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D Couanet

Publications and source records attributed to D Couanet.

At least 19 recordsLinked to original sources

[Imaging of childhood brain tumors].

Brain tumors represent around a quarter of all solid tumors observed in the pediatric population. Infratentorial tumors are the most frequent, mostly encountered between 4 and 11 years of age. Early imaging is important because initial symptoms can be misinterpreted as statural and pubertal disorders or pseudoabdominal symptoms with apathy and vomiting in infants. Because signal abnormalities on MRI are most often not specific, it is essential to take into account the clinical and topographic characteristics of the lesion to establish an appropriate differential diagnosis. The main patterns of brain tumors observed in pediatrics are presented. Brain metastases are very unusual in children, in contrast to lepto-meningeal metastasis.

Adolescent↗

Dose finding and O6-alkylguanine-DNA alkyltransferase study of cisplatin combined with temozolomide in paediatric solid malignancies.

Cisplatin may have additive activity with temozolomide due to ablation of the DNA repair protein O6-alkylguanine-DNA alkyltransferase (MGMT). This phase I/II study determined recommended combination doses using the Continual Reassessment Method, toxicities and antitumour activity in paediatric patients, and evaluated MGMT in peripheral blood mononuclear cells (PBMCs) in order to correlate with haematological toxicity. In total, 39 patients with refractory or recurrent solid tumours (median age approximately 13 years; 14 pretreated with high-dose chemotherapy, craniospinal irradiation, or having bone marrow involvement) were treated with cisplatin, followed the next day by oral temozolomide for 5 days every 4 weeks at dose levels 80 mg m(-2)/150 mg m(-2) day(-1), 80/200, and 100/200, respectively. A total of 38 patients receiving 113 cycles (median 2, range 1-7) were evaluable for toxicity. Dose-limiting toxicity was haematological in all but one case. Treatment-related toxicities were thrombocytopenia, neutropenia, nausea-vomiting, asthenia. Hearing loss was experienced in five patients with prior irradiation to the brain stem or posterior fossa. Partial responses were observed in two malignant glioma, one brain stem glioma, and two neuroblastoma. Median MGMT activity in PBMCs decreased after 5 days of temozolomide treatment: low MGMT activity correlated with increased severity of thrombocytopenia. Cisplatin-temozolomide combinations are well tolerated without additional toxicity to single-agent treatments; the recommended phase II dosage is 80 mg m(-2) cisplatin and 150 mg m(-2) x 5 temozolomide in heavily treated, and 200 mg m(-2) x 5 temozolomide in less-heavily pretreated children.

Adolescent↗

High-dose busulfan and thiotepa followed by autologous stem cell transplantation (ASCT) in previously irradiated medulloblastoma patients: high toxicity and lack of efficacy.

We previously demonstrated that Busulfan-Thiotepa (Bu-Thio) and ASCT effectively treated patients with locally relapsed medulloblastoma after surgery and conventional chemotherapy. We thus evaluated the administration of Bu-Thio in patients relapsing after conventional CNS irradiation. Patients were scheduled to receive Busulfan (600 mg/m(2)) and Thiotepa (900 mg/m(2)) and ASCT. Resection of residual tumour and additional irradiation were performed if necessary and feasible after Bu-Thio. Toxicity was compared to that observed in 35 patients treated without previous CNS irradiation. From 5/88 to 3/02, 15 patients were treated according to this strategy. Toxicity was significantly higher than that observed in unirradiated patients: thrombocytopenia <50,000/mm(3) lasting 56 days (13-732) (P=0.02) and 30 days (4-124), respectively, HVOD (10/15 and 12/35 patients, respectively) (P=0.06), neurological toxicity (8/15 vs 3/35 patients) (P=0.01). Tumour response was assessable in seven patients and consisted in two CR, three PR and two NR. Currently, two of 15 patients are alive with no evidence of disease. In conclusion, the toxicity of Bu-Thio was significantly more severe in previously irradiated patients. In spite of a high response rate, this strategy failed to improve the prognosis of previously irradiated patients with a relapse from a medulloblastoma.

Adolescent↗

Temozolomide in paediatric high-grade glioma: a key for combination therapy?

