The Long-Term Sequelae and Clinical Workload Resulting from Toxicities of Immune Checkpoint Inhibitor (ICI) Therapy in Patients with Cancer

BACKGROUND: Up to half of cancer patients treated with immune checkpoint inhibitors (ICIs) develop immune-related adverse events (irAEs). However, the long-term consequences of irAEs remain poorly characterized. OBJECTIVE: This study investigated the likelihood of chronic irAEs, challenges related to their corticosteroid treatment and clinical workload associated with their management. METHODS: We retrospectively analyzed 230 patients who received ICIs at Kuopio University Hospital, Finland, between the years 2015 and 2024. RESULTS: IrAEs were chronic in 60.9% of patients who developed toxicities. Thyroiditis was the most common chronic AE (40%). Of the patients with irAE+, 42.9% were treated with systemic corticosteroids and steroid-related AEs were observed in 58% of them. Corticosteroid usage for ≥ 3 months was associated with an increased risk of steroid-related AEs (< 3 months 38.2% vs ≥ 3 months 78.8%, p < 0.001). An average of 5.3 contacts with a medical oncologist was needed for the management of an irAE, with the highest workload associated with hepatitis (10.0 contacts/irAE) and colitis (6.1 contacts/irAE). CONCLUSIONS: The characterization of the long-term sequelae of irAEs and the associated clinical workload is crucial for proper patient education and clinical resource planning.