Procalcitonin guidance and reduction of antibiotic use in acute respiratory tract infection.

Increasing worldwide development of antimicrobial resistance and the association of resistance development and antibiotic overuse make it necessary to seek strategies for safely reducing antibiotic use and selection pressure. In a first step, in a non-interventional study, the antibiotic prescription rates, initial procalcitonin (PCT) levels and outcome of 702 patients presenting with acute respiratory infection at 45 primary care physicians were observed. The second part was a randomised controlled non-inferiority trial comparing standard care with PCT-guided antimicrobial treatment in 550 patients in the same setting. Antibiotics were recommended at a PCT threshold of 0.25 ng·mL(-1). Clinical overruling was permitted. The primary end-point for non-inferiority was number of days with significant health impairment after 14 days. Antibiotics were prescribed in 30.3% of enrolled patients in the non-interventional study. In the interventional study, 36.7% of patients in the control group received antibiotics as compared to 21.5% in the PCT-guided group (41.6% reduction). In the modified intention-to-treat analysis, the numbers of days with significant health impairment were similar (mean 9.04 versus 9.00 for PCT-guided and control group, respectively; difference 0.04; 95% confidence interval -0.73-0.81). This was also true after adjusting for the most important confounders. In the PCT group, advice was overruled in 36 cases. There was no significant difference in primary end-point when comparing the PCT group treated as advised, the overruled PCT group and the control group (9.008 versus 9.250 versus 9.000 days; p = 0.9605). A simple one-point PCT measurement for guiding decisions on antibiotic treatment is non-inferior to standard treatment in terms of safety, and effectively reduced the antibiotic treatment rate by 41.6%.

Experimental demonstration of a synthetic aperture compression scheme for multi-Petawatt high-energy lasers.

We present the experimental demonstration of a subaperture compression scheme achieved in the PETAL (PETawatt Aquitaine Laser) facility. We evidence that by dividing the beam into small subapertures fitting the available grating size, the sub-beam can be individually compressed below 1 ps, synchronized below 50 fs and then coherently added thanks to a segmented mirror.

Risk factors for hepatic veno-occlusive disease: a retrospective unicentric study in 116 children autografted after a high-dose BU-thiotepa regimen.

At our Institute, during the last decade, the incidence of hepatic veno-occlusive disease (HVOD) appears to be on the increase among pediatric patients treated with BU-thiotepa (BU-TTP)-conditioning regimen. We thus performed a retrospective analysis to identify the risk factors for HVOD, which could explain such a change. In total, 116 patients treated at Institut Gustave Roussy, between May 1998 and December 2005 were eligible for this study having received BU-TTP as their first high-dose chemotherapy regimen, followed by autologous hematopoietic SCT (AHSCT). According to McDonald's clinical criteria, HVOD was diagnosed in 31% of these children. Demographic, clinical, biological and therapeutic parameters were evaluated in uni- and multivariate analyses that showed a significant correlation between previous carboplatin therapy and risk of developing post transplant HVOD (P=0.028). Comparable results were found for etoposide (P=0.048). In addition, a correlation between HVOD and risk of post transplant death was linked to its association with other types of organ failure (P=0.029). This study demonstrates that previous VPCARBO administration in conventional chemotherapy significantly increases the risk of HVOD among brain tumor patients later consolidated with BU-TTP followed by AHSCT.

siRNA-mediated AML1/MTG8 depletion affects differentiation and proliferation-associated gene expression in t(8;21)-positive cell lines and primary AML blasts.

