Clinical characteristics and outcome of acute leukemia in Down syndrome pediatric patients: a single centre experience in Egypt

Background
Down syndrome (DS) is the most common chromosomal anomalies, associated with an increased risk of acute leukemia (AL). However, balancing curative therapy and potential toxicities is difficult in the treatment of DS children. We aimed to provide an illustrative study about disease characteristics and its outcome in this group of patients in our country.


Patients and methods
An institutional-based retrospective study including DS children with AL over 9 years, was conducted from January 2011 to December 2019. We collected all initial clinical and laboratory data, given treatment protocols, response to initial treatment, and patient outcomes in the form of overall survival (OS) and event-free survival (EFS).


Results
We collected 33 DS patients. Eight patients had acute myeloid leukemia, and one case had documented transient abnormal myelopoiesis, accounting for 27%, and 24/33 (73%) patients had acute lymphoblastic leukemia (ALL). The cumulative OS at the end of the study for the acute myeloid leukemia group was 37.5%, while the EFS was 37.5%. In the ALL group, the cumulative OS was 33.3% at the end of the study, while EFS was 29.2%. Initial white blood cells greater than or equal to 50 000/mm3 had a statistically significant negative prognostic impact on OS and EFS in ALL group.


Conclusion
AL in DS has specific features with lower OS and EFS than non-Down patients, mainly in low- and middle-income countries, caused by increased sensitivity to chemotherapy with a consequent increase in treatment-related mortality, emphasizing the importance of improving supportive care measures for such groups of patients.