal cancer center in a large integrated health system. We found that the majority of patients are unable to complete immunotherapy treatment (82%), most commonly due to disease progression or side effects. In logistic regression, immunotherapy also did not significantly impact 1-year overall survival. Our experience within the first two years of adjuvant immunotherapy being introduced suggests that real-world outcomes vary greatly outside of those seen in a clinical trial. ABSTRACT: Background: Adjuvant immunotherapy has been shown in clinical trials to prolong the survival of patients with esophageal cancer. We report our initial experience with immunotherapy within an integrated health system. Methods: A retrospective cohort study was performed reviewing patients undergoing minimally invasive esophagectomy at our institution between 2017 and 2021. The immunotherapy cohort was assessed for completion of treatment, adverse effects, and disease progression, with emphasis on patients who received surgery in 2021 and their eligibility to receive nivolumab. Results: There were 39 patients who received immunotherapy and 137 patients who did not. In logistic regression, immunotherapy was not found to have a statistically significant impact on 1-year overall survival after adjusting for age and receipt of adjuvant chemoradiation. Only seven patients out of 39 who received immunotherapy successfully completed treatment (18%), with the majority failing therapy due to disease progression or side effects. Of the 17 patients eligible for nivolumab, 13 patients received it (76.4%), and three patients completed a full course of treatment. Conclusions: Despite promising findings of adjuvant immunotherapy improving the survival of patients with esophageal cancer, real-life practice varies greatly from clinical trials. We found that the majority of patients were unable to complete immunotherapy regimens with no improvement in overall 1-year survival.