Total XIII Research Articles

Outcome of Patients with Acute Lymphoblastic Leukemia in an Egyptian Institution with Limited Resources. January 2000 - August 2011

Introduction: Acute lymphoblastic Leukemia (ALL) is associated with distinctive biologic and clinical features. The diagnoses and treatments have encountered several challenges in rural area of developing countries populations.Objectives: To evaluate the response and outcome of children with newly diagnosed ALL to a protocol that was modeled after the St Jude total XIII and to assess its effectiveness and treatment obstacles in the population of a developing country.Methodology: A retrospective analysis of patients under the age of 20 treated in Pediatric Oncology department, Menia Oncology Center was conducted. The outcome is reported using descriptive measures. Estimates of Overall survival (OS) and Disease free survival (DFS) will be analyzed.Results: One hundred patients (median age 9 years, range 1 to 19 years) with newly diagnosed ALL were considered eligible between January 2000 and August 2011. Fifty-three (53%) patients were male. Initial risk stratification comprised of 28 % low risk and 71% high-risk patients. One patient was not evaluable due to early induction death. Median total leukocytic count (TLC) at presentation was 30.000/cc (range; 1.500 - 628.000/cc). Twenty-one patients had anterior mediastinal mass detected by chest x-ray. Diagnosis was confirmed by blood and bone marrow examination with Leishman stain, PAS, and Sudan Black. According to the French-American-British (FAB) classification, 96% of patients had L2 morphology. Immunophenotyping and cytogenetic analysis were not available. Central nervous system (CNS) disease at diagnosis was found in 2% of cases. Eighty-three cases achieved complete remission (CR) post induction therapy. At a median follow up of 29.7 months (range 0.1 to 130 months), 73/100 (73%) patients maintained complete remission (CR). Five patients relapsed, including hematological relapse in 4 patients and CNS relapse in 1 patient. Twenty-seven patients died during the period of follow up. Causes of death were as follows; Septicemia and multi-organ failure (n=17), Disease recurrence (n= 5), Methotrexate toxicity (n=3), and invasive fungal infections (n=2). The 5-year OS and DFS for the whole group were 69.3% and 69.9% respectively. On multivariate analysis, TLC >50.000/ cc was an independent factor of disease recurrence (P=0.02) and non-relapse mortality (P=0.01). Age >10 years at diagnosis was associated with borderline significant inferior OS (P=0.09) and DFS (P=0.08).Conclusions: This is one of the largest reports of newly diagnosed ALL in a rural area of a developing country. Major cause of death was attributed to uncontrolled infections. Insufficient resources (e.g. lack of immunophenotyping, unavailable cytogenetics, limited supportive care, and absence of methotrexate level data) adversely affect the outcome. Further studies must be done to adequately report experiences of cancer centers in the developing world after adopting United States inspired protocols. DisclosuresNo relevant conflicts of interest to declare.

Genome-wide analysis links NFATC2 with asparaginase hypersensitivity

AbstractAsparaginase is used to treat acute lymphoblastic leukemia (ALL); however, hypersensitivity reactions can lead to suboptimal asparaginase exposure. Our objective was to use a genome-wide approach to identify loci associated with asparaginase hypersensitivity in children with ALL enrolled on St. Jude Children's Research Hospital (SJCRH) protocols Total XIIIA (n = 154), Total XV (n = 498), and Total XVI (n = 271), or Children's Oncology Group protocols POG 9906 (n = 222) and AALL0232 (n = 2163). Germline DNA was genotyped using the Affymetrix 500K, Affymetrix 6.0, or the Illumina Exome BeadChip array. In multivariate logistic regression, the intronic rs6021191 variant in nuclear factor of activated T cells 2 (NFATC2) had the strongest association with hypersensitivity (P = 4.1 × 10−8; odds ratio [OR] = 3.11). RNA-seq data available from 65 SJCRH ALL tumor samples and 52 Yoruba HapMap samples showed that samples carrying the rs6021191 variant had higher NFATC2 expression compared with noncarriers (P = 1.1 × 10−3 and 0.03, respectively). The top ranked nonsynonymous polymorphism was rs17885382 in HLA-DRB1 (P = 3.2 × 10−6; OR = 1.63), which is in near complete linkage disequilibrium with the HLA-DRB1*07:01 allele we previously observed in a candidate gene study. The strongest risk factors for asparaginase allergy are variants within genes regulating the immune response.

