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Dominique Valteau-Couanet

Publications and source records attributed to Dominique Valteau-Couanet.

17 recordsLinked to original sources
PubMed2007

Feasibility of ovarian tissue cryopreservation for prepubertal females with cancer.

BACKGROUND: Loss of fertility is one of the long-term adverse effects of high-dose chemotherapy or total body irradiation for cancer, even in children. Ovarian tissue cryopreservation (OTC) may make it possible for survivors of childhood cancer to have children. We evaluated the feasibility of this technique for prepubertal girls. METHODS: Between September 2000 and February 2005, 49 prepubertal girls were referred to the Reproductive Biology Unit for OTC before sterilizing treatment. RESULTS: One ovary each was collected from 47 patients, by laparoscopy in 24 patients and laporotomy in the others. In 16 cases, the ovary was harvested during laparotomy to resect a residual abdominal tumor. No complications occurred after operations. Ovarian tissue was frozen by a slow-cooling protocol, using DMSO and sucrose as cryoprotectants. An mean of 17.6 +/- 6.5 ovarian tissue fragments was cryopreserved per patient. Follicle concentration was evaluated histologically for 46 patients and a strong correlation was found between age and follicular density. None of the cases had visible ovarian tumor components. Ovarian cryopreservation was not carried out for two patients. CONCLUSION: The cryopreservation of ovarian tissue could be systematically offered even to prepubertal girls at risk of sterility due to gonadotoxic treatment.

Adolescent↗
PubMed2006

Phase II study of temozolomide in relapsed or refractory high-risk neuroblastoma: a joint Société Française des Cancers de l'Enfant and United Kingdom Children Cancer Study Group-New Agents Group Study.

PURPOSE: To determine the response rate (RR) of neuroblastoma (NB) in children to temozolomide (TMZ), and evaluate the duration of response and tolerance of the drug in this patient population. PATIENTS AND METHODS: A multicenter, phase II evaluation of an oral, daily schedule of TMZ (200 mg/m2/d x 5 days every 28 days) was undertaken in children with refractory or relapsed high-risk NB (metastatic or localized with Myc-N amplification). Response assessment was based on imaging with two-dimentional measurement of disease and meta-iodobenzylguanidine (MIBG) score. Activity was defined by a reduction in lesion size or isotope uptake at anytime. Methodology included a two-step design using Fleming's method with a first step of 15 patients and a second of 10 additional patients if two to four responses had been observed in the first cohort. All data was centrally reviewed by a panel. RESULTS: Twenty-five assessable patients were recruited over a 14-month period in 14 centers and received 94 cycles of chemotherapy. Twenty-three patients had metastatic NB either refractory (n = 9) or in relapse (n = 14). Grade 3 or 4 thrombocytopenia was the most frequent toxicity (16% of cycles). Myelosuppression resulted in treatment delays and dose reductions (24% and 21% of cycles, respectively). Response (complete response, very good partial response, or partial response) was observed in five patients (RR = 20% +/- 8%) with a median duration of 6 months and an objective or mixed response in five additional patients. CONCLUSION: Temozolomide shows activity in heavily pretreated patients with NB, and deserves further evaluation in combination with another drug.

Adolescent↗
PubMed2006

Prognostic factors for death due to invasive aspergillosis after hematopoietic stem cell transplantation: a 1-year retrospective study of consecutive patients at French transplantation centers.

BACKGROUND: Invasive aspergillosis (IA) is a major cause of death after hematopoietic stem cell transplantation (HSCT). The goal of this retrospective and consecutive survey was to assess prognostic factors of death due to IA after HSCT at the time of diagnosis of IA. METHODS: All 64 health care centers affiliated with the Société Française de Greffe de Moelle et de Thérapie Cellulaire were contacted to participate in this study of all proven or probable cases of IA that occurred among HSCT recipients in 2002. Data for 51 cases (41 involving allogeneic HSCT and 10 involving autologous HSCT) were collected from patient records and included diagnostic and therapeutic features of IA, outcome, presence of hematological disease, and transplantation data. Cox models were applied to risk factors for death attributed to IA that were initially identified using the usual tests. RESULTS: The proportion of deaths attributed to IA within 4 months after diagnosis was 0.62 (95% confidence interval, 0.47-0.76). Seven factors assessed at diagnosis were determined to be strongly related to death due to IA: age of 12-35 years, dissemination of IA, presence of a pleural effusion, monocyte count of <120 cells/mm3, prolonged administration of steroids within the previous 2 months, receipt of a dose > or =2 mg/kg at the time of diagnosis, and uncontrolled graft-versus-host disease.Conclusions. Our study explored potential risk factors for death due to IA among HSCT recipients as a reference for investigation in larger future studies. These factors should help to identify HSCT recipients who would benefit from more-aggressive antifungal therapies.

