Nivolumab-induced Myocarditis Successfully Treated with Corticosteroid Therapy: A Case Report and Review of the Literature

Matsuo, Keisuke; Ishiguro, Takashi; Najama, Takatomo; Shimizu, Yoshihiko; Kobayashi, Yasuhito; Mutou, Makoto

Considering the mechanism underlying the side effects of ICIs as described above, steroids are often administered to counteract serious ir-AEs (16) . In our patient, in addition to heart failure, complete atrioventricular block developed, and it was necessary to administer a steroid. Among the 13 cases reported so far, none of the patients underwent observation without treatment. The recently published clinical practice guidelines state that all ICI patients complicated with myocarditis should be treated with corticosteroids regardless, of the grade of cardiac toxicities (19) . The therapeutic options in the 13 reported cases include prednisolone in 5, methylprednisolone in 4, mycophenolate mofetil in 1, methylprednisolone and infliximab in 1, methylprednisolone and intravenous anti-thymus immunoglobulin in 1, and no mention of therapy in 1 case. Corticosteroid therapy seems effective in most cases, but deaths in patients treated with steroid therapy have also been reported (3). One patient with recurrence of myocarditis after nivolumab readministration eventually died; we therefore consider that nivolumab should not be readministered in such cases (5) .