Genetic Variation in NFATC2 Is Associated with a Higher Risk of Asparaginase Allergy

Asparaginase is an important drug for the treatment of acute lymphoblastic leukemia (ALL); however, hypersensitivity reactions to asparaginase can lead to suboptimal asparaginase exposure and to a higher risk of disease recurrence. Factors influencing the frequency of asparaginase hypersensitivity include asparaginase formulation, the schedule of asparaginase administration, and concurrent chemotherapy. In addition, using a candidate gene approach, our group previously identified a genetic association between HLA-DRB1*07:01 and asparaginase hypersensitivity in patients of European ancestry.[PMID 24970932] The objective of our current study was to use a genome-wide approach to identify additional genetic loci associated with hypersensitivity and to assess the relative importance of HLA-DRB1 as a genetic risk factor.Asparaginase hypersensitivity was assessed in children with ALL enrolled on SJCRH protocols Total XIIIA (n = 154), Total XV (n = 498) and Total XVI (n = 271) or Children’s Oncology Group (COG) protocols POG 9906 (n = 222) and AALL0232 (n = 2,163). Patients enrolled on protocols Total XIIIA, Total XV and POG 9906 received native E. coli asparaginase during treatment, whereas patients on Total XVI and AALL0232 received PEGylated E. coli asparaginase. Hypersensitivities were graded according to the NCI common toxicity criteria, and reactions of grade 2 and above were considered cases. Germline DNA was genotyped using the Affymetrix 500K, Affymetrix 6.0, or the Illumina Exome Beadchip array. Univariate analysis of risk factors associated with asparaginase hypersensitivity using the combined cohort of patients (n = 3,308) identified a significant positive association with treatment arm (P < 2.2x10-16; highest risk in patients enrolled on Total XV), native E coli asparaginase formulation (P < 2.2x10-16), age < 10 years (P = 3.3x10-4), male gender (P = 0.06), and racial ancestry (P = 2.1x10-4; highest risk among African ancestry). In multivariate analysis, treatment arm (P < 2.2x10-16), gender (P = 0.04), racial ancestry (P = 0.07), and ALL lineage (P = 0.003) remained significant risk factors.A multivariate logistic regression model adjusted for treatment arm, racial ancestry, gender, age, and ALL lineage was used to identify genomic variants associated with asparaginase hypersensitivity in the combined patient cohort. The minor allele of an intronic polymorphism in NFATC2 (rs6021191) was associated with hypersensitivity at the genome-wide significance threshold (P = 2.6x10-8, OR = 3.17). The minor allele frequency (MAF) for the NFATC2 high-risk variant was highest in non-European ancestries (MAFEuropean = 0.001, MAFAfrican = 0.142, MAFHispanic = 0.043, MAFAsian = 0.151, MAFOther = 0.034). Using RNA-seq data available from the ALL tumor samples of 65 SJCRH patients, we found that patients carrying the variant had higher expression of NFATC2 compared to non-carriers (P = 1.0x10-3). NFATC2 is known to play a critical role in inducing T-cell gene transcription during immune responses.The strongest association detected using SNPs from the Illumina Exome array was found in HLA-DRB1 (rs17885382, P = 4.0x10-6, OR = 1.65), and the SNP is in near complete linkage disequilibrium with the HLA-DRB1*07:01 allele, which we previously found associated with asparaginase hypersensitivity. A gene-level analysis was performed using SNP-set Kernel Association Test (SKAT), and the gene with the strongest association with hypersensitivity was PPT2, located in the HLA class III region on chromosome 6 (P = 3.70x10-6). To determine potential biological pathways differentially represented by the genes identified by our analysis, we used Ingenuity Pathway Analysis on the top 1% of genes associated with hypersensitivity as identified by our single SNP (68 genes) and gene level analysis (18 genes). We found an enrichment of genes (8 out of 21 genes, P = 2.6x10-5) within the top network involved in humoral immunity, suggesting that other genes regulating immune responses may also contribute to the risk of developing asparaginase hypersensitivity.In conclusion, the top inherited genetic loci (NFATC2, HLA-DRB1*0701, PPT2) associated with asparaginase hypersensitivity are directly involved in human immune response, and pathway analysis suggests that inherited variations in other genes involved in humoral immunity likely play a role in the development of asparaginase hypersensitivity. DisclosuresEvans:St. Jude: In accordance with institutional policy (St. Jude), I and/or my spouse have in the past received a portion of the income St. Jude receives from licensing patent rights related to TPMT polymorphisms as clinical diagnostics. Patents & Royalties. Relling:St. Jude: In accordance with institutional policy (St. Jude), I and/or my spouse have in the past received a portion of the income St. Jude receives from licensing patent rights related to TPMT polymorphisms as clinical diagnostics. Patents & Royalties.

