Adjuvant trastuzumab cardiotoxicity in patients over 60 years of age with early breast cancer: a multicenter cohort analysis.

BACKGROUND: Adjuvant Trastuzumab with chemotherapy is the gold standard for human epidermal growth factor receptor 2 (HER2)-positive early breast cancer (HER2+ EBC). Older patients have been largely under-represented in clinical trials, and few data on Trastuzumab cardiotoxicity have been reported in this subgroup. PATIENTS AND METHODS: Four hundred and ninety-nine consecutive HER2+ EBC patients were treated with adjuvant trastuzumab and chemotherapy (aTrastC) at 10 Italian institutions. We evaluated disease prevalence and patient characteristics in the patients older than 60 years of age (over-60), prevalence of aTrastC cardiotoxicity and risk factors.
RESULTS: There were 160 'over-60' patients (32%), in whom a higher prevalence of hypertension, diabetes, renal dysfunction, dyslipidemia and treatment with ACEi (40 versus 8%) and beta blockers (20 versus 8%) was found than in the younger patients (339 = 68%). Clinical heart failure occurred in 6% of the 'over-60' and in 2% of the younger patients. A reduction in left ventricular ejection fraction of >10 points was detected in 33% of the 'over-60' and in 23% of the younger patients (all P < 0.05). aTrastC was discontinued in 10% of the 'over-60' and in 4% of the younger patients (P = 0.003), restarted in 44% of the 'over-60' and in 58% of the younger women (P = ns).
CONCLUSION: In clinical practice, 32% of HER2+ EBC patients treated with aTrastC are 'over-60'. These patients have an increased cardiovascular risk profile and develop aTrastC cardiotoxicity commonly.