Troponin as a cardiotoxicity marker in breast cancer patients receiving anthracycline-based chemotherapy: A narrative review

The approach to breast cancer has changed in recent decades due to significant advances in screening, early diagnosis, and treatment; however, the risk of cardiovascular injury induced by chemotherapy has remained similar. Anthracyclines are the most common agents used in breast cancer treatment and may lead to cardiotoxicity, which appears to have a direct relationship with accumulated dose and duration of treatment. Therefore, the use of cardiac biomarkers derived from those used in cardiac disease diagnosis has been applied to the early identification, evaluation, and cardiotoxicity monitoring during chemotherapy. Cardiac troponins (cTn) have high specificities and high sensitivity in myocardial injury and are used in the diagnosis and risk stratification of acute coronary syndromes. cTn have been validated by clinical studies in the cardiotoxicity diagnosis and prognosis in patients treated with high doses of anthracyclines alone or in combination, mainly with trastuzumab. Thus, the identification of cardiotoxicity through cTn in the preclinical phase would be crucial for the application of preventive strategies. Here, we analyzed 23 cross-sectional, prospective and retrospective studies using cTn as the biomarker of cardiotoxicity in patients with breast cancer receiving treatment with anthracyclines. Studies showed that the association of cTn with different biomarkers can contribute to the early diagnosis of cardiotoxicity; however the main evidence is that low cTn levels is related to a better outcome with a good negative predictive value (NPV). In conclusion, different studies are still necessary for the adoption of cTn as a routine clinical biomarker in patients with breast cancer receiving anthracycline treatment.