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C Devalck

Publications and source records attributed to C Devalck.

At least 19 recordsLinked to original sources
PubMed2004

Hydroxyurea treatment for sickle cell disease: impact on haematopoietic stem cell transplantation's outcome.

Since 1988, 24 children have undergone haematopoietic stem cell transplantation (HSCT) for severe sickle cell disease (SCD) in our unit, 13 being grafted after having been exposed to hydroxyurea (HU) to control SCD-related complications. Different pre-transplant conditioning regimens were given over time: Bu14/Cy200 in six patients (group 1), Bu16/Cy200/antithymocyte globulin (ATG) in five (group 2) and Bu16/Cy200/ATG with HU prior to HSCT in 13 (group 3). The aim of this study is to compare the outcome after HSCT of these groups of patients, which differ according to pre-transplant drug exposure. Overall, 20 of the 24 transplanted children had stable engraftment and have remained free of SCD-related symptoms after HSCT; 19 of them are currently alive and cured of SCD. In group 1 (HU-, ATG-), we observed one unexplainable late death, one absent engraftment, one late rejection and one mixed stable chimerism. In group 2 (HU-, ATG+), we observed the absence of engraftment in two patients and one early rejection. In group 3 (HU+, ATG+), we observed no cases of either absent engraftment, mixed stable chimerism or late rejection. In our experience, pre-transplant treatment with HU seems to be associated with a lower incidence of rejection/absent engraftment in severe SCD patients. These results need to be confirmed with a larger number of patients.

Anemia, Sickle Cell↗
PubMed2001

Five years of experience with hydroxyurea in children and young adults with sickle cell disease.

The short-term beneficial effect of hydroxyurea (HU) in sickle cell disease (SCD) has been proven by randomized studies in children and adults. The Belgian registry of HU-treated SCD patients was created to evaluate its long-term efficacy and toxicity. The median follow-up of the 93 patients registered is 3.5 years; clinical and laboratory data have been obtained for 82 patients at 1 year, 61 at 2 years, 44 at 3 years, 33 at 4 years, and 22 after 5 years. On HU, the number of hospitalizations and days hospitalized dropped significantly. Analysis of the 22 patients with a minimum of 5 years of follow-up confirm a significant difference in the number of hospitalizations (P =.0002) and days in the hospital (P <.01), throughout the treatment when compared to prior to HU therapy. The probabilities of not experiencing any event or any vaso-occlusive crisis requiring hospitalization during the 5 years of treatment were, respectively, 47% and 55%. On HU, the rate per 100 patient-years of severe events was estimated to be 3.5% for acute chest syndrome, 1.2% for aplastic crisis, 0.4% for splenic sequestration; it was 0% for the 9 patients with a history of stroke or transient ischemic attack followed for an average of 4 years. No important adverse effect occurred. Long-term chronic treatment with HU for patients with SCD appears feasible, effective, and devoid of any major toxicity; in patients with a history of stroke, HU may be a valid alternative to chronic transfusion support. (Blood. 2001;97:3628-3632)

Acute Disease↗
PubMed2000

Hepatic regenerating nodules: a mimic of recurrent cancer in children.

BACKGROUND: Pseudometastatic lesions of the liver may be discovered incidentally in children previously treated for malignant tumour. OBJECTIVE: To describe the radiological pattern of these lesions and to analyse their pathogenesis. MATERIALS AND METHODS: Nine children, 2-12 years' old at the time of diagnosis, are described in this retrospective multicentre report. The primary tumours were: nephroblastoma (n = 2), neuroblastoma (n = 2), Ewing's tumour/PNET (n = 2), non-Hodgkin's lymphoma (n = 1), and osteosarcoma (n = 2), treated by surgery (8/9), chemotherapy (9/9), intensive chemotherapy and bone-marrow transplantation (5/9), and radiotherapy (7/9). Three children suffered veno-occlusive disease (VOD) during treatment. The hepatic assessment was performed by sonography (8/9), Doppler (7/9), multiphase spiral CT (8/9) and MRI (7/9). RESULTS: Lesions were discovered 15 months to 16 years after completing treatment. CT was the most sensitive modality for diagnosis. Lesions were multiple in eight cases, measured 2-50 mm, and appeared hypervascular on the arterial phase of CT and/or MRI in every case. Metastases were excluded on the basis of histological verification (n = 2) and clinical and radiological follow-up. CONCLUSION: Pseudometastatic hypervascular hepatic nodules can appear after treatment of a malignant tumour in children. The hypothesis of benign regenerative lesions secondary to treatment and/or VOD is considered.

