Background: Down Syndrome (DS) is a predisposing syndrome for leukemia. Patients with Down syndrome (DS) have acute leukemia characterized by unique toxicity profiles and treatment responses. Achieving a balance between potential toxicities and curative treatments is challenging. The purpose of this research was to identify potential risk factors and the incidence of clinical cardiotoxicity following Anthracycline therapy in DS with acute leukemia.

Patients and methods: From January 2011 to December 2019, 32 pediatric patients with DS and acute leukemia were recruited for this retrospective study at Cairo University's National Cancer Institute (NCI). The study excluded patients above 18 years old, those who had already received treatment, and those with missing data. Cardiotoxicity was reported according to the Common Terminology Criteria of Adverse Events (CTCAE), version 5.0.

Results: Of the 32 individuals diagnosed with DS and acute leukemia, eight patients (25%) had acute myeloid leukemia (AML), 24 (75%) had acute lymphoblastic leukemia (ALL), and 18 (56%) had associated congenital cardiac defects (CHD). The median age was 3.25 years. All patients with AML had CHD, whereas 41.7% (10/24) of ALL patients had CHD. Clinical cardiotoxicity was reported in 16 patients (50%) and was more common in individuals with CHD compared to patients with structurally normal hearts, as 75% (12/16) of patients who had cardiotoxicity had concomitant CHD.

Conclusion: Leukemic patients with Down syndrome and congenital heart disease are more susceptible to Anthracycline-associated cardiotoxicity than patients with DS and structurally normal hearts.