Inpatient admissions related to immune-related adverse effects (irAE) among patients treated with immune checkpoint inhibitors for advanced malignancy: A tsunami is coming, but are we ready?

Abstract

127 Background: Disruption of the immune system with immune checkpoint inhibitors can result in a multitude of immune-related adverse effects (irAE). While irAEs have been well-reported in clinical trials, the impact and magnitude of irAE’s in the real-world, particularly inpatient is unclear. Methods: Data was collected on patients with advanced malignancy who experienced a suspected irAE needing admission to an academic hospital (Feb 2011 to June 2017). Each case was reviewed comprehensively by minimum of two reviewers, including one sub-specialist. In addition, oncologists at our institution were surveyed regarding their confidence about managing patients with irAEs. Results: Over a span of 6 years, there were 343 hospitalizations for suspected irAEs and the majority (65%; N = 223) were confirmed irAEs that required treatment with immunosuppression or therapy stopped as result. The mean length of stay was 6.3 days (range 1 to 31 days), readmission rate for another irAE event 25%, total readmission rate 61.7%, and inpatient mortality 8%. The most common irAEs were enterocolitis (43.9%), pulmonary (16%), hepatic (15%), neurological (8.9%), endocrinopathies (7.1%), rheumatological (4%), dermatological (3%), cardiovascular (3%), renal (1.8%), and allergy (1.3%). Over the past 5 years, there was a significant increase in admissions due to irAEs (admissions in 2016 vs 2011, odds ratio = 3.07; p < 0.01). The Cancer Center survey (N = 26) revealed majority of oncologists do not feel very comfortable managing irAEs, and 48% felt that irAE complications should be managed on a different service. Conclusions: irAEs from immune checkpoint inhibitors can result in prolonged hospitalizations, high rate of readmissions, and mortality. The number of patients admitted due to irAEs has significantly increased by more than three-fold in the recent years, but majority of oncologists do not feel very comfortable managing irAEs. Consequently, there is a critical need for coordinated multidisciplinary approach, comprehensive provider education, and translational research program for early detection and intervention.