292 Immune checkpoint inhibitor induced overlapping cardiac and neuromuscular toxicities: Highlight of early diagnosis, early initiation of immunosuppressive therapy and multidisciplinary management. (10th December 2020)

• Record Type: Journal Article
• Authors: Wai Siu, Ho; O'Neill, Robert; Tong, Matthew; Hong, JunHee; Harris, Carole A; Aghmesheh, Morteza; Soudy, Hussein
• Is Part Of: Journal for immunotherapy of cancer. Volume 8(2020)Supplement 3
• Page Start: A178
• Page End: A179
• Publication Date: 2020-12-10
• Subjects: Cancer -- Immunotherapy -- Periodicals; Cancer -- Immunological aspects -- Periodicals; Tumors -- Immunological aspects -- Periodicals; Immunotherapy -- Periodicals; 616.99406105
• DOI: 10.1136/jitc-2020-SITC2020.0292
• Languages: English
• ISSNs: 2051-1426

Abstract

Abstract : Background: The use of immune checkpoint inhibitors (ICIs) against programmed cell death protein -1 (PD-1), its ligand (PD-L1) and cytotoxic T- lymphocyte associated protein 4 (CTLA4) have been increasing. Immune induced myocarditis, myositis and myasthenia gravis are rare but potentially severe complications from these agents. Here we report 3 cases of ICI induced myocarditis, myositis, myasthenia gravis and transaminitis as a cluster, and highlights early diagnosis, prompt initiation of steroid sparing immunosuppressive therapy and multidisciplinary management. Methods: Three patients received anti-PD-1 ICIs developed cardiac, neuromuscular complications and transaminitis within 4 weeks after initiation. Clinical data were retrospectively reviewed from medical records. Results: All patients had elevated cardiac enzymes, developed complete heart block and underwent coronary catheterisation and pacemaker insertion. All patients developed myositis and myasthenia gravis (table 1 ) and were managed by multi-disciplinary team involving oncology, cardiology and neurology. Single-fibre electromyography was performed to confirm presence of myositis. One of three patients had positive acetylcholinesterase antibody, anti- muscle specific kinase antibody was negative in all cases. All patients developed grade 2–3 transaminitis with normal bilirubin. All patients received high-dose steroids. Steroid sparing therapy including intravenous immunoglobulin and mycophenolate mofetil were used early in 2 cases and was associated with rapid recovery of toxicities. Conclusions: ICI induced myocarditis can be associated with myositis, myasthenia gravis and transaminitis. A high index of suspicion, comprehensive investigations and early involvement of multi-disciplinary teams are key to early accurate diagnosis. In steroid refractory cases, we propose early initiation of steroid sparing immunosuppressive therapy after 3 days. Consent: Written informed consent was obtained from the patient for publication of this abstract and any accompanying images. A copy of the written consent is available for review by the Editor of this journal.