Cardiotoxicity of the adjuvant trastuzumab in a Saudi population: Clinical experience of a single institution

Abstract

Purpose: Adjuvant trastuzumab is currently an internationally standard for the treatment of localised breast cancer that over express HER2 with the most adverse effect being cardiotoxicity. We conducted this study to evaluate the cardiac safety of trastuzumab in clinical practice. Methods: This study is a retrospective observational single institutional study conducted in the Oncology Center of King Abdulla Medical City (KAMC), Makkah, Saudi Arabia, from June 2011 to January 2014. We evaluated the incidence of cardio toxicity and associated risk factors during adjuvant trastuzumab treatment. Results: Of 57 patients, 20 patients (35%) exhibited cardiotoxicity. About 14% of patients had drop of left ventricular ejection fraction (LVEF) below 50%, whilst 10% and 15% drop of LVEF below their baseline levels were found in 30% and 5% of patients, respectively. About 98.3% of our patients have completed treatment, of whom 21% had a provisional interruption because of a fall in LVEF. A definitive trastuzumab discontinuation has been made in 1.75% of cases because of a nonregressive reduction in LVEF. Analysis of risk factors related to trastuzumab cardio toxicity found that patients older than 40 years were more likely to develop cardio toxicity compared to those younger than 40 years. This difference was statistically significant (p = 0.042). Conclusion: In our study, the cardiac safety seems comparable with the literature data. Trastuzumab-related cardiotoxicity is manifested by an asymptomatic decrease in the LVEF and less commonly by clinical heart failure. Most instances are transient, asymptomatic and reversible.