Child↗
PubMed2000

Adverse outcome of infants with metastatic neuroblastoma, MYCN amplification and/or bone lesions: results of the French society of pediatric oncology.

To assess the relevance of MYCN amplification and bone lesions in stage 4 neuroblastoma (NB) in infants aged <1 year, 51 infants with stage 4 NB were enrolled. Three groups of patients were defined according to the type of metastases and the resectability of the primary tumour. Group I comprised 21 infants with radiologically detectable bone lesions, Group II 22 patients with an unresectable primary tumour and Group III eight patients with only metaiodobenzylguanidine (MIBG) skeletal uptake. MYCN oncogene content was assayed in 47/51 tumours and found to be amplified in 17 (37%). The 5-year event-free survival (EFS) rate of these 51 infants was 64.1% (+/- 7.1%). In a univariate analysis, bone lesions, MYCN amplification, urinary vanillylmandelic/homovanillic acid ratio and serum ferritin levels adversely influenced outcome. In the multivariate analysis, radiologically detectable bone lesions were the most powerful unfavourable prognostic indicator: the EFS rate was 27.2% for these infants compared to 90% for infants without bone lesions (P<0.0001). Our data emphasize the poor prognosis of infants affected by stage 4 NB with bone lesions, especially when associated with MYCN amplification. Given the poor results in this group whatever the treatment, new therapeutic approaches need to be investigated in the future.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

Discrepant flow cytometric expression and function of P-glycoprotein in neuroblastic tumors.

BACKGROUND: Patients suffering from neuroblastic tumors are currently being classified into prognostic subsets based on different clinical and biologic features. In this study, a triple-color flow cytometric assay and a functional test were applied to neuroblastoma cell lines and patients with a neuroblastic tumor, and the value of P-glycoprotein expression and function as potential prognostic characteristics, was determined. METHODS: Twenty-two single-cell suspensions prepared from tumors, and neuroblasts from four bone marrow samples were analyzed by triple-color flow cytometry. Neuroblasts were identified by NB84-positivity and absence of CD45. P-glycoprotein expression was evaluated using 4E3 and MRK16 antibodies. Eighteen samples were tested with a functional assay, based on accumulation and retention of rhodamine-123 with and without the inhibitor verapamil. Six neuroblastoma cell lines were also evaluated. RESULTS: P-glycoprotein expression was seen in 18 of 26 patient samples and in three of six cell lines. The highest expression levels were found in low stage neuroblastoma and well-differentiated tumors; whereas the highest activities were found in stage 4 neuroblastoma and the lowest in ganglioneuroblastoma and ganglioneuroma patients. In 10 of 17 samples, concordant results were found between the flow cytometric immunological test and immunocytochemistry. CONCLUSIONS: The described flow cytometric technique is a new, alternative approach to detect P-glycoprotein expression and function in neural crest tumors. Based on the expression level and the activity value, patients can be segregated into different phenotypic groups. In particular, those patients with high P-glycoprotein activity might benefit from treatment regimens containing reversal agents.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1999

Defective functional activity and accelerated apoptosis in neutrophils from children with cancer are differentially corrected by granulocyte and granulocyte-macrophage colony stimulating factors in vitro.

We have previously shown that polymorphonuclear leucocytes (PMN) harvested from children with cancer and exposed to chemotherapy exhibit defective bactericidal activities against both Gram-positive and Gram-negative microorganisms as well as accelerated apoptosis. In this study, PMN from children with cancer were evaluated to compare in vitro the corrective effects of the two myeloid colony stimulating factors G-CSF and GM-CSF on these defective pathways. Both G-CSF and GM-CSF were able to increase the defective bactericidal activities against S. aureus and E. coli. However, GM-CSF was consistently superior to G-CSF in correcting PMN microbicidal activity; this correction was incomplete since it did not reach the level observed in normal PMN exposed to GM-CSF. The accelerated apoptosis of PMN was not affected by G-CSF. In contrast, GM-CSF significantly prolonged the survival of the PMN although it did not reach the level of survival observed with normal PMN exposed to GM-CSF. These observations were consistent with other studies indicating that in PMN, microbicidal activities and apoptosis are differentially sensitive to the myeloid growth factors G-CSF and GM-CSF.

Adolescent↗
PubMed1998

CD30(+) anaplastic large-cell lymphoma in children: analysis of 82 patients enrolled in two consecutive studies of the French Society of Pediatric Oncology.