This report describes a single-centre study with temozolomide (TMZ) (200 mg m(-2) day(-1) x 5 per cycle of 28 days) in children with (recurrent) high-grade glioma. Magnetic resonance imaging was performed every two cycles. In all, 20 patients were treated between 1998 and 2001 after the UKCCSG/SFOP TMZ phase II trial. All patients had measurable disease. Totally, 15 patients had a relapse after surgery+/-radiotherapy+/-chemotherapy. Overall, five patients received TMZ after surgery or biopsy, awaiting radiotherapy. There were one clinically malignant grade II glioma, 11 grade III and eight grade IV gliomas. Seven tumours had oligodendroglial features. Mean age at start of TMZ was 12.0 years (range 3-20.5 years). In total, eight patients had >8 cycles (range 3-30). One VGPR (currently in CR after surgery), three PRs (with a PFS of 4, 4 and 11 months, respectively) and one MR (PFS 14 months) were observed. Three out of five responses occurred after >4 courses. The overall response rate was 20%. Median progression-free survival (PFS) was 2.0 months (range 3 weeks-34+ months). PFS rate was 20% after 6 months. Median overall survival (OS) was 10 months. Nine patients showed a clinical improvement. Three patients vomitted shortly after TMZ administration, eight patients (13 cycles) experienced grade III/IV thrombocytopenia, occurring predominantly during the fourth week of the first two cycles. Five patients experienced neutropenia, and three patients febrile neutropenia. TMZ is a well-tolerated ambulatory treatment for children with malignant glial tumours. This drug warrants further study in these highly chemoresistant tumours and should be studied either as upfront therapy or in combination therapy.

Administration, Oral↗

Localized cervical neuroblastoma: prevention of surgical complications.

OBJECTIVES: The purpose of this study focused on cervical neuroblastoma (NB) was to assess the prognosis, define the most suitable methods of investigation, and evaluate risk factors for complications following primary surgery. METHODS: Between 1990 and 1999, we conducted two consecutive prospective multicentric studies (NBL90 and NBL94) on localized NB. Because the first study (1990-1994) found surgery-related morbidity and mortality, several surgical risk factors (i.e. adhesion to major vessels, size, friability, and dumb bell tumor) were defined and used prospectively as criteria of resectability in the second study (1994-1999). RESULTS: Of 617 cases included in the two studies, 43 involved cervical NB including 17 cervicothoracic tumors. With a median follow-up of 4 years, overall survival and event-free survival rates were 91 and 81%, respectively with no significant difference between cervical or cervicothoracic NB. Seventeen patients were included in the second study; surgery was used as the first line treatment in 11. Full pre-operative work-up was performed in eight patients, demonstrating one or more risk factors in three. The remaining three patients underwent emergency surgery with no pre-operative work-up or only ultrasound: two developed serious complications. All three patients presenting documented risk factors developed post-operative complications versus only two of the eight patients who presented no risk factor (n = 5) or were inadequately evaluated (n = 3) (P = 0.06). None of the five patients in whom full work-up demonstrated no risk factor had post-operative complications (P = 0.02). CONCLUSIONS: Cervical neuroblastoma has a favorable prognosis. Surgery is the treatment of choice but there is a risk of complications. Appropriate pre-operative work-up is mandatory to evaluate resectability. The surgical risk factors defined for our second study seem to be significant predictors of post-operative complications.

Female↗

Temozolomide in malignant gliomas of childhood: a United Kingdom Children's Cancer Study Group and French Society for Pediatric Oncology Intergroup Study.

PURPOSE: To determine the response rate of the malignant gliomas of childhood to an oral, daily schedule of temozolomide. PATIENTS AND METHODS: A multicenter, phase II evaluation of an oral, daily schedule of temozolomide (200 mg/m(2) on 5 consecutive days) was undertaken in children with relapsed or progressive, biopsy-proven, high-grade glioma (arm A) and progressive, diffuse, intrinsic brainstem glioma (arm B). Evidence of activity was defined by radiologic evidence of a sustained reduction in tumor size on serial magnetic resonance imaging scans. RESULTS: Fifty-five patients were recruited (34 to arm A and 21 to arm B) and received 215 cycles of chemotherapy. Grade 3/4 thrombocytopenia was the most frequent toxic event (7% of cycles). Prolonged myelosuppression resulted in significant treatment delays and dose reductions (17% and 22% of cycles, respectively). Two toxic deaths were documented and were related to myelosuppression and sepsis in one patient and pneumonia in a second. The overall (best) response rate was 12% for arm A (95% confidence interval [CI], 3 to 28 in the study cohort, and 2 to 31 for eligible patients) and 5% and 6%, respectively, for arm B (95% CI, 0 to 26 in the study cohort, and 0 to 27 for eligible patients). Stabilization of disease was also documented and was most noteworthy for brainstem gliomas, where two patients achieved both radiologic static disease and discontinued steroid medication. CONCLUSION: Despite moderate toxicity, objective response rates to temozolomide have been low, indicating that temozolomide has minimal activity in the high-grade gliomas of childhood.

Adolescent↗

[Pseudotumoral diseases: ten years of experience in a pediatric oncology department].

