Serum creatine kinase elevation following tyrosine kinase inhibitor treatment in cancer patients: Symptoms, mechanism, and clinical management.

Molecular targeted tyrosine kinase inhibitors (TKIs) have produced unprecedented treatment response in cancer therapy for patients harboring specific oncogenic mutations. While the TKIs are mostly well tolerated, they were reported to increase serum levels of creatine kinase (CK) and cause muscle metabolism-related toxicity. CK is an essential enzyme involved in cellular energy metabolism and muscle function. Elevated serum CK levels can arise from both physiological and pathological factors, as well as triggered by specific drug classes. The incidence of serum CK elevation induced by a few approved TKIs (brigatinib, binimetinib, cobimetinib-vemurafenib combination [Food and Drug Administration, United States]; aumolertinib, and sunvozertinib [only approved by National Medical Products Administration, China]) were over 35%. CK elevation-related symptoms include myopathy, myositis, inclusion body myositis (IBM), cardiotoxicity, rhabdomyolysis, rash, and acneiform dermatitis. High-level or severe symptomatic CK elevation may necessitate dose reduction and indirectly dampen TKI efficacy. This review presents an updated summary about the prevalence rate and recent research about mechanisms leading to TKI-induced serum CK elevation in cancer patients. The utility of monitoring serum CK levels for predicting TKI-induced adverse effects and their management will also be discussed.