Relapsed acute leukemia in children: Oman experience

Area of Science:

• Pediatric Oncology
• Hematology
• Cancer Epidemiology

Background:

• Acute leukemia (AL) is the most common childhood cancer in Oman, with acute lymphoblastic leukemia (ALL) comprising approximately 75% of cases.
• Sultan Qaboos University Hospital is the national referral center for pediatric leukemia, managing 128 cases between 1993 and 2003.

Purpose of the Study:

• To analyze the relapse patterns and outcomes of childhood acute leukemia in Oman.
• To classify relapses based on timing and site (bone marrow, extramedullary, or combined).

Main Methods:

• A retrospective review of 128 childhood acute leukemia cases diagnosed between January 1993 and January 2003.
• Diagnosis was confirmed via bone marrow aspirate with morphological and immunophenotypic classification.
• Relapse data was analyzed according to BFM group criteria and relapse site.

Main Results:

• Twenty-four cases (18.75%) relapsed during the study period.
• Relapse rates were 16% for ALL and 58.6% for acute myeloid leukemia (AML), with most AML cases relapsing early.
• Eleven patients experienced combined bone marrow and extramedullary relapses, frequently involving the central nervous system.

Conclusions:

• Relapse rates in Omani children with acute leukemia are comparable to international reports.
• The overall outcome for relapsed pediatric leukemia in this cohort is very poor, with only 6 of 24 relapsed patients surviving.
• Early relapse is common, suggesting a need for further research into genetic and molecular factors influencing clinical outcomes.