Myositis in cancer patients receiving immune checkpoint inhibitors: the ARON-MOUSEION-017 systematic review and meta-analysis

BACKGROUND Myositis may present as a treatment-related adverse events (TRAEs) during immune checkpoint inhibitor (ICI) therapy. In the ARON-MOUSEION-017 meta-analysis, we aimed to assess the frequency of myositis among cancer patients treated with ICIs.RESEARCH DESIGN AND METHODS The present systematic review and meta-analysis was registered in PROSPERO with id no. CRD420261278193. Embase, PubMed, Scopus and Web of Science databases were consulted, using Boolean terms and keywords ‘Immunotherapy,’ ‘Myositis’ and ‘Neoplasms.’RESULTS For myositis of any grade, thirteen studies were included suggesting heterogeneity across studies was high and statistically significant (p < 0.001; τ2 = 3.78; I2 = 95.3%, 95% CI [93.1%; 96.7%]), and the pooled proportion of patients affected of any-grade myositis treatment-related adverse events (TRAEs) was 4.2% (95% CI = [1.1%; 14.6%]).CONCLUSIONS ICI-myositis often appears in concomitance with other immune-mediated conditions, like myocarditis and myasthenia gravis. These concomitant syndromes are clinically relevant, since they are often associated with more severe disease courses and unfavorable outcomes increasing morbidity and mortality.