HLA-DRB1*07:01 Is Associated With Asparaginase Allergies In Children With Acute Lymphoblastic Leukemia

HLA-DRB1*07:01 Is Associated With Asparaginase Allergies In Children With Acute Lymphoblastic Leukemia

Lack of Prognostic Significance of Absolute Lymphocyte Count After Intensive Induction Therapy in Childhood Acute Lymphoblastic Leukemia

Abstract 4909 Introduction:Previous work has shown that the function and number of lymphocytes are vital for the patient's immune system to mount an effective response against cancer cells. Multiple recent studies have demonstrated the prognostic value of absolute lymphocyte count (ALC) in a wide range of malignancies. In children with acute lymphoblastic leukemia (ALL), ALC during induction chemotherapy have been shown to be an independent predictor of adverse outcome, even in the era of minimal residual disease (MRD). Most of the previous studies used Children Oncology Group (COG) based regimens with 3 or 4 drugs induction. We hypothesized that with more intensive induction regimens with 5 or 7 drugs, ALC would lose its prognostic value due to more intensive chemotherapy induced leukopenia. Patients/methods:We reviewed 136 Jordanian pediatric patients (Arabic ethnicity) with newly diagnosed ALL, age 1–18 years, from 2007 to 2009. The patients were treated at a single institution on modified St. Jude total XIII and VX protocols, with a median follow up of 35 months (range: 2–54 months). The induction phase was composed of 7 drugs regimen. Variables analyzed included ALC at diagnosis, day15, day 36 end of induction chemotherapy and at time of post induction marrow recovery, white blood cells at diagnosis, age at diagnosis, gender, immunophenotype, cytogenetics, risk group and MRD status at end of induction. ALC at each time-point was evaluated for prognostic ability by univariate and multivariate analysis. Results:We found that ALC at day15, day 36 end of induction chemotherapy and at time of post induction marrow recovery failed to have any prognostic effect on event-free survival (EFS) or overall survival (OS). We analyzed ALC as continuous and dichomatous variable, but without any prognostic significance. In contrast to our hypothesis, children with ALL intensive induction regimen did not have profound lymphopenia, with ALC day15 median of 1260 cells/ml (range: 0–9450), ALC day36 median of 866 (range: 100–3476), and ALC (post induction marrow recovery) median of 1145 cells/ml (range: 85–9676). Our cohort confirmed several known prognostic factors in childhhod ALL. For EFS outcome we found MRD35, age, phenotype and risk group to have a significant prognostic effect with P values of (0.016, 0.005, 0.006, 0.001) respectively. For OS outcome we found both age and phenotype to have a significant prognostic P value of (0.006 and <0.001) respectively. Conclusions:In this study we failed to replicate the previous work that showed the independent prognostic value of ALC during induction therapy in childhood ALL. In contrast to our hypothesis, the reason for the lack of significance was not due to more profound lymphopenia. The lack of ALC prognostic significance in our cohort could be protocol related or patient population (ethnicity) related. Further studies are needed in children with ALL with different ethnic backgrounds to validate the previous work regarding ALC significance before its incorporation in ALL prognostic models, especially in middle or low income countries. Disclosures:No relevant conflicts of interest to declare.

ETV6-RUNX1-positive childhood acute lymphoblastic leukemia: improved outcome with contemporary therapy

ETV6-RUNX1 fusion is the most common genetic aberration in childhood acute lymphoblastic leukemia (ALL). To evaluate whether outcomes for this drug-sensitive leukemia are improved by contemporary risk-directed therapy, we studied clinical features, response and adverse events of 168 children with newly diagnosed ETV6-RUNX1-positive ALL on St Jude Total Therapy studies XIIIA (N=36), XIIIB (N=38) and XV (N=94). Results were compared with 494 ETV6-RUNX1-negative B-precursor ALL patients. ETV6-RUNX1 was associated with age 1-9 years, pre-treatment classification as low risk and lower levels of minimal residual disease (MRD) on day 19 of therapy (P<0.001). Event-free survival (EFS) or overall survival (OS) did not differ between patients with or without ETV6-RUNX1 in Total XIIIA or XIIIB. By contrast, in Total XV, patients with ETV6-RUNX1 had significantly better EFS (P=0.04; 5-year estimate, 96.8±2.4% versus 88.3±2.5%) and OS (P=0.04; 98.9±1.4% versus 93.7±1.8%) than those without ETV6-RUNX1. Within the ETV6-RUNX1 group, the only significant prognostic factor associated with higher OS was the treatment protocol Total XV (versus XIIIA or XIIIB) (P=0.01). Thus, the MRD-guided treatment schema including intensive asparaginase and high-dose methotrexate in the Total XV study produced significantly better outcomes than previous regimens and demonstrated that nearly all children with ETV6-RUNX1 ALL can be cured.