The chromosomal translocation t(8;21) is associated with 10-15% of all cases of acute myeloid leukaemia (AML). The resultant fusion protein AML1/MTG8 interferes with haematopoietic gene expression and is an important regulator of leukaemogenesis. We studied the effects of small interfering RNA (siRNA)-mediated AML1/MTG8 depletion on global gene expression in t(8;21)-positive leukaemic cell lines and in primary AML blasts using cDNA arrays, oligonucleotide arrays and real-time reverse transcription-polymerase chain reaction (RT-PCR). Suppression of AML1/MTG8 results in the increased expression of genes associated with myeloid differentiation, such as AZU1, BPI, CTSG, LYZ and RNASE2 as well as of antiproliferative genes such as IGFBP7, MS4A3 and SLA both in blasts and in cell lines. Furthermore, expression levels of several genes affiliated with drug resistance or indicative of poor prognosis AML (BAALC, CD34, PRG2, TSPAN7) are affected by AML1/MTG8 depletion. In conclusion, siRNA-mediated suppression of AML1/MTG8 cause very similar changes in gene expression pattern in t(8;21)-positive cell lines and in primary AML blasts. Furthermore, the results suggest that the specific targeting of AML1/MTG8 function may be a promising approach for complementing existing treatment strategies.

Elevated plasma ferritin and busulfan pharmacodynamics during high-dose chemotherapy regimens in children with malignant solid tumors.

Hepatic veno-occlusive disease (HVOD) is a frequent complication during hematopoietic stem-cell transplantation (HSCT). A strong relationship has been demonstrated between busulfan exposure and HVOD for busulfan-cyclophosphamide and allogeneic HSCT in adults. Busulfan disposition after the first intake was studied in 77 children treated for solid malignancies with high-dose busulfan-containing regimens and autologous HSCT. Busulfan was combined with cyclophosphamide and melphalan (n=30), melphalan (n=27), and thiotepa (n=20). No relationship was observed between busulfan exposure and HVOD. In contrast, plasma ferritin at baseline was higher in patients with HVOD (750 ng/ml (20-3,110)) compared with those without HVOD (189 ng/ml (8-3,967), P=0.012). Multivariate analysis showed that a ferritin level exceeding 300 ng/ml was the only risk factor for HVOD with an odds ratio of 4.0 (confidence interval 95% (1.5-11.2), P=0.0071). A high ferritin level at baseline was explained by the diagnosis of neuroblastoma, related treatments and transfusions.

Haematopoietic stem cell transplantation trends in children over the last three decades: a survey by the paediatric diseases working party of the European Group for Blood and Marrow Transplantation.

This paper describes the trends in haematopoietic stem cell transplantation (HSCT) activity for children in Europe over the last three decades. We analysed 31,713 consecutive paediatric HSCTs reported by the European Group for Blood and Marrow Transplantation (EBMT) centres between 1970 and 2002. Data were taken from the EBMT registry and were compared according to period and centre category (paediatric or combined). Since 1996, there has been a significant increase in the number of HSCTs performed exclusively by paediatric centres, as well as in the number of alternative donor HSCTs, and in the use of peripheral blood stem cells (P<0.0001). The number of allogeneic HSCTs (allo-HSCTs) for acute lymphoblastic leukaemia, acute myeloblastic leukaemia and chronic myeloid leukaemia remained stable, whereas it increased for myelodysplastic syndromes and lymphomas, and decreased significantly for non-malignant diseases (P<0.0001). Multivariate analysis showed that younger age, human leukocyte antigen genoidentical donors, HSCT performed after 1996 and transplant centres performing more than 10 allo-HSCT/year were all associated with decreased transplant-related mortality (TRM) (P<0.0001). The number of autologus HSCTs (auto-HSCTs) for acute leukaemia decreased significantly, whereas it increased for solid tumours (P<0.0001). Multivariate analysis showed that both auto-HSCT performed before 1996 and paediatric solid tumours (P<0.0001) had higher TRM. Indications for paediatric HSCT have changed considerably during the last seven years. These changes provide tools for decision making in health-care planning and counselling.

Inhibition of retinoic acid receptor signaling by Ski in acute myeloid leukemia.

