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.

Glucosylsphingosine (lyso-Gb1) as a Biomarker for Monitoring Treated and Untreated Children with Gaucher Disease.

The role of glucosylsphingosine (lyso-Gb1), a downstream metabolic product of glucosylceramide, for monitoring treated and untreated children with Gaucher disease (GD) has not yet been studied. We reviewed the clinical charts of 81 children (<18 years), 35 with mild type 1 GD (GD1), 34 with severe GD1 and 12 with type 3 GD (GD3), followed at Shaare Zedek Medical Center between 2014-2018. Disease severity for GD1 was based on genotypes. Forty children (87%) with severe GD1 and GD3 received enzyme replacement therapy (ERT) compared to two children (6%) with mild GD1. Lyso-Gb1 measurements were conducted on dried blood spot samples taken at each clinic visit. Lyso-Gb1 levels were significantly lower in children with mild compared to severe GD1 (p = 0.009). In untreated children, lyso-Gb1 levels were inversely correlated with platelet counts. During follow-up, lyso-Gb1 increased in almost 50% of untreated children, more commonly in younger children. In treated children, lyso-Gb1 levels were inversely correlated with hemoglobin levels. The increase of lyso-Gb1 while receiving ERT, seen in eight children, was partly associated with compliance and weight gain. Lyso-Gb1 seems to be a useful biomarker for monitoring children with GD and should be included in the routine follow-up. Progressive increase in lyso-Gb1 levels in untreated children suggests ERT initiation.

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.

Distinct cytogenetic pathways of advanced-stage neuroblastoma tumors, detected by spectral karyotyping.

Molecular studies of advanced-stage neuroblastoma (NBL) have revealed a marked genetic heterogeneity. In addition to MYCN amplification and chromosome 1 short-arm deletions/translocations detected by conventional cytogenetics, application of fluorescence in situ hybridization has disclosed a high prevalence of 17q gain, whereas allelotyping and comparative genomic hybridization techniques also have revealed loss of 11q and of other chromosomal material. Using the recently developed technique of spectral karyotyping (SKY), we sought to refine the cytogenetic information, identify hidden recurrent structural chromosomal abnormalities, and compare them to the molecular findings. Thirteen samples of metaphase spreads from 11 patients with advanced-stage NBL were analyzed by SKY. Most of them were found to have complex karyotypes (more than three changes per metaphase) and complex unbalanced rearrangements. Recurrent aberrations leading to 17q gain, deletion of 1p, MYCN amplification, and loss of 11q appeared in 7, 4, 4, and 5 patients, respectively, in simple and complex karyotypes. Chromosome 3 changes and gain of 1q and 7q appeared in 6, 5, and 4 patients, respectively, in complex karyotypes only, reflecting later changes. A strikingly high prevalence of the unbalanced translocation der(11)t(11;17), leading to concomitant 11q loss and 17q gain in 4 patients, delineated a distinct cytogenetic group, none having 1p deletion and/or MYCN amplification. der(11)t(11;17) was associated with complex karyotypes with changes in chromosomes 3 and 7q. The 17q translocations with partners other than 11q were associated with 1p deletion and/or MYCN amplification. The distinct cytogenetic subgroups identified by SKY confirm and extend the recent molecular observations, and suggest that different genes may interact in the der(11)t(11;17) pathway of NBL development and progression.