Immune Checkpoint Inhibitor Induced Pericarditis and Encephalitis in a Patient Treated With Ipilimumab and Nivolumab for Metastatic Melanoma: A Case Report and Review of the Literature

Immune checkpoint inhibitors (ICIs) are now a mainstay of cancer treatment. Although rare, fulminant and fatal toxic effects may complicate these otherwise transformative therapies; characterizing these events requires integration of global data.

Background. Immune-checkpoint-inhibitors (ICIs) have dramatically improved clinical outcomes in multiple cancer types and are increasingly being used in early disease settings and in combinations. However, ICIs can also cause severe or even fatal immune-mediated adverse-events (irAE). Here, we identify and characterize significant cardiovascular irAE (CV-irAEs) associated with ICIs. Methods. We used VigiBase, the WHO’s global Individual-Case-Safety-Report database to identify drug-AE related to ICIs (n:31,321) and related to other drugs (n:16,343,451) through 01/2018. We evaluated the association between ICI and CV events using Reporting-Odds-Ratio (ROR) and Information-Component (IC). IC is an indicator value for disproportionate Bayesian reporting that compares observed and expected values to find drug-AE associations. IC 025 is the lower-end of IC 95% credibility-interval and an IC 025 >0 is considered statistically significant. Findings. Using this agnostic approach, we identified multiple CV entities over-reported after ICI treatment compared to the entire database. ICI treatment was associated with higher reporting of myocarditis (n:122, ROR: 11.21 [9.36–13.43], IC 025 :3.2), pericardial diseases (n:95, ROR: 3.8 [3.08–4.62], IC 025 :1.63), and vasculitis (n:82, ROR: 1.56 [1.25–1.94], IC 025 :0.03), including temporal-arteritis (n:18, ROR: 12.99 [8.12–20.77], IC 025 :2.59). These CV-irAE affected mostly men (58–67%), with a wide age range (20–90 years) and occurred early after ICI administration (40–80% within one month of first ICI administration). Pericardial disorders were reported more often in patients with lung cancer (56.3%) whereas myocarditis and vasculitis were more commonly reported in patients with melanoma (40.7% and 60%, respectively; p<0.001). Vision was impaired in 27.8% of temporal-arteritis cases. CV-irAE were serious in the majority of cases (>80%), with fatalities occurring in 50% of myocarditis cases, 21.1% of pericardial disorders and 6.1% of vasculitis (p<0.0001). Among myocarditis cases, fatality was most frequent in ICI combination therapy compared to ICI monotherapy (65.6% vs. 44.4%, p:0.04). Interpretation. ICI may lead to severe and disabling inflammatory CV-irAEs early during therapy. Besides life-threatening myocarditis, these toxicities include pericardial disorders, as well as temporal arteritis with a risk for blindness.