A Retrospective Cytogenetic Abnormality in Pediatric Acute Lymphoblastic Leukemia: Report of 11 Years.

ABSTRACT

Background: Acute lymphoid leukemia (ALL) is the largest subset of hematologic malignancies, accounting for approximately 70%-80% of childhood leukemia, and is most common at age 4 years. The aim of this study was to define the frequency of chromosomal abnormalities in pediatric ALL. Materials and Methods: In this 11-year retrospective study, we investigated 99 patients which referred to our department due to ALL from 2010 to 2020. The age group of the patients ranged from 6 months to 14 years with a mean of 6.71 ± 4.09 years. Clinical and diagnostic findings were extracted from patients' medical records. Results: We showed cytogenetic abnormalities of 99 pediatric ALL patients, including 78 pre-B-ALL, 9 common B-ALL, and 12 T-ALL cases. The 5-year overall survival rate (OSR) and event-free survival (EFS) of all cytogenetic abnormalities (n = 99) were 48% and 43%, respectively. There was a significant relationship between the two cytogenetic abnormalities, hypodiploidy and t(9;22), with death (P < 0.05). On comparing the subjects with normal cytogenetics to the other cytogenetic abnormalities, EFS was significantly low for hypodiploidy (P = 0.0163, hazard ratio = 0.5308) and t(9;22) (P = 0.0131, hazard ratio = 0.4908), while other cytogenetic abnormalities did not have a statistically significant difference in EFS. Conclusions: Our results emphasized the importance of the cytogenetic findings in evaluating the survival outcomes, which allows identifying a variety of OSR and EFS, because some of the cytogenetic abnormalities may interfere with the death and prognosis.