Troponin-to-Lymphocyte Ratio in ICI Associated Myocarditis: A Useful Marker with Limitations

Dear Editor,

We read with great interest the article by Chen et al. on the prognostic role of the troponin-to-lymphocyte ratio (cTn/ALC) in patients with immune checkpoint inhibitor (ICI) associated myocarditis. This complication, although infrequent, carries a disproportionately high risk of morbidity and mortality among cancer patients receiving immunotherapy. The authors should be commended for exploring a simple and widely available marker that reflects both myocardial injury and immune status. Such an approach is clinically attractive because both troponin and lymphocyte count are routinely measured, inexpensive, and easily standardized. Previous reports have already highlighted the prognostic role of troponin elevation and lymphocyte dynamics in ICI associated myocarditis,^– and the integration of these two markers into a composite index is a logical and potentially valuable step forward.

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