Clinical characteristics and treatment outcome of childhood acute lymphoblastic leukemia in Saudi Arabia: a multi-institutional retrospective national collaborative study.
BACKGROUND
Treatment of childhood acute lymphoblastic leukemia (ALL) has been available in Saudi Arabia (SA) for over 30 years; however, only limited data have been published from there. This study was conducted to establish processes for collaborative data collection and provide clinical characteristics and outcome of children with ALL in SA.


METHODS
Clinical data for patients diagnosed from 2004 to 2008 were retrospectively collected at eight institutions and entered remotely into a custom-built database. Statistics regarding clinical and genetic characteristics and treatment outcome were calculated.


RESULTS
The 594 evaluable patients had a median age of 4.37 years and 56.4% were boys. Majority of patients had B-precursor ALL while 10.7% had T-ALL. CNS leukemia was present in 5.2% of patients. The distribution of common genetic abnormalities was similar to that reported from western populations, with 24.6% hyperdiploidy, 21% RUNX1-ETV6 positivity, 4.2% BCR-ABL1 positivity, and 2.5% with MLL gene rearrangement. Patients received risk-adapted therapy according to various protocols, although treatment strategies for the majority were similar. Five-year OS, RFS and EFS were 86.9%, 79.1%, and 73.3%, respectively. The OS for patients with pre-B ALL was significantly higher than for T-ALL (88.0% vs. 71.8%; P = 0.019, Log-Rank test). Patients with pre-B ALL categorized as low-risk by NCI/Rome criteria and those with hyperdiploidy had OS of 93.4% and 95.8%, respectively.


CONCLUSIONS
The characteristics of childhood ALL in SA are similar to those observed in developed countries. Future prospective studies utilizing unified national protocols are needed to further improve the outcome of our patients.
Department of Oncology, King Fahad National Guard Hospital/King Abdulaziz Medical City, Riyadh, Saudi Arabia.
Reem
R
Al-Sudairy
Abdullah
A
Al-Nasser
Abdulrahman
A
Alsultan
Ali
A
Al Ahmari
Ibraheem
I
Abosoudah
Reema
R
Al-Hayek
Talal
T
Al-Harbi
Fahad
F
Al-Manjomi
Musa
M
Al-Harbi
Hasna
H
Al-Ghamdi
Mohammed
M
Al-Shahrani
Asim F
AF
Belgaumi
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D016208:Databases, Factual; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics / Q000473:pathology / Q000628:therapy; D012189:Retrospective Studies; D012529:Saudi Arabia; D016896:Treatment Outcome
acute lymphoblastic leukemia; childhood; outcome