Long-term cardiac outcomes following low-dose anthracycline exposure

Abstract

9519 Background: Pediatric cancer survivors treated with moderate-high dose (=250mg/m2) anthracycline therapy are known to be at risk for cardiac toxicity. It remains unclear what cardiac risk exists for survivors who received a low dose (<250mg/m2) therapy. Methods: Cardiac MRI and maximal VO2max testing were performed on young adult survivors of childhood acute lymphoblastic leukemia (ALL). MRI measurements included ejection fraction (EF), left ventricular (LV) mass, end diastolic volume (EDV), end systolic volume (ESV), and concentricity (LV mass/EDV). Survivors who were treated with low dose anthracycline (< 250mg/m2) were compared to those without anthracycline exposure. Spearman correlations and multivariable linear regression were used to examine the relationship between anthracycline dose and measures of cardiac function and cardiorespiratory fitness. Results: Sixty-seven survivors (mean age 23.9 ±5 years) participated, including 39 (58.2%) females. The mean interval from cancer diagnosis to study was 17.4 ± 6.6 years. The number of participants by cumulative anthracycline dose were 19 (28.4%) with no exposure, 28 (41.8%) with doses of 1–249mg/m2, and 20 (29.8%) with doses of =250mg/m2. When adjusted for age and race, there was not a significant difference in the cardiac MRI outcomes and VO2max levels between participants who received 1- 249mg/m2 of anthracycline versus those without anthracycline exposure. Conclusions: With continued use of anthracyclines at cumulative low doses, particularly in ALL standard risk trials, it is important to determine if there is a long-term cardiotoxicity. With a mean follow-up of 17 years, our data support the safety of low cumulative dose anthracycline. [Table: see text] No significant financial relationships to disclose.