Outcome and Clinical Significance of Immunophenotypic Markers Expressed in Different Treatment Protocols of Pediatric Patients With T-ALL in Developing Countries.

BACKGROUND: T-cell acute lymphoblastic leukemia (T-ALL) accounts for about 15% of pediatric ALL. With wider use of intensive chemotherapy, the prognosis for childhood T-ALL has improved. Further gains in treatment outcome will likely require methods to identify patients who continue to fail on contemporary protocols. This study aimed to evaluate pediatric patients with T-ALL at 2 different Arabic cancer centers regarding their clinicopathologic, immunophenotypic, and cytogenetic features and outcome. PATIENTS AND METHODS: This retrospective study included all children with T-ALL treated between 2003 and 2013 at 2 oncology centers in the Middle East. Patients were divided into (group I) treated with Berlin-Frankfurt-Münster (BFM)-90 treatment protocol between February 2003 and June 2007 and (group II) includes all patients treated thereafter by the Total Therapy Study XIII protocol for high-risk ALL. RESULTS: This study included 103 patients with a median age of 8.9 years. The male to female ratio was 2.6:1. The median initial white blood cell count was 123 × 109/L. Central nervous system leukemia was detected in 15%. The early T-cell precursor (ETP)-ALL phenotype was found in 16.5%. The 5-year overall survival was 20.7% ± 67.5% and 72.9% ± 5.7% (P < .01); the 5-year disease-free survival was 47.1% ± 13.8% and 77.3% ± 6.0% (P = .023); and the 5-year event-free survival was 28.6% ± 12.1% and 71.1% ± 6.2% (P = .003) for group I and II, respectively. CONCLUSION: The outcome of patients with T-ALL significantly improved in patients who received the treatment protocol of ALL with high-risk criteria. This protocol eliminates the bad outcomes effect of several clinical and immunophenotypic markers. Patient with the ETP-ALL phenotype had a nonsignificant inferior outcome compared with the non-ETP-ALL group.

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. PROCEDURE: 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.