The purpose of this study was (1) to investigate the efficacy of chemotherapy regimens designed by the French Society of Pediatric Oncology for childhood anaplastic large-cell lymphoma (ALCL) and (2) to identify prognostic factors in these children. Eighty-two children with newly diagnosed ALCL were enrolled in two consecutive studies, HM89 and HM91. The diagnosis of ALCL was based on immuno-morphological features and all the cases but 2 were investigated using ALK1 antibody directed to the NPM/ALK protein associated with the 2;5 translocation. Treatment consisted of 2 courses of COPADM (methotrexate, cyclophosphamide, doxorubicin, vincristine, and prednisone) and a maintenance treatment of 5 to 7 months. Seventy-eight patients (95%) achieved a complete remission and 21 relapsed. The probability of survival and event-free survival at 3 years was of 83% (72% to 90%) and 66% (54% to 76%), respectively, with a median follow-up of 49 months. In multivariate analysis, visceral involvement, mediastinal involvement, and lacticodeshydrogenase (LDH) level >/=800 UI/L were shown to be predictive of a higher risk of failure. In conclusion, this type of regimen demonstrated efficacy in childhood ALCL. However, therapeutic results have to be improved for children with adverse prognostic parameters such as visceral or mediastinal involvement or a high LDH level.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

Anemia in children with cancer is associated with decreased erythropoietic activity and not with inadequate erythropoietin production.

A defect in erythropoietin (EPO) production has been advocated as being the main cause of anemia presented at time of diagnosis or during treatment by adults with solid tumors. On the basis of this defect, anemic cancer patients, both adults and children, have been treated with recombinant human EPO (rHuEPO). To further elucidate the pathophysiology of anemia in children with cancer, we measured serum soluble transferrin receptor (sTfR), a quantitative marker of erythropoiesis, and serum EPO at time of diagnosis and during chemotherapy in children suffering from solid tumor or leukemia. We determined serum EPO in 111 children (55 leukemia, 56 solid tumors) at time of diagnosis. In the last 44 patients (23 leukemia and 21 solid tumors), sTfR levels were also measured. Serum EPO together with sTfR levels were also determined in 60 children receiving chemotherapy (29 leukemia, 31 solid tumors). These results were compared with those obtained from appropriate control groups. In all patients, we found a highly significant correlation between the logarithm of EPO (log[EPO]) and the hemoglobin (Hb) level. In all subsets of patients, sTfR levels were inappropriately low for the degree of anemia. Neither leukemic nor solid tumor groups showed a significant inverse relationship between log(sTfR) and the Hb level as would be expected in anemic patients with appropriate marrow response. Thus, in children with cancer, anemia is associated with a decreased total bone marrow erythropoietic activity which, in contrast to what has been reported in anemic cancer adults, is not related to defective EPO production.

Adolescent↗
PubMed1998

Genetic heterogeneity of neuroblastoma studied by comparative genomic hybridization.

Comparative genomic hybridization (CGH) analysis was performed on 36 neuroblastomas of both low and high stage of disease. This study significantly increases the number of neuroblastoma tumors studied by CGH. Analysis of larger series of tumors is particularly important in view of the different clinical subgroups that are recognized for this tumor. The present data and a comparison with all published CGH data on neuroblastoma provide further insights into the genetic heterogeneity of neuroblastoma. Stage 1, 2, and 4S tumors showed predominantly whole chromosome gains and losses. A similar pattern of whole chromosome imbalances, although less frequent, was observed in stage 3 and 4 tumors, in addition to partial chromosome gains and losses. An increase in chromosome 17 or 17q copy number was observed in 81% of tumors. The most frequent losses, either through partial or whole chromosome underrepresentation, were observed for 1p (25%), 3p (25%), 4p (14%), 9p (19%), 11q (28%), and 14q (31%). The presence of 3p, 11q or 14q deletions defines a genetic subset of neuroblastomas and contributes to the further genetic characterization of stage 3 and 4 tumors without MYCN amplification (MNA) and 1p deletion. The present study also provides additional evidence for a possible role of genes at 11q13 in neuroblastoma. In a few cases, 1p deletion or MNA detected by FISH or Southern blotting was not found by CGH, indicating that the use of a second, independent technique for evaluation of these genetic parameters is recommended.

Adolescent↗
PubMed1998

Alveolar soft-part sarcoma: further evidence by FISH for the involvement of chromosome band 17q25.

