Cardiovascular events after cancer immunotherapy as oncologic emergencies: Analyses of 610 head and neck cancer patients treated with immune checkpoint inhibitors.

BACKGROUND: Cardio-oncology and emergency medicine are closely collaborative, as many cardiac events in cancer patients require evaluation and treatment in the emergency department (ED). Immune checkpoint inhibitors (ICIs) have become a common treatment for patients with head and neck cancer (HNC). However, the immune-related adverse events (irAEs) from ICIs can be clinically significant.

METHODS: We reviewed and analyzed cardiovascular diagnoses among HNC patients who received ICI during the period April 1, 2016-December 31, 2020 in a large tertiary cancer center. Demographics, clinical and cancer-related data were abstracted, and billing databases were queried for cardiovascular disease (CVD)-related diagnosis using International Classification of Disease-version10 (ICD-10) codes. We recorded receipt of care at the ED as one of the outcome variables.

RESULTS: A total of 610 HNC patients with a median follow-up time of 12.3 months (median, interquartile range = 5-30 months) comprised our study cohort. Overall, 25.7% of patients had pre-existing CVD prior to ICI treatment. Of the remaining 453 patients without pre-existing CVD, 31.5% (n = 143) had at least one CVD-related diagnosis after ICI initiation. Tachyarrhythmias (91 new events) was the most frequent CVD-related diagnosis after ICI. The time to diagnosis of myocarditis from initiation of ICI occurred the earliest (median 2.5 months, 1.5-6.8 months), followed by myocardial infarction (3.7, 0.5-9), cardiomyopathy (4.5, 1.6-7.3), and tachyarrhythmias (4.9, 1.2-11.4). Patients with myocarditis and tachyarrhythmias mainly presented to the ED for care.

CONCLUSION: The use of ICI in HNC is still expanding and the spectrum of delayed manifestation of ICI-induced cardiovascular toxicities is yet to be fully defined in HNC survivors.