Study of the pharmacokinetic and pharmacogenetic contribution to the toxicity of high-dose methotrexate in children with acute lymphoblastic leukemia

Methotrexate inhibits the conversion of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate by methylenetetrahydrofolate reductase (MTHFR). MTHFR has a common functional polymorphism C677T. The present study aimed to investigate the prevalence of MTHFR polymorphisms in Egyptian children with ALL and the relation to MTX-related toxicity, relapse, and MTX pharmacokinetic parameters. Forty patients with ALL were included in the study. They were treated according to ALL-NCI total XIII protocol. MTX-related toxicity and MTX pharmacokinetic parameters were assessed during therapy. MTHFR genotyping was done with a PCR-based restriction fragment length polymorphism assay, and MTX pharmacokinetic parameters were assessed by HPLC. The MTHFR C677T polymeric allele frequencies were 55, 35, and 10% for CC, CT, and TT genotypes, respectively, among the studied patients with ALL. MTX therapy was significantly associated with toxicity signs in TT genotype: elevated transaminases (P < 0.0001), elevated serum alpha 1-microglobulin protein (P < 0.0001), anemia (P < 0.0001), neutropenia (P < 0.0001), thrombocytopenia (P < 0.0001), and elevated CSF-β-glucuronidase activity (P < 0.0001). Patients with TT genotype showed significant increase in MTX t(½) and AUC (P < 0.0001), while MTX elimination rate and total body clearance were significantly decreased (P < 0.0001 and P < 0.05, respectively) compared with CC genotype. The TT genotype was significantly associated with relapse in 2 years in 50% compared with 28.57% in CT and 13.64% in CC alleles. The overall 2-year survival was significantly lower in TT genotype (50%) compared with CC genotype (90.91%; P = 0.01). MTHFR TT genotype is significantly associated with increased toxicity during methotrexate therapy as well as increased relapse rate in pediatric patients with ALL. In future, MTX dose adjustment in ALL treatment protocols should be considered based on patient's genotype.

Treatment‐related mortality in children with acute lymphoblastic leukemia in Central America

The objectives of this study were to describe the incidence, timing, and predictors of treatment-related mortality (TRM) among children with acute lymphoblastic leukemia (ALL) in El Salvador, Guatemala, and Honduras. Patients aged <20 years who were diagnosed with ALL between January 2000 and March 2008, who received treatment in any of the 3 countries, and who started induction chemotherapy were included in the study. Almost all patients were treated on the El Salvador-Guatemala-Honduras II protocol, which was based on the St. Jude Total XIII and XV protocols. Biologic, socioeconomic, and nutritional variables were examined as predictors of TRM. Of 1670 patients, TRM occurred as a first event in 156 children (9.3%); TRM occurred during remission induction therapy in 92 of 156 children (59%), between remission induction and maintenance therapy in 27 of 156 children (17%), and during maintenance therapy in 37 of 156 children (24%). Although the TRM rate decreased in patients who were diagnosed after July 1, 2004 (11.2% vs 7.9%; P = .02), the rate of induction death did not change (5.2% vs 5.8%; P = .58). Independent predictors of induction death included higher risk ALL (odds ratio [OR], 1.84; 95% confidence interval [CI], 1.03-3.27; P = .04), lower initial platelet counts (OR per 10 × 10(9) /L, 0.94; 95% CI, 0.89-0.98; P = .005), and longer travel time to the clinic (OR, 1.06 per hour; 95% CI, 1.01-1.14; P = .03). In Central America, TRM remains an important cause of treatment failure in children with ALL. A large proportion of TRM occurs in maintenance, although this proportion has decreased over time. Supportive care interventions should especially target children who present with low platelet counts. Further study on transfusion ability and the location of induction deaths is required.

Excellent Outcome for ETV6/RUNX1-Positive Childhood Acute Lymphoblastic Leukemia (ALL) with Contemporary Therapy