Adolescent↗
PubMed2006

Impact of TBI on late effects in children treated by megatherapy for Stage IV neuroblastoma. A study of the French Society of Pediatric oncology.

PURPOSE: To determine the contribution of total body irradiation (TBI) to late sequelae in children treated with high-dose chemotherapy and autologous bone marrow transplantation for Stage IV neuroblastoma. PATIENTS AND METHODS: We compared two populations that were similar with regard to age, stage, pre-autologous bone marrow transplantation chemotherapy (CT) regimen, period of treatment, and follow-up (12 years). The TBI group (n = 32) received TBI as part of the megatherapy procedure (1982-1993), whereas the CT group (n = 30) received conditioning without TBI (1985-1992). Analysis 12 years later focused on growth, weight and corpulence (body mass index) delay; hormonal deficiencies; liver, kidney, heart, ear, eye, and dental sequelae; school performance; and the incidence of secondary tumors. RESULTS: Impact of TBI was most marked in relation to growth and weight delay, although the mean delay was not severe, probably because of treatment with growth hormones. Other consequences of TBI were thyroid insufficiency, cataracts, and a high incidence of secondary tumors. Hearing loss and dental agenesis were more prominent in the group treated with CT alone. No differences were observed in school performance. CONCLUSION: The most frequent side effects of TBI were cataracts, thyroid insufficiency, and growth delay, but more worrying is the risk of secondary tumors. Because of the young mean age of patients and the toxicity of TBI regimens without any survival advantage, regimens without TBI are preferable in the management of Stage IV neuroblastoma.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2005

Results of induction chemotherapy in children older than 1 year with a stage 4 neuroblastoma treated with the NB 97 French Society of Pediatric Oncology (SFOP) protocol.

PURPOSE: To test the metastatic response rate in stage 4 neuroblastoma, using dose-intensive induction chemotherapy in a multi-institutional setting. PATIENTS AND METHODS: From 1998 to 1999, 47 consecutive children were treated according to N7 protocol. Children received cyclophosphamide 140 mg/kg, doxorubicin 75 mg/m(2), and vincristine 0.066 mg/kg (CAV) in cycles 1, 2, 4, and 6, and cisplatinum 200 mg/m(2) and etoposide 600 mg/m(2) (P/VP) in cycles 3, 5, and 7. The International Neuroblastoma Staging system was used with an emphasis on skeletal evaluation by 123-iodine-metaiodobenzylguanidine (MIBG) scintigraphy. A phase II study evaluating the metastasis complete response rate after induction chemotherapy was conducted in patients who had positive metastatic sites on MIBG scans at diagnosis. RESULTS: Forty-six patients were assessable for toxicity. Hematologic toxicity was the main toxicity observed. Neutropenia was more frequent after CAV than after P/VP (P < .001). A higher rate of thrombocytopenia was observed after P/VP (P = .03). Forty patients with positive MIBG were assessable for metastatic response, and complete regression of metastases was achieved in 17 patients (ie, 43%; 95% CI, 27% to 59%). Of all 47 patients, 21 achieved complete metastatic response. CONCLUSION: The N7 induction chemotherapy protocol was feasible in a multicentric setting. The observed metastasis complete response rate was similar to that obtained in our previous studies and significantly lower than that published in a previous series using the same regimen. In our hands, escalating doses of cyclophosphamide and prolonging conventional chemotherapy with the same drugs failed to improve the metastasis complete response rate.

3-Iodobenzylguanidine↗
PubMed2005

Preoperative chemotherapy in children with high-risk medulloblastomas: a feasibility study.

