Poorer outcome of childhood acute lymphoblastic leukemia in the Bedouin population: A report from the Berlin-Frankfurt-Muenster-based Israeli national protocols.

BACKGROUND: Therapy outcomes for childhood acute lymphoblastic leukemia (ALL) had substantially improved in the last decades, but variability across racial and ethnic groups was identified in some clinical studies. In this study, we aimed to investigate whether such a difference in outcome is found in the diverse ethnicities in Israel as well. METHODS: A retrospective study was conducted among 1154 patients (855 Jews, 195 Muslims, 52 Bedouins, 26 Druze, and 26 others) aged 1 to 21 years, who were diagnosed with ALL between 1989 and 2011 and were treated according to the same Berlin-Frankfurt-Muenster-based Israel National Study protocols. RESULTS: Bedouins had a higher incidence of t(1;19) (16% vs 3% for non-Bedouins) and a lower incidence of high-hyperdiploidy (10% vs 25% for non-Bedouins) (P = 0.01). Five-year event-free survival (EFS) and overall survival (OS) were poorer for the Bedouins (60.3% ± 7.2% and 63.1% ± 7.2%, respectively) compared with the Jews, Muslims, and Druze (80.4% ± 1.4%, 77.3% ± 3.2%, and 84% ± 7.3%, respectively, for EFS [P = 0.02], and 86.3% ± 1.2%, 82.3% ± 2.9%, and 88.3% ± 6.4%, respectively, for OS [P = 0.002]). Adherence to intensive chemotherapy was similar between the Muslims and the Bedouins. CONCLUSIONS: Our findings suggest that the Bedouins, a highly inbred ethnic Arab people, may be considered a higher risk group that may need more intensive chemotherapy and/or supportive care in order to improve their outcome.

Extended triple intrathecal therapy in children with T-cell acute lymphoblastic leukaemia: a report from the Israeli National ALL-Studies.

Owing to the increased central nervous system (CNS) relapse risk in T-cell acute lymphoblastic leukaemia (ALL), it is unclear whether preventive cranial radiation (pCRT) can be safely omitted. In this study, pCRT was replaced by extended triple intrathecal therapy (TIT) in prednisone good early responders - medium-risk (MR) group, accounting for 76% of T-ALL patients. From 1989 to 2003, 143 T-ALL patients aged 1-18 years were enrolled in the Israel National Studies (INS) 89 (n = 84) and INS 98 (n = 59) trials, based on ALL-Berlin-Frankfurt-Munster (BFM) 86/90 and ALL-BFM 95 protocols, respectively. Five-year event-free survival (EFS) of the MR group in the INS 89 (n = 60) was 70 +/- 5.9% and the INS 98 (n = 43), 83.7 +/- 5.6% (P = 0.12); the cumulative incidence (CI) of any CNS relapse was 5.0 +/- 2.8% and 2.3 +/- 2.3% (P = 0.50), respectively. There was no difference in outcome between MR patients with a white blood cell count (WBC) >or=100 x 10(9)/l treated with extended TIT (n = 17) or pCRT (n = 10). For all T-ALL patients, 5-year EFS was 61.9 +/- 5.3% in INS 89 and 72.9 +/- 5.8% in INS 98, (P = 0.21); the CI of any CNS relapse was 7.1 +/- 2.8% and 1.7 +/- 1.7% (P = 0.142), respectively. Outcome of T-ALL MR patients given extended TIT in the context of BFM-based protocols with long-term follow-up appeared to be comparable to studies in which a larger proportion of patients was irradiated, and was associated with low risk of CNS relapse, regardless of the WBC.