AbstractAbstract 495The t(12;21)(p13;q22) translocation causes the fusion of the ETV6 and RUNX1 genes and occurs in approximately 25% of cases of childhood B-precursor ALL. The presence of ETV6/RUNX1 has been associated with a lower rate of relapse in multiple studies. However, it is not clear whether the ETV6/RUNX1 fusion retains independent prognostic significance in the context of current risk-adapted therapy and whether the outcome of these children can be further improved.We studied clinical features, treatment response and adverse events of 168 children with newly diagnosed ETV6/RUNX1-positive B-precursor ALL enrolled in St Jude Total Therapy studies XIIIA (1991-1994; N=36), XIIIB (1994-1998; N=38) and XV (2000-2007; N=94). Results were compared to those of 495 ETV6/RUNX1-negative patients with B-precursor ALL. Total XV study used levels of minimal residual disease (MRD) during treatment for risk assignment.Presence of ETV6/RUNX1 was significantly related with age 1–9 years old (p<0.001), lower prevalence of central nervous system (CNS) disease at diagnosis (p<0.001) and classification as low-risk ALL (p<0.001). ETV6/RUNX1 patients had significantly lower rates of MRD positivity on day 19 (p<0.001) and day 46 of remission induction therapy (p=0.01) than non ETV6/RUNX1 patients. Event-free survival (EFS) did not differ between patients with or without ETV6/RUNX1 in Total XIIIA (p=0.14; 5-year EFS 86.1 ± 5.7% versus 75.6 ± 4.8%) or XIIIB (p=0.76; 5-year EFS 84.1 ± 6.8% versus 81.2 ± 3.8%). Likewise, overall survival (OS) did not differ among patients treated in either Total XIIIA (p=0.41; 5-year OS 88.9 ± 5.2% versus 83.3 ± 4.2%) or Total XIIIB (p=0.67; 86.5 ± 5.6% versus 85.0 ± 3.5). By contrast, patients with ETV6/RUNX1 ALL had significantly better EFS (p=0.008) and marginally better OS (p=0.057) than those without ETV6/RUNX1 in Total XV; 5-year EFS estimate was 97.6± 2.8% versus 86.0 ± 3.3% for patients without the fusion and 5-year OS was 98.9 ± 1.8% versus 93.3 ± 2.4%. Overall, among 168 patients with ETV6/RUNX1 ALL, there were 17 treatment failures, including 2 deaths in complete remission, 6 secondary malignancies (4 in Total XIIIA and 2 in Total XIIIB) and 9 relapses (6 hematologic, 1 combined hematologic and CNS and 2 isolated CNS relapses). Three relapses occurred during or within 6 months of completion of therapy while 6 occurred later. The median time to relapse was 38 months (range 6–139 months) as compared to 36.5 months (range 3–119 months) in ETV6/RUNX1-negative patients (p=0.28). In the most recent Total XV study, the only causes of treatment failure were 2 hematologic relapses. Within the ETV6/RUNX1 group, age, gender, race, presenting leukocyte count, CNS status, risk group and even MRD at day 19 and day 46 were not associated with 5-year EFS or OS. Only treatment protocol, i.e. Total XV (versus Total XIIIA or XIIIB) was significantly associated with improved EFS (p=0.03) and OS (p=0.04) (Figure 1). With the Total XV treatment strategy, conventional risk factors such as age and leukocyte count did not have prognostic significance among patients with ETV6/RUNX1-positive ALL. In this protocol, there were 5 ETV6/RUNX1 patients who were ≥10 years old and 17 who were 1–9 years old and had a leukocyte count ≥50 × 109/L at presentation with a good MRD decline (<1% on Day 19 and <0.01% on day 46). These patients received lower-risk therapy and none of them have relapsed to date. The Total XV regimen intensified asparaginase, dexamethasone (post-remission) and vincristine; drugs which are known to be especially cytotoxic to ETV6/RUNX1 lymphoblasts in vitro. Patients on Total XV might have also benefited from the higher doses of methotrexate administered during the consolidation phase, as ETV6/RUNX1 lymphoblasts accumulate lower amounts of methotrexate polyglutamates. In addition, measures such as avoiding cranial radiotherapy and limiting the use of epipodophyllotoxins and alkylating agents led to decreased adverse events like secondary malignancies for all patients.In conclusion, stringent risk-directed therapy featuring intensive asparaginase, dexamethasone and high-dose methotrexate resulted in excellent outcome for children with ETV6/RUNX1 ALL.Kaplan-Meier Estimates of EFS and OS in ETV6/RUNX1-positive Patients by Study. [Display omitted] Disclosure:Bhojwani:MedImmune: Research Funding. Sandlund:Seattle Genetics: Research Funding. Jeha:Genzyme: Honoraria, Research Funding. Relling:St. Jude Children's Research Hospital: Employment, Patents & Royalties; Enzon Pharmaceuticals: Research Funding. Pui:EUSA Pharma: Honoraria; Enzon: Honoraria; Sanofi-Aventis: Honoraria.

Delayed Recognition of Intrathecal Methotrexate Overdose

A 10-year-old girl who presented to our hospital was diagnosed as having B-precursor cell acute lymphoblastic leukemia. St Jude's Total XIII protocol was started. In the second block of the consolidation phase, 10 hours after triple intrathecal treatment, we realized that instead of 12 mg, 120 mg of methotrexate had accidentally been given. Although the patient had no symptoms 10 hours after intrathecal treatment, to prevent the possible neurotoxic effects of methotrexate, a cerebrospinal fluid exchange was performed. Simultaneously, systemic dexamethasone and calcium folinic acid were given. At the time of this writing (2 y), the patient has had no symptoms and has continued on the chemotherapy protocol as planned. Administration of high-dose intrathecal methotrexate may not lead to symptoms, as was the case in our patient. This may be related to individual variations in cerebrospinal fluid dynamics and drug metabolism.