OBJECT: The authors set out to evaluate the feasibility and effectiveness of preoperative chemotherapy in treating high-risk medulloblastomas. METHODS: Between 1997 and 2000, 21 children with high-risk medulloblastomas (M > or = 2 and/or T3b/T4 according to the Chang classification) were treated consecutively in a pilot study. The protocol began with treatment of the hydrocephalus and confirmation of the diagnosis. Tumor surgery was performed either after conventional chemotherapy (eight patients) or after subsequent high-dose chemotherapy (HDCT; 11 patients). Two children with early leptomeningeal progression died before surgery. Craniospinal irradiation was applied to children older than 5 years of age, whereas younger children received local irradiation only. Hydrocephalus was present in 17 children and was treated with ventriculocisternostomy in 13 and shunt insertion in four. A biopsy procedure was performed with a stereotactic frame in 10 children, an open surgery was performed in four, an endoscope was used during the ventriculocisternostomy in three, and the diagnosis was made based on cerebrospinal fluid cytological analysis in two. The response rate to the first two courses of chemotherapy was 71% for the tumor and 59% for the metastases. The pathological analysis of the residue after chemotherapy showed true medulloblastomas in seven cases, complete neuroglial maturation in three cases, and a mixture of both in nine cases. Three-year progression-free survival was 37% and was significantly better in children older than 5 years of age. There was one death related to the HDCT. CONCLUSIONS: Preoperative chemotherapy is feasible and safe in children with high-risk medulloblastomas provided that the hydrocephalus can be treated at diagnosis. A larger study is warranted to ensure that the high response rate to adjuvant chemotherapy can lead to better surgical results and survival advantage.

Cerebellar Neoplasms↗
PubMed2004

High-dose chemotherapy followed by locoregional irradiation improves the outcome of patients with international neuroblastoma staging system Stage II and III neuroblastoma with MYCN amplification.

BACKGROUND: The objective of this study was to determine whether systemic and regional, intensified treatment can improve the outcome of children who present with a localized neuroblastoma (NB) with MYCN amplification (MNA). METHODS: Between 1990 and 2000, 610 children with localized NB were included in the Localized Neuroblastoma 90 (NBL 90) and NBL 94 study from the French Society of Pediatric Oncology. Among them, 32 children had MNA with Stage II or III NB. During the first period of the study, 20 children (Group A) received postoperative conventional chemotherapy (CT) and/or radiotherapy (RT), depending on each patient's postoperative status. Subsequently, because of a high recurrence rate, the next 12 children (Group B) were given postoperative high-dose CT (HDC) (busulfan and melphalan) with stem cell rescue (SCR) followed by RT in addition to conventional postoperative CT. RESULTS: The two groups were comparable with regard to prognostic factors (age, location of the primary lesion, International Neuroblastoma Staging System stage, lymph node invasion) and response to preoperative CT. The 6-year overall survival rate was significantly different between the two groups 25% +/- 10% in Group A vs. 83% +/- 11% in Group B; P = 0.004). CONCLUSIONS: Postoperative intensification treatment with HDC, SCR, and locoregional RT resulted in higher survival rates when compared with standard treatment alone and should be considered in the treatment plan for children who are diagnosed with Stage II or III NB and MYCN amplification.

Adolescent↗
PubMed2004

Alternative pathways of MYCN gene copy number increase in primary neuroblastoma tumors.

Neuroblastomas, tumors of the sympathetic nervous system, account for 7-10% of the cancers of childhood. Genetic studies have shown, and this study has confirmed, that neuroblastomas are very heterogeneous; no single genetic change common to all neuroblastomas has yet been identified. One genetic aberration found frequently in this pediatric tumor is MYCN gene amplification. Recently we identified a new subset of tumors showing MYCN gain (small increases in gene number arising from unbalanced translocation). To investigate whether gain precedes amplification or is an independent event, we surveyed 200 primary tumors for MYCN copy number with fluorescence in situ hybridization; 152 of 200 (76%) were MYCN single-copy tumors, whereas 48 of 200 (24%) tumors harbored MYCN abnormalities: 36 of the 48 (75%) had MYCN amplification and 12 (25%) had MYCN gain. Among the 36 with MYCN amplified gene, we found four that also showed gain. In three tumors exhibiting simultaneous gain and amplification, these two events were detected in neighboring cells. In the fourth case we detected only MYCN gain in metastatic neuroblasts in the bone marrow, but both MYCN amplification and gain in the primary tumor. The detailed study of these four cases suggests that there may be several different mechanisms leading to increase in MYCN copy number. Further studies in other human malignancies are necessary to determine whether simultaneous gain and amplification are specific to neuroblastoma or constitute a general mechanism by which tumor cells can acquire selective growth advantage.

