Immune-related adverse events: a retrospective look into the future of oncology in the intensive care unit.

Background: Immune checkpoint inhibitors have reshaped the standard of care in oncology. However, they have been associated with potentially life-threatening immune-related adverse events. With the growing indications of immune checkpoint inhibitors and their position as a pillar of cancer treatment, intensive care physicians will be increasingly confronted with their side effects. The outcome of patients with severe immune-related adverse events in the intensive care unit remains unknown. This retrospective multicentric study aims to describe the characteristics of patients admitted to the intensive care units of 4 academic hospitals in Paris area while receiving immune checkpoint inhibitor treatment between January 2013 and October 2019.

Results: Over the study period, 112 cancer patients who received immune checkpoint inhibitors were admitted to the intensive care unit within 60 days after the last dose. ICU admission was related to immune-related adverse events (n = 29, 26%), other intercurrent events (n = 39, 35%), or complications related to tumor progression (n = 44, 39%). Immune-related adverse events were pneumonitis (n = 8), colitis (n = 4), myocarditis (n = 3), metabolic disorders related to diabetes (n = 3), hypophysitis (n = 2), nephritis (n = 2), meningitis or encephalitis (n = 2), hepatitis (n = 2), anaphylaxis (n = 2) and pericarditis (n = 1). Primary tumors were mostly melanomas (n = 14, 48%), non-small-cell lung cancers (n = 7, 24%), and urothelial carcinomas (n = 5, 17%). Diagnosis of melanoma and a neutrophil/lymphocyte ratio < 10 were associated with immune-related diagnosis versus other reasons for ICU admission. During their ICU stay, immune-related adverse events patients needed vasopressors (n = 7), mechanical ventilation (n = 6), and extra-corporeal membrane oxygenation (n = 2). One-year survival was significantly higher for patients admitted for irAE compared to patients admitted for other reasons (p = 0.004).

Conclusions: Admission to the intensive care unit related to immune-related adverse event was associated with better outcome in cancer patients treated with immune checkpoint inhibitors. Our results support the admission for an intensive care unit trial for patients with suspected immune-related adverse events.