A cytogenetic study of an alveolar soft-part sarcoma, a rare tumor of probably myogenic origin, demonstrated a t(X;17)(p11;q25) as the sole chromosomal abnormality. Dual- and triple-color fluorescence in situ hybridization, performed on metaphase and interphase cells, confirmed the translocation between chromosomes X and 17 and demonstrated that this translocation resulted in loss of 17q25. Involvement of 17q25 has been described in four previously published cases of alveolar soft-part sarcoma, but without further characterization. Compared to our karyotype, it seems that the derivative chromosome 17 observed in the reported cases could also be the result of a t(X;17) with possible loss of the 17q25 band. If so, a 17q25 deletion and/or chromosome rearrangement between Xp and 17q leading either to a gene fusion or gene disruption could play an important role in the pathogenesis of alveolar soft-part sarcoma.

Child↗
PubMed1997

Comparison between vasoactive intestinal polypeptide and pituitary adenylate cyclase activating polypeptide levels in neuroblastoma tumour tissues.

Vasoactive intestinal polypeptide (VIP) is reported to exert an autocrine control on neuroblastoma cell tumours: VIP is produced by the tumour and stimulates cell differentiation. This study tested the hypothesis that the parent peptide; the pituitary adenylate cyclase activating polypeptide (PACAP) may have a similar role. It was found that PACAP mRNA and PACAP were expressed in 12/12 tumours; it was also observed that PACAP receptor mRNA and functional PACAP receptors were expressed in 12/12 and 5/9 tumours, respectively. VIP mRNA and VIP were detected in 9/12 tumours. VIP receptor mRNA was expressed in 5/12 tumours and functional VIP receptors were never demonstrated. The tumours having the highest VIP levels also had the highest PACAP contents and were associated with a watery diarrhoea syndrome due to activation of intestinal VIP receptors. As PACAP recognizes the PACAP receptors and the VIP receptors with the same high affinity it may contribute to the syndrome and is a likely candidate for an autocrine control of neuroblastoma cell growth and differentiation.

Autocrine Communication↗
PubMed1996

Hydroxyurea for treatment of severe sickle cell anemia: a pediatric clinical trial.

Hydroxyurea (HU) enhances the synthesis of fetal hemoglobin (HbF) and can improve the clinical course of some adult patients with sickle cell anemia (SCA). In a randomized trial, we studied the biologic effects and the clinical benefit of HU in children and young adults with severe SCA. Twenty-five patients (median age, 9 years) were randomized to receive either HU (at the initial dosage of 20 mg/kg/d) or a placebo for 6 months and were then switched to the other arm for the next 6 months. Among the 22 evaluable patients (median age, 8 years), significant increases in HbF and mean corpuscular volume occurred during the HU treatment period. The white blood cell and reticulocytes counts decreased significantly, but these changes were not clinically relevant. Sixteen of 22 patients (73%) experienced a complete disappearance of events requiring hospitalization. The number of days of hospitalization as well as the number of hospitalizations for patients on HU, as compared with those for the patients receiving placebo, were significantly reduced. We conclude that treatment with HU in children and young adults is feasible, well-tolerated, and improves the clinical course of SCA. The long-term effects of HU require further investigation.

Adolescent↗
PubMed1996

Pituitary adenylate cyclase activating peptide and its receptors are expressed in human neuroblastomas.

Vasoactive intestinal peptide (VIP) has been considered as an autocrine growth factor in neuroblastomas. Pituitary adenylate cyclase activating polypeptides (PACAPs) are newly recognized members of the VIP family of neurohormones. As compared to VIP, PACAP has been reported to be biologically more potent and more efficient in tissues expressing selective PACAP receptors rather than common VIP/PACAP receptors. PACAPs and VIP interact with the same affinity and stimulate adenylate cyclase activity with the same efficacy and potency on the VIP receptors, but PACAPs act also on a more selective PACAP receptor that also recognizes VIP but with a 100- to 1,000-fold lower affinity. Thus, depending on the type of receptors expressed at a cell surface, PACAP may be more potent and efficient than VIP. The capacity of 22 surgical specimens of neuroblastomas and of 5 established cell lines to synthesize PACAP and VIP and to synthesize and express PACAP receptors and VIP receptors was studied. Using the reverse transcriptase-polymerase chain (RT-PCR) method with specific primers, we detected the mRNAs coding for PACAP and VIP in 19 and 3 out of 22 samples, respectively. PACAP mRNA was expressed in 3 of the 5 cell lines studied and VIP mRNA in 4. Using the same techniques, PACAP and VIP receptors mRNA were detected in 21, and 13 of the 22 tumor samples and in 5 and 1 of the cell lines studied, respectively. The expression of the PACAP receptor was demonstrated by direct binding studies and/or by the relative potency of PACAPs and VIP to stimulate adenylate cyclase activity in 16 of the 22 tumors and in all the cell lines. In addition, there was no correlation between tumor stage and the expression of mRNA coding for the peptides and the receptors. The present results demonstrated that PACAP could also be a candidate as an autocrine regulator of neuroblastoma which a higher activity than VIP.