Outcomes of Children with Acute Lymphoblastic Leukemia Treated with 2 Consecutive Protocols: Ramathibodi Hospital Experience

We determined the outcomes and prognostic factors of children (age, 0.8 to 14.8 years) with acute lymphoblastic leukemia (ALL) treated with 2 consecutive protocols between 1997 and 2008. The risk classification was followed NCI criteria. One hundred and one patients, (60 males and 41 females), were enrolled to the first protocol (modified St Jude Total XIII) (1997–2003). Ninety seven patients (96%) of these 101 patients achieved remission after induction. The event free survival (EFS) rates were 90.1 ± 3%, 85 ± 3.6%, and 83.8 ± 3.7%, and the cumulative risk of CNS relapse were 2.1 ± 1.5%, 3.2 ± 1.8%, and 3.2 ± 1.8%, at 3, 5, and 10 years, respectively. The median follow-up time for patients remaining free of adverse events was 6.8 years (4.2–10.3 years). The adverse prognostic factors included obesity (p =0.013), high risk group (p= 0.012), minimal residual leukemia (MRD) presence (> 0.01%) on day 15 of induction (p <0.001) and sepsis during treatment (p= 0.003). For the second protocol (modified St Jude Total XV) (2004–2008), 80 patients, 43 males and 37 females, were enrolled. Seventy nine (98.8%) of these 80 patients achieved remission after induction. The EFS rates were 92.1 ± 3.1% and 88.9 ± 3.7% at 1 and 3 years, respectively. The median follow-up time was 2.6 years (0.1–4.3 years) without evidence of CNS relapse. The adverse prognostic factor included mucositis during treatmenrt (p = 0.014). The EFS rates up to 85% in childhood ALL treated with two consecutive protocols attest the effectiveness of risk-adaptive therapy and multidisciplinary approach. Regarding to the second protocol, the efficacy of intensive systemic and intrathecal chemotherapy further supports the probability of eliminating cranial radiation and early therapeutic intervention on patients with persistent MRD leading to improve outcome overall, irrespective of patient's risk groups. Further studies on pharmacogenetic, genetic and proteomic profiles of leukemic cells ascertain the precise risk classification and treatment regimen of childhood ALL in the future.

Genomics of Childhood Leukemias: The Virtue of Complexity

Genomics of Childhood Leukemias: The Virtue of Complexity

The rate of hepatitis B and C virus infections and the importance of HBV vaccination in children with acute lymphoblastic leukemia

The aim of the study was to evaluate the rate of hepatitis B and C virus infection and emphasize the importance of hepatitis B virus (HBV) vaccination in leukemic children. One hundred and sixty children who were treated for acute lymphoblastic leukemia (ALL) at Hacettepe University Faculty of Medicine, Pediatric Hematology Unit were included in the study. They were 71 (44.4%) girls and 89 (55.6%) boys with a mean age of 6.45 +/- 3.87 years. Of these 160 children, 22 (13.8%) were anti-HBs-positive and 138 (86.2%) were anti-HBs-negative at the diagnosis of ALL. Among the 138 anti-HBs-negative children, 67 (41.9%) were vaccinated for HBV during maintenance chemotherapy, and 71 (44.3%) could not be vaccinated. Two (2.9%) vaccinated and 22 (30.9%) unvaccinated children developed HBV infection during the follow-up period (P < 0.001). Among 160 children treated for ALL, 24 (15.0%) had HBV, three (1.9%) had hepatitis C virus (HCV) infections, and 29 (18.1%) had toxic hepatitis. The majority of patients with HBV or HCV infections had high risk (HR) protocol, whereas most of the patients with toxic hepatitis had low risk (LR) protocol, especially St Jude Total XIII LR protocol. Viral hepatitis and toxic hepatitis were observed more commonly in the HR and LR group, respectively, of ALL patients. This could be explained by intensive chemotherapy and more heavy blood product administration in the HR group and the chemotherapeutic agents of methotrexate and 6-mercaptopurine, basic drugs used in the LR group. In respect to protection from these complications, periodical liver function tests, serological tests for HBV and HCV, and vaccination for HBV should be performed for all children with ALL.

Can Renal Leukemic Infiltration Cause Hypertension in Children?