Acute myeloid leukemia (AML) is a heterogeneous disease with multiple different cytogenetic and molecular aberrations contributing to leukemic transformation. We compared gene expression profiles of 4608 genes using cDNA-arrays from 20 AML patients (nine with -7/del7q and 11 with normal karyotype) with 23 CD34+ preparations from healthy bone marrow donors. SKI, a nuclear oncogene, was highly up regulated. In a second set of 183 AML patients analyzed with real-time PCR, the highest expression level of SKI in AML with -7/del7q could be confirmed. As previously described, Ski associates with the retinoic acid receptor (RAR) complex and can repress transcription. We wanted to investigate the interference of Ski with RARalpha signaling in AML. Ski was co-immunoprecipitated and colocalized with RARalpha. We also found that overexpression of wild-type Ski inhibited the prodifferentiating effects of retinoic acid in U937 leukemia cells. Mutant Ski, lacking the N-CoR binding, was no more capable of repressing RARalpha signaling. The inhibition by wild-type Ski could partially be reverted by the histone deacetylase blocking agent valproic acid. In conclusion, Ski seems to be involved in the blocking of differentiation in AML via inhibition of RARalpha signaling.

[A multidisciplinary consultation for children with brain tumors]. / Une consultation multidisciplinaire pour les enfants traités pour une tumeur cérébrale.

UNLABELLED: School achievement of children with brain tumors is hampered by progressive neurologic and cognitive sequelae. To help the children and their family, we have created in 1997 a multidisciplinary consultation together with Necker's hospital. MATERIAL AND METHODS: The study describes the organization of the consultation and analyses the files of 69 children seen between September 2001 and June 2002. RESULTS AND CONCLUSION: The authors conclude that this consultation is an irreplaceable mean to coordinate the complex rehabilitation process of a child treated for a brain tumor.

Correlation of MDR1 gene expression with chemotherapy in neuroblastoma.

Forty-one neuroblastoma tumor specimens have been analyzed by Northern and slot blot hybridization techniques with human MDR1 gene probes. Only one of 15 (6%) tumors from patients who had not received chemotherapy exhibited high levels of MDR1 transcripts, while 11 of 26 (42%) treated tumors showed high levels of MDR1 expression (Fisher exact test: P = .03). The results indicate that the level of MDR1 mRNA expression is associated with previous chemotherapy, including drugs that select the multidrug resistance phenotype in vitro regardless of neuroblastoma tissue origin or N-myc content in the genome. For the 26 treated neuroblastomas, the number of nonresponsive tumors was found to be significantly higher among those with high levels of MDR1 mRNA.

Modified chemotherapy with carmustine, cytarabine, cyclophosphamide, and 6-thioguanine (BACT) and autologous bone marrow transplantation in 24 poor-risk patients with acute lymphoblastic leukemia.

Twenty-four poor-risk patients with acute lymphoblastic leukemia received a modified regimen of carmustine, cytarabine, cyclophosphamide, and 6-thioguanine (BACT) followed by autologous bone marrow transplantation (ABMT). Nineteen patients were in second or subsequent complete remission (CR) when treated with this regimen; 3 died early, 2 died of pneumonia in CR, 11 relapsed within 3 months (median), and 3 remain in CR with no maintenance therapy 14-24 months after ABMT. Of the 5 patients with measurable disease who were treated, 3 had CR and 1 remains in CR without maintenance therapy more than 28 months after ABMT. The toxicity of this regimen was acceptable, but late pulmonary toxic effects remain a major concern. These results are poor in terms of efficacy, and new effective methods of eradicating acute lymphoblastic leukemia in patients with poor prognosis should be investigated.

[Targeted therapies in pediatric oncology: a new therapeutic approach?]. / Thérapies ciblées en oncologie pédiatrique: nouvelle approche thérapeutique.

