Prevalence and significance of cytogenetic findings of acute lymphoblastic leukemia : experience at King Hussein Medical Center

Abstract EN

Objective : To determine the spectrum of cytogenetic abnormalities of acute lymphoblastic leukemia in children and adults at King Hussein Medical Center.

Methods : A retrospective review of raw bone marrow aspirate cytogenetic analysis reports was conducted at Princess Iman Research and Laboratory Sciences Center at King Hussein Medical Center during the period between Jan 2010 and Apr 2014.

A total of 97 patients were studied regarding: age, gender, and cytogenetic analysis.

The age was categorized into two groups (≤ 14 years as children group and > 14 years as adult group).

Descriptive analysis using frequencies was used to describe the study variables.

Results : Fifty-two (53.6 %) cases were males and 45 (46.4 %) were females.

Their ages ranged between six months and 72 years.

A total of 72 (74.2 %) patients were children and 25 (25.8 %) patients were > 14 years old.

Of all pediatric acute lymphoblastic leukemia cases, 52.8 % (38 cases) were negative for all the cytogenetic abnormalities, while 47.2 % (34 cases) revealed one or more cytogenetic abnormalities.

Translocation t (12;21), hyperdiploidy (> 50 chromosomes or DNA index > 1.16) were the predominant cytogenetic abnormalities in children with lymphoblastic leukemia.

In the adult lymphoblastic leukemia group, 68.0 % (17 cases) were negative for all the cytogenetic abnormalities, while 32 % (8 cases) had cytogenetic abnormalities.

Hyperdiploidy was the most common (20.0 %, 5 patients) followed by translocation t (9 ; 22) (8.0 %, 2 patients).

Conclusion : Distribution and patterns of chromosomal abnormalities of lymphoblastic leukemia differ between children and adults.

Translocation t (12 ; 21), hyperdiploidy and rearrangements / translocations involving the MLL gene at chromosome 11q23 were the most commonly encountered in children.

Hyperdiploidy was prevalent in adults, while no adult cases with 11q23 rearrangements or t (12 ; 21) were encountered.