Out of 334 children with acute lymphoblastic leukemia who were treated with St Jude Total XI and Total XIII chemotherapy protocols were investigated and 21 (6.3%) were hypertensive. The incidence of tumor lysis syndrome was higher in the hypertensive group than in the nonhypertensive group (28.6% vs. 11.5%) (P = 0.035). There were no differences between patients treated with high-dose methylprednisolone and prednisolone St Jude Total XI and Total XIII, St Jude Total XIII LR and St Jude Total XIII HR groups in respect of the above-mentioned parameters. Central nervous system involvement, skeletal system involvement, abdominal lymphadenopathy, elevated lactate dehydrogenase and leukocyte count, French-American-British types and immunophenotypes were not found to be statistically significant to the development of hypertension (P > 0.05). We found that renal leukemic infiltration is a risk factor in hypertension development (P = 0.04) and hypertension is a risk factor for renal parenchymal disorder in the follow-up period (P = 0.0001). Six patients presenting with hypertension in the first week of disease therapy were evaluated for renal parenchymal disorder and glomerular filtration rate abnormality in the follow-up period. Glomerular filtration rate abnormality was found in 1 and renal scintigraphic dimercaptosuccinic acid abnormalities (reduced uptake and dilated hypoactivity) were found in 4 patients. Hypertension was also found to be a risk factor for renal parenchymal disorder in the follow-up period.

The Retrospective Analysis of Pediatric Acute Leukemia Cases between 1980–2003: Hacettepe Experience.

Leukemia constitutes 25–30% of all pediatric malignancy cases. The epidemiologic and demographic characteristics of this group of patients are important not only for determination of the prognostic factors, but also the risk factors. In this study, 683 patients under 16 years of age who were diagnosed with acute lymphoblastic leukemia (ALL) and acute myeloblastic leukemia (AML) between January 1980-July 2003 in Hacettepe University, Pediatric Hematolgy Division are analyzed retrospectively. Besides the epidemiologic characteristics including age, sex, geographic distiribution; the type of disease, clinical presentation, physical examination and laboratory findings on admission and the survival and prognosis relationships are also evaluated in order to determine the disease properties of our country. ALL patients have recieved St. Jude Total XI until 1997, and after 1997 they are treated by St. Jude Total XIII protocol. AML patients have been treated by AML 1995 and AML 1998 protocols. The study group includes 548 (80.2%) ALL and 135 (19.8%) AML cases. Two thirds of the all acute leukemia cases are males in both ALL and AML cases. The median age at diagnosis is 62 months for ALL and 108 months for AML patients. ALL is more common among 1–5 year old group; AML is more common among adolescent age group. The incidence of hematologic malignancies increases suddenly in 1997 and 1998 and then showes a decline later. The hematologic malignancy cases who have been admitted to our clinic is most commonly living in the northern and southeastern parts of Turkey. 50% of ALL and AML patients presents with the complaints of fever and pallor. Bone pain is significantly more common in ALL patients. Median time between onset of syptoms and diagnosis is 30 days for both ALL and AML patients. Lymphadenopathy is present in almost half of ALL and AML patients at diagnosis. Hepatomegaly (72.4% vs 50.4%) and splenomegaly (53.8% vs 36.3%) are more commonly observed in ALL then AML patients (p<0.001). The central nervous system (CNS) involvement is present in 5.8% of ALL and 5.9% of AML patients. There is no statisticaly significant difference between ALL and AML patients in terms of bone, mediastinial and CNS involvements. The most common cytogenetical abnormality in ALL patients is hypodiploidy. 25.4% of ALL and 43.7% of AML patients have relapsed subsequently. The most common type of relaps is seen in bone marrow in both ALL and AML cases, however CNS relaps is seen more commonly among ALL patients (31% vs 4%). Fatality rates of ALL and AML are 20.1% and 56.3%, respectively. The fatality rate of AML is significantly higher than ALL. The CNS involvement at diagnosis and sex have no influnce on the fatality rates; on the other hand the presence of relaps for ALL and AML groups and L3 subtype, being less then 1 year old at diagnosis for ALL cases have a negative effect on fatality rates. Also the fatality rates of ALL patients who have been diagnosed before 1997 and recieved St. Jude Total XI protocol has higher fatality rates then who have been diagnosed after 1997 and recieved St. Jude Total XIII (23.3% vs 14.1%). The collection of the cancer data throughout the country is crucial for the determination of the distribution and risk factors of our country. The best way of cancer data collection is development of cancer recording systems and analyzing these data for the determination of distribution and risk factors of patients with hematologic malignancies.

Gene Expression Profiles Distinguish Children Who Develop Therapy-Related Myeloid Leukemia.