A multidisciplinary therapeutic approach has led to significant increase in survival of children with cancer, however often with a high rate of severe sequela. Better understanding in tumor cell biology and transformation process allowed to describe active tyrosine kinases (mainly growth factor receptors) as a new target for cancer treatment. This review presents 2 approaches to target receptor tyrosine kinase activity: on one hand, antibodies that target the extracellular domain, the natural ligand binding site, and on the other hand, small inhibiting molecules, such as imatinib, targeted against the activated intracellular receptor tyrosine kinase. We focus on their clinical development and current application in the treatment of childhood cancer. Targeted therapies are in full rise and new perspectives are explored, such as their association to other treatment modalities and the targeting of microenvironment. This new therapeutic approach necessitates well designed clinical trials that include relevant biomarkers to evaluate its real therapeutic potential.

[Malignant solid tumors in neonates: a study of 71 cases]. / Tumeurs solides malignes néonatales: à propos de 71 cas.

UNLABELLED: Malignant neonatal tumors are rare and comprise 2% of childhood malignancies. Clinical features, histologic types, prognosis were very different from those seen in older children, facing oncologists with diagnostic, therapeutic and ethical problems. PATIENTS AND METHODS: In a retrospective study from January 1987 to January 2004, we reviewed the management of neonates treated at the Institute Gustave Roussy for a malignant solid tumor for whom symptoms started in the first month of life. RESULTS: Seventy-one neonates were treated, comprising 1,2% of the overall patients treated during the same period of time. Of these 71 patients, 42 (59%) presented with neuroblastomas, 12 (17%) with mesenchymal tumors, 6(8%) with cerebral tumors and 11 with various other types of tumors. Fifty-nine patients underwent surgical resection. Thirty-eight neonates received chemotherapy, administered at a 30 to 50% reduced dose. Hematologic toxicities and infections were the main therapeutic complications. Very small doses of radiotherapy were used in only 5 children. There has been no therapy-related mortality. Twenty-two of the 57 survivors have sequelae, especially patients with intraspinal neuroblastoma. The 5 year overall survival was 79%. CONCLUSIONS: Neonatal malignant solid tumors, except for cerebral tumors, have a good prognosis. The young age of patients resulted in problems of treatment tolerance. The therapeutic regimen should take into account the risk of acute iatrogenic toxicity and long term sequelae. Surgery remains the treatment of choice but chemotherapy, with dose reduction, managed by expert teams, is essential and safer in a lot of case.

[Ifosfamide induced encephalopathy: 15 observations]. / Encéphalopathie induite par l'ifosfamide: 15 observations.

INTRODUCTION: Ifosfamide is an alkylating agent used in the treatment of germ-cell tumors, sarcomas and lymphomas. One of its main side effects is the encephalopathy of which the incidence may reach 30% in the literature, in adults and children just as well. OBJECTIVES: Based on both our experience and a review of the literature, we propose some recommendations for the management of this complication. PATIENTS AND METHODS: We report 15 encephalopathy cases in non-brain tumor patients, which occurred between January 1987 and March 2002 in children from 2 to 17 years old, treated for solid tumors at the Institut Gustave Roussy. Ifosfamide was administered at a posology between 5.4 and 15 g/m(2)/course, associated with other antimitotics such as actinomycin D, etoposide or vincristine. RESULTS: Six patients experienced a grade III neurological toxicity according to the NCI classification, which developed as excess drowsiness lasting up to 36 hours. Six other patients developed grade IV neurotoxicity, including two comas resolving within 4 days and four short generalized convulsions. Three other children experienced grade II drowsiness. Brain MRIs were normal and EEG showed an aspecific encephalopathy tracing. This early central neurotoxicity appeared right from the first administration, and occurred immediately after the first injection or during the second or third day of treatment. It was most often reversible, usually 3 to 5 days after the last ifosfamide administration. Five patients were administered a treatment with Methylene Blue with a demonstrable efficacy in only one case. No death or neurological sequelae have been noted. Ifosfamide has been renewed after the neurological accident in 7 of those patients. Only 1 of those 7 patients developed grade IV neurotoxicity during the next course of treatment. In 2 of those 7 children, Methylene Blue was used in a prophylactic way. No neurological disorders have been noted during the next courses of treatment. DISCUSSION: In the literature, the following are described as risk factors for ifosfamide encephalopathy: advanced pelvic disease, previous cisplatyl treatment and renal failure. We have not found any of these predisposing factors in our series, but three of the fifteen patients had severe neurotoxicity associated with Vincristin during previous treatments. CONCLUSION: Facing a clinical diagnosis of ifosfamide encephalopathy, it is recommended to discontinue administration of ifosfamide and inject by intravenous route 50 mg Methylene Blue every 4 hours until the symptomatology recedes. The re-challenge of Ifosfamide is not contra-indicated and should be performed under prophylactic treatment with Methylene Blue by intravenous route at the dose of 50 mg every 6 hours.

