Nivolumab-associated myositis myocarditis and myasthenia and anti-striated muscle antibodies.

An 82-year-old man was treated with neo-adjuvant nivolumab (programmed cell death protein 1 or PD-1 inhibitor) for local recurrence of melanoma developed myositis, myocarditis and a myasthenic-like syndrome with a fatal outcome. The occurrence of these three conditions may constitute a new immune checkpoint-induced syndrome. The relevance of the clinical features and the immunology is discussed. This case highlights the special role of anti-striated muscle antibodies as a predictor of mortality.