Base Sequence↗
PubMed1996

[Leukemia lymphoma T-cell as first manifestation of ataxia-telangiectasia].

BACKGROUND: Variable degrees of T cell deficiency in ataxia-telangiectasia (AT) progressively worsen with time and death from malignant lymphoma is a common terminal event. T-cell lymphoma as the first manifestation of AT has never been reported. CASE REPORT: A 22 month-old girl born to consanguineous parents, was treated for a thoracic T-cell lymphoma and remained in first complete remission, with a follow-up of 4 years. Prior to chemotherapy, cytogenetic studies on blood showed clonal rearrangements including t(7p;14q), T(2p;7q) and inv (7), while karyotype showed 6q- and 1p-mitoses on bone marrow blasts. Hypotonia became evident at 3 years. One year later, the neurological status deteriorated. The patient presented also severe respiratory tract infections. At that time, immunological investigations showed hypo IgG2, very low T4 lymphocytes level, all harbouring the CD45 RO phenotype. Increase in alpha-foetoprotein level, the ocular movements and the study of DNA synthesis after exposure to gamma-rays confirmed the diagnosis of AT. CONCLUSION: In cases of childhood lymphoid neoplasia, AT should be considered whenever parental consanguinity, T-cell proliferation and/or unexpected toxic therapeutic responses are noted.

Ataxia Telangiectasia↗
PubMed1996

Defective polymorphonuclear leukocyte functions in children receiving chemotherapy for cancer are partially restored by recombinant human granulocyte colony-stimulating factor in vitro.

Granulocyte colony-stimulating factor (G-CSF) has important direct and priming effects on different functions of normal mature polymorphonuclear leukocytes (PMNL). Previous study has shown an alteration in respiratory burst and bactericidal activities of PMNL harvested from children with cancer treated with chemotherapy. The present study evaluates the possibility that recombinant human (rh) G-CSF could correct these defective functions in vitro. Free radical formation in defective PMNL was enhanced by rhG-CSF to a level similar to that found in normal PMNL primed by rhG-CSF. The defective bactericidal activity against Escherichia coli and Staphylococcus aureus was also corrected. This bactericidal activity was not different from that observed in normal PMNL primed by rhG-CSF. In conclusion, correction of the altered free radical-formation pathway by rhG-CSF in these cells contributed to the restoration of normal bactericidal activity against both gram-positive and gram-negative microorganisms.

Adolescent↗
PubMed1996

Granulocyte functions in children with cancer are differentially sensitive to the toxic effect of chemotherapy.

To analyze the toxicity associated to chemotherapy upon granulocytes, different functional assays were performed, within days of drug exposure and at time of bone marrow recovery, on polymorphonuclear neutrophils (PMN) from children with cancer. There were no significant postchemotherapy changes in the expression of the different receptors studied nor in the phagocytosis of Staphylococcus aureus 42D. By contrast, a significant decrease was observed in H2O2 production in PMN recently exposed to chemotherapy with both cytofluorometric and chemiluminescence assays. There was also a decrease in the production of O2- and in chemotaxis; finally, the intracellular killing of S. aureus 42D and Escherichia coli was reduced. In patients having recovered from drug-induced bone marrow aplasia, PMN functions were found to be normal except for bactericidal activity which was still defective. The observations indicate that, in patients exposed to chemotherapy, some PMN functions are transiently altered, whereas microorganism cell killing is continuously impaired.

Adolescent↗
PubMed1995

Increased renal parenchymal echogenicity in ifosfamide-induced renal Fanconi syndrome.

Three children who presented with a Fanconi syndrome induced by the chemotherapeutic drug ifosfamide were found to have renal abnormalities on sonogram examinations. Renal echographic changes consisted in hyperechogenicity of the parenchyma with good corticomedullar differentiation. After discontinuation of the chemotherapy, the serum and urine metabolic abnormalities due to proximal tubulopathy were completely or greatly improved. Imaging studies at that time showed a complete resolution of the renal hyperechogenicity. We suggest that in patients exposed to ifosfamide, renal sonogram may be of value to monitor the tubular toxicity of this drug. In these patients, urine and serum monitoring as well as prospective echographic follow-up kidney abnormalities may lead to earlier detection of ifosfamide-induced Fanconi syndrome as well as earlier detection of disease reversibility.

Child↗