Splenic granulopoiesis in mice following administration of cyclophosphamide.

The adult mouse spleen retains granulocytic progenitor cells that are capable of proliferation and maturation. In mice given cyclophosphamide, spleen weight and cell content increased. In vitro granulocyte progenitor cells increased more than 300-fold in the spleen and remained elevated 14 days following cyclophosphamide. Proliferative and nonproliferative granulocytes were increased above controls until Days 21 and 28, respectively. In splenectomized mice, blood neutrophil recovery was delayed when compared to nonsplenectomized mice following cyclophosphamide. Although marrow cell number was similar in both groups, maximum marrow granulocyte progenitor cells were 2-fold greater in nonsplenectomized animals. These studies demonstrate that the murine spleen becomes a markedly granulopoietic organ and is a major contributor to recovery of granulocytes following cyclophosphamide. Splenic granulopoiesis should be taken into account in studies which measure toxicity of various agents in murine hematopoiesis.

T-cell receptor repertoire in neuroblastoma patients.

Spontaneous regression of widespread lesions is a characteristic feature of neuroblastoma. One may postulate that the immune response contributes to these clinical regressions. Accordingly, we studied the T-cell receptor (TCR) repertoire of tumor-infiltrating lymphocytes in eight neuroblastoma tumors. The expression of 29 V alpha and 24 V beta gene segment subfamily specificities was analyzed by PCR and compared by computerized densitometry of Southern blots to values obtained in the blood. Overall, the TCR repertoire of these eight patients was diverse, with virtually all V alpha and V beta specificities expressed. Nonetheless, four of these patients showed V beta 2 gene segment subfamily overexpression in the tumor corresponding to local expansion of polyclonal T-cell subpopulations. In one patient, this expansion could be due to local secretion of superantigenic activity, as suggested by the specific stimulation of murine T cells expressing a human V beta 2 chain by supernatant of the corresponding neuroblastoma cell line. In addition, high-resolution analysis of the TCR beta transcript complementarity-determining region 3 sizes identified three patients (of six studied) with marked clonal T-cell expansion in the tumor not seen in the blood. The specific expression of several dominant clono-types in the tumor may be related to the recognition of neuroblastoma-specific antigens in these patients. Together, these results on the TCR repertoire expressed in vivo may lead to the characterization of putative immune response mechanisms (i.e., antigen- or superantigen-driven stimulation) which participate in tumor regression.

Chronopharmacology of high-dose busulfan in children.

