Assessing Adherence to Cardiac Monitoring Guidelines in Trastuzumab-Treated Breast Cancer Patients: Insights From a Tertiary Hospital

INTRODUCTION: Breast cancer is a global health concern, with a significant portion of patients exhibiting human epidermal growth factor receptor 2 (HER2) overexpression. Trastuzumab is one of the pivotal therapies for HER2-positive breast cancer, but it carries the risk of cardiotoxicity. Guidelines for cardiac monitoring are essential to detect early signs of cardiotoxicity. However, adherence to these guidelines remains uncertain. METHOD: In this single-center retrospective cohort study, we analyzed data from 167 female patients diagnosed with HER2-positive breast cancer who were treated with trastuzumab. We meticulously assessed the level of adherence to cardiac monitoring guidelines and determined the incidence of trastuzumab-induced cardiotoxicity (TIC). Factors affecting adherence were subsequently investigated using appropriate statistical methods. RESULTS: Adherence to monitoring guidelines was only 31.7%. TIC incidence was 7.8%. Patients with concurrent use of cardiotoxic medications demonstrated higher adherence. A significant association was found between the number of trastuzumab doses and adherence. CONCLUSION: Adherence to monitoring guidelines was suboptimal. Those at a higher risk of cardiac issues showed greater adherence. Improved risk assessment methods are needed to individualize monitoring and intervention. Future research should focus on patient-centered, evidence-based monitoring to optimize the balance between cancer therapy and cardiac safety in the field of cardio-oncology.