Child↗
PubMed2003

Long-term risk of second malignant neoplasms after neuroblastoma in childhood: role of treatment.

The aim of our study was to quantify the risk of second malignant neoplasms (SMNs) among long-term survivors of neuroblastoma and to study the influence of treatment on this risk. We studied data from 544 5-year survival patients diagnosed with neuroblastoma before age 16 years at 8 French and British treatment centres from 1948 to 1986. After an average follow-up of 15 years (range, 5-38 years), 12 children developed a total of 13 SMNs, whereas 1.19 were expected from general population rates. Among these SMNs, there were 5 thyroid and 3 breast cancers. Increases of the risks of SMN were observed with time since neuroblastoma diagnosis and attained age. In a multivariate analysis, the relative risk of SMN associated with radiotherapy was 4.3 (95% CI 0.8-78), whereas no increased risk of SMN was associated with the administration of chemotherapy as a whole (RR = 0.4, 95% CI 0.1-1.9). Young children treated for a neuroblastoma have significantly increased risks of SMN over 3 decades of follow-up. Radiotherapy treatment was found to be an important risk factor for developing SMNs, whereas no effect of chemotherapy was evidenced. Although our findings reflect the late effects of past therapeutic modalities, they underscore the importance of long-term surveillance of young children treated for a neuroblastoma. For these patients, many more years of follow-up are required to appreciate their overall risks of treatment-related SMNs.

Antineoplastic Agents↗
PubMed2003

Central nervous system metastases in neuroblastoma: radiologic, clinical, and biologic features in 23 patients.

BACKGROUND: Central nervous system (CNS) metastases rarely occur in patients with neuroblastoma, although recent reports suggest an increase in the rate. CNS recurrence may represent a different mechanism of spread than bone and bone marrow metastases and may be associated with unique genetic determinants. Further definition of the radiologic, clinical, and biologic features may provide clues to the predisposing factors and mechanisms of CNS dissemination. METHODS: A retrospective analysis of all children ages 0-21 years with Stage IV neuroblastoma who were diagnosed at the Institut Curie and the Institut Gustave-Roussy between 1985 and 2000 was performed with direct review of medical records and magnetic resonance images, computed tomography scans, and iodine-123 or iodine-131 metaiodobenzylguanidine scintiscans (MIBG scans). When tumor tissue was available, genetic analysis was performed using comparative genomic hybridization (CGH). RESULTS: Of 434 patients with Stage 4 disease, 23 children had the CNS as their site of first recurrence. The estimated risk of CNS recurrence was 8.0% at 3 years, with no significant change in risk over the 15-year period. Eleven patients had isolated CNS recurrences, and the remaining patients developed recurrences concomitantly in other sites. The sites of recurrences were parenchymal (n = 8 patients), parenchymal with meningeal (n = 7 patients), and meningeal alone (n = 8 patients). MIBG scans detected CNS lesions in only 43% of patients. Significant risk factors for CNS recurrence included lumbar puncture at diagnosis, ages 2-3 years, and MYCN gene amplification. Abnormalities that were identified using CGH, in addition to 2p24 amplification in 5/7, included gains of 17q and 18q and losses of 1p, 3p, 10q25-26, and 11q. CONCLUSIONS: The risk of CNS recurrence in patients with neuroblastoma is 8% at 3 years after diagnosis and has not increased in the last 15 years. Because the CNS often is the sole site of recurrence, either it may be a sanctuary site, or the biologic determinants of CNS metastasis may be unique. Elucidation of risk factors and pathogenesis may allow prevention of this fatal event. Cancer 2003;98:155-65.

Adolescent↗
PubMed2003

Correlation of early metastatic response by 123I-metaiodobenzylguanidine scintigraphy with overall response and event-free survival in stage IV neuroblastoma.