In bone marrow transplantation, high-dose busulfan is given p.o., usually every 6 h over 4 consecutive days. Since this repeated administration might alter busulfan disposition, fluctuations in busulfan plasma levels were studied over the 4-day treatment period in 21 children (median age, 5 years) with malignant solid tumors. In addition, urinary excretion of unchanged busulfan was measured every 6 h in 4 patients. Busulfan (37.5 mg/m2 for 16 doses) was given on an empty stomach at 12 p.m., 6 p.m., midnight, and 6 a.m. for 4 consecutive days, starting at 12 p.m. Trough plasma levels, i.e., concentration 6 h after each dose and just before the next one, and urinary excretion of busulfan were measured using a gas chromatography-mass spectrometry assay. Busulfan trough plasma levels exhibited a significant circadian rhythm with a higher mean level at 6 a.m. compared to that at 12 p.m., 6 p.m., and midnight. This rhythm was characterized by a double amplitude (mean +/- SD) of 42 +/- 14% and an acrophase (maximum) occurring at 5:48 a.m. +/- 115 min. In addition, once the steady state was reached, no decreasing trend was observed in any patient. Busulfan renal clearance proved to be low since only 5.4 +/- 1.2% of the given dose were excreted unchanged in urine. In the 4 patients studied, busulfan urinary excretion exhibited a significant circadian rhythm which was apparently linked to the physiological circadian rhythm in urinary output. Ten of 20 evaluable patients developed hepatic venoocclusive disease (HVOD). A significant circadian rhythm in the plasma level was found in both HVOD and non-HVOD patients with no difference between the two groups with regard to the 24-h mean, amplitude, or acrophase. Thus, the circadian changes in busulfan trough plasma levels observed at the steady state were not related to the occurrence of HVOD in these children with solid tumors. Moreover, since this rhythm was stable from day 2 to day 4, it should not compromise dose adjustment.

Combined analysis of DNA ploidy index and N-myc genomic content in neuroblastoma.

The aim of the study was to assess, in a group of nonselected patients with neuroblastoma, the prognostic value of both N-myc gene amplification and DNA ploidy index, taking into account potential confounding factors such as age and stage. Of 59 patients studied, 23 were younger than 1 year at diagnosis, 31 presented with stage IV, 10 with stage III, 5 with stage II, 8 with stage I, and 4 with stage IV-S. N-myc genomic content was analyzed by Southern blot hybridization technique and N-myc amplification (greater than or equal to 3 copies/haploid genome) was present in 6 stage IV, 2 stage III, and 1 stage IV-S. The DNA ploidy index was analyzed by flow cytometry. Of the 59 neuroblastomas, 26 were diploid (DNA index, 1) and 33 were aneuploid (DNA index, greater than 1). The majority of the aneuploid tumors (28 of 33) were near-triploid with DNA indexes between 1.25 and 1.68, 4 were near-diploid (DNA index up to 1.18), and 1 was hypotetraploid (DNA index, 1.85). The proportion of near-triploid tumors was significantly greater among patients under 1 year of age and among patients presenting with stages I, II, and IV-S. Interestingly, 0 of 28 near-triploid neuroblastomas exhibited N-myc gene amplification, compared to 9 of 31 in the group of diploid, near-diploid, and hypotetraploid tumors (Fisher's exact test, P less than 0.001). Four factors were significantly related to a high risk of relapse in univariate analysis, i.e., age, stage, DNA index, and N-myc amplification. In multivariate analysis, only N-myc amplification and the DNA index remained significantly associated with a high risk of relapse. The 2-year disease-free survival rate was 94% (95% confidence interval, 77-98%) for patients with near-triploid neuroblastoma, compared to 45 and 11% (95% confidence interval, 32-70 and 4-23%) for patients with diploid or near-diploid tumors, without and with N-myc amplification, respectively. We concluded that the combination of N-myc and DNA index should be included in routine management of neuroblastoma.

Dose-dependent neurotoxicity of high-dose busulfan in children: a clinical and pharmacological study.

