To investigate the diagnostic accuracy of neuromuscular autoantibodies in patients with ICI-induced myositis, myocarditis, or MG, we selected the six most abundant autoantibodies (anti-heart muscle, anti-titin, anti-skeletal muscle, anti-RyR, anti-AchR and anti-LRP4) and compared detection of either of these autoantibodies between cancer patients with and without ICI-induced neuromuscular disease. Here, TTN is linked to myasthenia gravis.