PURPOSE: Metaiodobenzylguanidine (MIBG), specifically taken up in cells of sympathetic origin, provides a highly sensitive and specific indicator for the detection of metastases in neuroblastoma. The aim of this study was to correlate early response to therapy by MIBG scan, using a semiquantitative scoring method, with the end induction response and event-free survival (EFS) rate in stage IV neuroblastoma. PATIENTS AND METHODS: Seventy-five children older than 1 year and with stage IV neuroblastoma had 123I-MIBG scans at diagnosis, after two and four cycles of induction therapy, and before autologous stem-cell transplantation. The scans were read by two independent observers (concordance > 95%) using a semiquantitative method. Absolute and relative (score divided by initial score) MIBG scores were then correlated with overall pretransplantation response, bone marrow response, and EFS. RESULTS: The pretransplantation response rate was 81%, and the 3-year EFS rate was 32%, similar to a concomitant group of 375 stage IV patients. The median relative MIBG scores after two, four, and six cycles were 0.5, 0.24, and 0.12, respectively. The probability of having a complete response or very good partial response before transplantation was significantly higher if the relative score after two cycles was < or = 0.5, or, if after four cycles, the relative score was < or = 0.24. Patients with a relative score of < or = 0.5 after two cycles or a score of < or = 0.24 after four cycles had an improved EFS rate (P =.053 and.045, respectively). CONCLUSION: Semiquantitative MIBG score early in therapy provides valuable prognostic information for overall response and EFS, which may be useful in tailoring treatment.

3-Iodobenzylguanidine↗
PubMed2003

Hepatic focal nodular hyperplasia in children previously treated for a solid tumor. Incidence, risk factors, and outcome.

BACKGROUND: The detection of hepatic nodules, particularly in patients treated for a previous malignancy, raises a diagnostic dilemma. Focal nodular hyperplasia (FNH) of the liver is an uncommon, benign tumor in children and must be differentiated from malignant hepatic lesions. The etiology of FNH is obscure, and its pathogenesis is poorly understood. FNH may be a reaction to localized vascular abnormalities and circulatory disturbances. The goal of the current study was to identify risk factors for the occurrence of FNH in children who had received prior treatment for a malignant tumor. METHODS: The current retrospective study examined 14 cases of FNH in pediatric patients who previously had been treated for a malignancy. Diagnosis was based on clinical and radiologic findings and was proven histologically in four cases. RESULTS: FNH lesions were discovered by chance during routine examination in 78% of patients. The incidence of FNH was particularly high in the current series (0.45%) compared with the incidence in the general pediatric population. High doses of alkylating agents (e.g., busulfan or melphalan), venoocclusive disease, and liver radiotherapy may be responsible for injury to the vascular endothelium and subsequent localized circulatory disturbances. FNH is characterized by the absence of complications after its detection; therefore, only close follow-up is recommended. CONCLUSIONS: FNH appears to be a late complication of an iatrogenic vascular disease in children with a history of malignancy.

Adolescent↗
PubMed2002

Dendritic cells for NK/LAK activation: rationale for multicellular immunotherapy in neuroblastoma patients.

Natural killer (NK)/lymphokine-activated killer (LAK) cell-based immunotherapy could be beneficial against major histocompatibility complex class I-negative tumor residual disease such as neuroblastoma (NB), provided that interleukin 2 (IL-2) or surrogate nontoxic NK cell stimulatory factors could sustain NK cell activation and survival in vivo. Here we show that human monocyte-derived dendritic cells (MD-DCs) promote potent NK/LAK effector functions and long-term survival, circumventing the need for IL-2. This study demonstrates (1) the feasibility of differentiating granulocyte colony-stimulating factor-mobilized hematopoietic peripheral blood stem cells (PBSCs) into high numbers of functional MD-DCs and NK/LAK cells in a series of 12 children with stage 4 neuroblastoma (NB); (2) potent DC-mediated NK cell activation in autologous settings; (3) the reciprocal capacity of NK/LAK cells to turn immature DCs into maturing cells electively capable of triggering NK cell functions; and (4) the unique capacity of maturing DCs to sustain NK cell survival, superior to that achieved in IL-2. These data show a reciprocal interaction between DCs and NK/LAK cells, leading to the amplification of NK cell effector functions, and support the implementation of DC/NK cell-based immunotherapy for purging the graft and/or controlling minimal residual disease after autologous stem cell transplantation.

