Treatment of thymoma with immune checkpoint inhibitors increases the risk of muscle toxicity

An analysis of various registries and clinical trial data, carried out by an international team involving researchers from the Institute of Myology, revealed:

  • 1,495 cases of myocarditis with immune checkpoint inhibitors in the World Health Organization’s VigiBase registry, a rare (around 1%) but potentially serious adverse event,
  • a 10- to 30-fold greater risk of ICI myotoxicity in patients receiving this treatment for a thymus epithelial tumor (TET), compared with those treated for another form of cancer,
  • an earlier onset of myocarditis with ICI, and an increase in its severity, in TET patients,
  • a more frequent presence of anti-acetylcholine receptor antibodies (RACh) and thymus CT features (diameter, thickness, etc.) in cases of myocarditis under ICI.

A clinical, biological and radiological assessment of the thymus could thus have a predictive value for ICI myotoxicity.


Thymus alterations and susceptibility to immune checkpoint inhibitor myocarditis. Fenioux C, Abbar B, Boussouar S et al. Nat Med. 2023 Oct 26.