In children with acute lymphoblastic leukemia (ALL), failure due to therapy-related myeloid leukemia (t-ML) is a devastating complication. Using a target gene approach, only a few host genetic risk factors for t-ML have been defined. Microarray analysis of gene expression allows for a more genome-wide approach to identify possible genetic risk factors for t-ML. We assessed gene expression profiles (12625 gene probe sets) using oligonucleotide-based arrays in diagnostic ALL blasts from 228 children treated on St. Jude ALL protocols (Total XIII) that included etoposide; 13 of these children developed t-ML. A group of 83 probe sets were significantly related to the time-dependent risk of t-ML, with principal component analysis plot (right panel) separating patients who developed t-ML from the others. Hierarchical clustering of the 83 probe sets grouped patients into 3 clusters (n=163, n=52, n=13), with the cumulative incidence of t-ML being significantly higher in the last cluster (p < 0.0001, left panel) compared to those of the other gene-expression-defined clusters. [Display omitted] A permutation test indicated that probe sets selected by chance are unlikely to obtain the observed distinct clusters (p=0.045). Distinguishing genes included transcription-related oncogenes (v-Myb, Pax-5), cyclins (CCNG1, CCNG2 and CCND1) and Histone H4. Common transcription factor recognition elements among similarly up- or down-regulated genes included several involved in hematopoietic differentiation or leukemogenesis (Maz, PU.1, FOXO4). This approach has identified several genes whose expression differentiates patients at risk of t-ML, and provides targets for assessing the germline predisposition to leukemogenesis.

Acute Lymphoblastic Leukemia Presenting as Cutaneous Involvement

Primary cutaneous involvement in B-cell lymphoblastic leukemia is rare in childhood. We present a case of 2-year-old girl admitted to our hospital because of left scapular skin lesion and left axillary mass. She was looked pale and weak. Left axillary lymph node pachage of 5 cm diameter and left scapular skin lesion was revealed by physical examination. Complete blood count revealed 124.000/mm3 white blood cell count. Peripheral blood smear showed 99% lymphoblasts. Bone marrow aspiration revealed 95% blastic cells with immunophenotype and morphological characteristics of pre-B type acute lymphoblastic leukemia with L1 subtype. ALL St Jude Total XIII remission induction treatment protocol was started. Skin lesion disappeared after 15th day of the cytotoxic therapy. On the follow up, she was on remission and continued to maintenance chemotheraphy for 6 months. We would like to highlight that a small growing cutaneous lesion could be the presenting form of acute lymphoblastic leukemia.

Determination of minimal residual disease in leukaemia patients.

Determination of minimal residual disease in leukaemia patients.

Çocukluk Çağı Akut Lenfoblastik Lösemili Olgularda Yüksek Doz Methotreksat Uygulamasının Oral Glukoz Tolerans Testi Üzerine Etkileri

Effects of High-Dose Methotrexate Therapy on Glucose Metabolism in Childhood Acute Lymphoblastic Leukemia Methotrexate (MTX) has been used in the treatment of childhood acute lymphoblastic leukemia (ALL) for over 40 years. A number of the acute toxicities are common with high dose methotrexate (HDMTX) infusion, including myelosuppression, vomiting, orointestinal mucositis, hepatic and renal toxicities, neurological disturbances. On the other hand, effect of HDMTX therapy on glucose metabolism was not known. Between 2001 and 2002, twenty children with acute lymphoblastic leukemia at the Dr. Sami Ulus Children's Hospital, Department of Pediatric Hematology and Oncology were treated according to the St. Jude ALL XIII protocol were eligible to this study. Dose of MTX (2 gr/m2) was infused over 24 hours. Orally glucose tolerance test was performed at before HDMTX therapy, 1 day and 1 week after the therapy. We found that HDMTX infusion did not significantly effect on orally glucose tolerance test during the first week. Methotreksat (MTX), akut lenfoblastik losemi (ALL) tedavisinde 40 yildan fazla suredir kullanilmaktadir. Yuksek doz MTX (YDMTX) tedavisine bagli myelosupresyon, kusma, mukozit, norolojik bozukluklar, hepatik ve renal toksisite bildirilmistir. Ancak, YDMTX tedavisinin oral glukoz tolerans testi uzerine etkileri bilinmemektedir. Dr. Sami Ulus Cocuk Sagligi ve Hastaliktan Merkezi Pediatrik Hematoloji ve Onkoloji bolumlerinde 2001 - 2002 tarihleri arasi ALL tanisi ile, St. Jude Total XIII ALL protokolunde bulunan ve YDMTX tedavisi almakta olan 20 hasta calismaya alindi. Yuksek DMTX tedavisi 2gr/m2 dozunda, 24 saatlik infizyon seklinde verildi. Tedavi oncesi (TO), tedavi sonrasi 1. gun (TS1G) ve tedavi sonrasi 7. gun (TS7G) oral glukoz tolerans testi (OGTT) uygulandi. Yuksek DMTX tedavisi sonrasindaki 1 hafta suresince glukoz metabolizmasinda belirgin bir degisiklik saptamadik.

The management of high-risk lymphoblastic leukaemia in children.

The management of high-risk lymphoblastic leukaemia in children.