Busulfan is known to be neurotoxic in animals and humans, but its acute neurotoxicity remains poorly characterized in children. We report here a retrospective study of 123 children (median age, 6.5 years) receiving high-dose busulfan in combined chemotherapy before bone marrow transplantation for malignant solid tumors, brain tumors excluded. Busulfan was given p.o., every 6 hours for 16 doses over 4 days. Two total doses were consecutively used: 16 mg/kg, then 600 mg/m2. The dose calculation on the basis of body surface area results in higher doses in young children than in older patients (16 to 28 mg/kg). Ninety-six patients were not given anticonvulsive prophylaxis; 7 (7.5%) developed seizures during the 4 days of the busulfan course or within 24 h after the last dosing. When the total busulfan dose was taken into account, there was a significant difference in terms of neurotoxicity incidence among patients under 16 mg/kg (1 of 57, 1.7%) and patients under 600 mg/m2 (6 of 39, 15.4%) (P less than 0.02). Twenty-seven patients were given a 600-mg/m2 busulfan total dose with continuous i.v. infusion of clonazepam; none had any neurological symptoms. Busulfan levels were measured by a gas chromatographic-mass spectrometry assay in the plasma and cerebrospinal fluid of 9 children without central nervous system disease under 600 mg/m2 busulfan with clonazepam:busulfan cerebrospinal fluid:plasma ratio was 1.39. This was significantly different (P less than 0.02) from the cerebrospinal fluid:plasma ratio previously defined in children receiving a 16-mg/kg total dose of busulfan. This study shows that busulfan neurotoxicity is dose-dependent in children and efficiently prevented by clonazepam. A busulfan dose calculated on the basis of body surface area, resulting in higher doses in young children, was followed by increased neurotoxicity, close to neurotoxicity incidence observed in adults. Since plasma pharmacokinetic studies showed a faster busulfan clearance in children than in adults, this new dose may approximate more closely the adult systemic exposure obtained after the usual 16-mg/kg total dose, with potential inferences in terms of anticancer or myeloablative effects. The busulfan dose in children and infants undergoing bone marrow transplantation should be reconsidered on the basis of pharmacokinetic studies.

A lack of neuroblastoma in Down syndrome: a study from 11 European countries.

An epidemiological investigation in 11 European countries comprising a total childhood population of 54.1 million children and using 8 separate data sources was conducted to evaluate the occurrence of neuroblastoma in Down syndrome (DS). No cases of DS were detected among 6724 infants and children with neuroblastoma, although more than five were expected. This highly significant result (P = 0.0045 according to the Poisson test) is consistent with data in the literature, which contains only two poorly detailed cases in epidemiological studies and one ganglioneuroma in a DS mosaic patient. Like other tumors, such as leukemias, testicular germ cell tumors and lymphomas are in excess in DS patients; the lack of neuroblastomas does not reflect a general decreased incidence of cancer but rather a specific underrepresentation of this precise tumor. S-100 b protein, the gene for which maps to the long arm of chromosome 21, (a) is overproduced in DS patients, (b) produces growth inhibition and differentiation of neural cells in vitro, (c) is abundant in good-prognosis neuroblastomas, and (d) has been shown to induce growth inhibition and differentiation and cell death in several human and murine neuroblastoma cell lines and could be responsible for this variation. Additional epidemiological and experimental studies are warranted to confirm our interpretation of these data.

Busulfan-melphalan in high-risk neuroblastoma: the 30-year experience of a single institution.

High-dose chemotherapy (HDC) was investigated in high-risk neuroblastoma (HR-NBL) to reduce the risk of relapse. We report the results of the 30-year experience of a cohort of patients with HR-NBL treated with high-dose (HD) busulfan (Bu)-containing regimens. From 1980 to 2009, 215 patients aged >1 year with stage 4 NBL were treated with HD Bu-containing regimens at Gustave Roussy. These data were prospectively recorded in the Pediatric Transplantation Database. The median age at diagnosis was 40 months (12-218 months). All patients had a stage 4 neuroblastoma. NMYC amplification was displayed in 24% of the tumors. The hematopoietic support consisted of bone marrow or PBSCs in 46% and 49% of patients, respectively. The 5-year event-free survival and overall survival rates of the whole cohort were 35.1% and 40%, respectively. Age at diagnosis, bone marrow involvement and tumor response after induction chemotherapy were significant prognostic factors. Toxicity was manageable and decreased over time, owing to both PBSC administration and better supportive care. Based on this experience, HD Bu-melphalan (Mel) has been implemented in Europe and compared with Carboplatin-Etoposide-Mel in the European SIOP Neuroblastoma (SIOPEN)/HR-NBL randomized protocol. It has now become the standard HDC in the SIOPEN HR strategy.