Cell Survival↗
PubMed2002

Prognostic value of doppler-ultrasonography in hepatic veno-occlusive disease.

BACKGROUND: Currently, the severity of veno-occlusive disease (VOD) is graded retrospectively on the basis of the evolution of clinical and biological criteria. The objective of this study was to describe a noninvasive method capable of predicting the severity of this disease at the time of the diagnosis. METHODS: Seventy-one children who developed VOD after intensive myeloablative therapy with busulfan before hematopoietic stem cell transplantation were included in this study. Sixty-four patients underwent baseline ultrasonography (US) and Doppler examination before transplantation. All patients had posttransplantation US and Doppler examinations at the time of the clinical and biological diagnosis of VOD. Seven US morphological criteria and seven Doppler criteria were studied that yielded three individual scores: a US score, a Doppler score, and a total Doppler ultrasonography (DUS) score. RESULTS: In the univariate analysis, three of 7 US criteria, three of 7 Doppler criteria, and the three scores were correlated with the severity of VOD after transplantation and at the time of the diagnosis. In the multivariate analysis, two US criteria (splenomegaly and ascites) and one Doppler criterion (flow recorded in para-umbilical vein) were correlated with the severity of VOD. The multivariate analysis of the pooled US and Doppler criteria showed that the flow recorded in the para-umbilical vein was the only criterion significantly associated with the grade of VOD (P=0.0001). All patients with a US-Doppler score >9 developed grade 2 or 3 VOD. CONCLUSION: Postgraft US and Doppler examinations have a prognostic significance according to the grade of VOD.

Adolescent↗
PubMed2002

MYCN gene overrepresentation detected in primary neuroblastoma tumour cells without amplification.

Neuroblastoma is the most frequent solid extracranial neoplasm of childhood, with a median age of presentation of under 2 years. This tumour is highly malignant in patients older than 12 months of age with metastatic disease. Clinical studies have confirmed that amplification of the MYCN proto-oncogene is one of the best prognostic indicators of poor outcome. Approximately 30% of neuroblastoma tumours present MYCN amplification at diagnosis. Far less is known about the incidence and consequences of overrepresentation of the gene due to duplication or rearrangement of the chromosome arm in which the gene is situated. This study has analysed 110 neuroblastomas by FISH and has detected a gain of 1-3 copies per cell of MYCN in 8% of MYCN-non-amplified tumours. In these primary tumours, cells gained small numbers of additional MYCN genes by two mechanisms: formation of an isochromosome 2p, or an unbalanced translocation involving the short arm of chromosome 2 (with MYCN) and various partner chromosomes. Quantitative RT-PCR showed three- to seven-fold elevated MYCN expression in three tumours. Although the follow-up time to date is still short, clinical outcome suggests that low-level overexpression of the MYCN gene does not enhance tumour aggressiveness and rapidity of disease progression, as is often seen in neuroblastoma with MYCN amplification. It is hypothesized that the small elevation in MYCN expression could alter the regulation of apoptosis, as has been shown in experimental models.

Chromosomes, Human, Pair 2↗
PubMed2002

[Difficulties in coping with treatment: causes, solutions].

We present a case of parents who had difficulties accepting their child's treatment (HD chemotherapy and stem cell transplantation) and coping with it. The conversation between the paediatrician and the mother revealed that she feared being dispossessed of her maternal role by the nurses, that constraints would interfere with her relationship with her son, that the medical team would make her feel intellectually, culturally and socially inferior, that the conflict the couple was facing would be exacerbated in this setting. Collaboration between the paediatrician, the nursing staff and the psycho-oncologist allowed these conscious and unconscious elements to be understood. Talking, not conflict nor constraints, served to allay their fears, to avoid inappropriate reactions of the medical team, to preserve the therapeutic alliance. The child accepted this trying treatment because he saw that his parents were reassured about its quality and about preserving their sense of identity and their value. Coping difficulties may stem from fear of treatment (too trying physically and psychologically), from its consequences (destabilisation of the family, the individual's social and professional status, his/her sense of identity), from rekindled old problems that were not adequately solved (jealousy, revolt, trauma, bereavement). Dialogue and team work are necessary to solve them.

Attitude of Health Personnel↗