PURPOSE: Among the 350 new patients per year treated in the pediatric oncology department of the Gustave-Roussy Institute, about 2% have no tumor. This study analyzes these children presenting a pseudotumoral disease. PATIENTS AND METHODS: Ten-year-retrospective study. Patients for which no follow up in oncology was necessary after one consultation or hospitalization were selected. OUTCOME: Between 1990 and 2000, 64 patients were seen in the pediatric department for pseudotumoral disease. The reasons of orientation were mainly a soft tissue mass (15 cases), an abdominal mass (14 cases), or a bone lesion (13 cases). Diagnosis was most often infectious diseases (33 cases), or post-traumatic lesions (10 cases). Diagnosis was established following several consultations or an hospitalization for 29 of 64 patients. In 75% of the cases new investigations were necessary to determine the diagnosis. A biopsy was performed in 19. For two children, diagnosis was corrected after the beginning of chemotherapy. CONCLUSION: Pseudotumoral diseases leading to a consultation in pediatric oncology are rare and represent two per cent of the patients. For these difficult cases, only a pluridisciplinary discussion may lead to diagnosis.

Abdominal Neoplasms↗

Phase II trial of thalidomide in renal-cell carcinoma.

BACKGROUND: Thalidomide has been reported to yield anti-tumor activity in cancer. We performed a phase II trial of this drug in patients with metastatic renal cell carcinoma to determine its efficacy. PATIENTS AND METHODS: Patients with proven metastatic renal cell cancer, measurable progressive disease and a performance status of 0-2 were enrolled in this study. Thalidomide was given daily at a starting dose of 400 mg, followed by a 400 mg increment to 800 mg and then to 1200 mg with 6-12 weeks at each dose level. The response rate at 6 months was the primary end point. Toxicity, overall survival, tumor vascularization depicted on color Doppler ultrasonography and serum vascular endothelial growth factor, basic fibroblast growth factor, interleukin-12 and tumor necrosis factor-alpha levels were secondary end points. RESULTS: Forty patients were enrolled. Two partial responses were observed (5%) and disease remained stable in nine patients after 6 months. Median survival was 10 months. Toxicity was high, with frequent manifestations of fatigue, constipation and lethargy. The incidence of neuropathy detected on electromyography (EMG) attained 70% at 6 months, and 100% in patients on thalidomide for 12 months. Nine patients developed venous thromboembolism during the first 12 weeks of treatment, and three of them experienced pulmonary embolism. One unexpected (and unexplained) death occurred. CONCLUSIONS: Despite undisputed, albeit marginal, activity in renal cell cancer, high-dose thalidomide cannot be recommended using this schedule since the level of toxicity is high.

Adult↗

Postoperative chemotherapy without irradiation for ependymoma in children under 5 years of age: a multicenter trial of the French Society of Pediatric Oncology.

PURPOSE: To evaluate a strategy that avoids radiotherapy in first-line treatment in children under 5 years of age with brain or posterior fossa ependymoma, by exclusively administering 16 months of adjuvant multiagent chemotherapy after surgery. PATIENTS AND METHODS: Between June 1990 and October 1998, 73 children with ependymoma (82% with high-grade tumors) were enrolled onto this multicenter trial. Children received adjuvant conventional chemotherapy after surgery consisting of seven cycles of three courses alternating two drugs at each course (procarbazine and carboplatin, etoposide and cisplatin, vincristine and cyclophosphamide) over a year and a half. Systematic irradiation was not envisaged at the end of chemotherapy. In the event of relapse or progression, salvage treatment consisted of a second surgical procedure followed by local irradiation with or without second-line chemotherapy. RESULTS: Conventional chemotherapy was well tolerated and could be administered in outpatient clinics. No radiologically documented response to chemotherapy more than 50% was observed. With a median follow-up of 4.7 years (range, 5 months to 8 years), the 4-year progression-free survival rate in this series was 22% (95% confidence interval [CI], 13% to 43%) and the overall survival rate was 59% (95% CI, 47% to 71%). Overall, 40% (95% CI, 29% to 51%) of the patients were alive having never received radiotherapy 2 years after the initiation of chemotherapy and 23% (95% CI, 14% to 35%) were still alive at 4 years without recourse to this modality. In the multivariate analysis, the two factors associated with a favorable outcome were a supratentorial tumor location (P =.0004) and complete surgery (P =.0009). Overall survival at 4 years was 74% (95% CI, 59% to 86%) for the patients in whom resection was radiologically complete and 35% (95% CI, 18% to 56%) for the patients with incomplete resection. CONCLUSION: A significant proportion of children with ependymoma can avoid radiotherapy with prolonged adjuvant chemotherapy. Deferring irradiation at the time of relapse did not compromise overall survival of the entire patient population.

Antineoplastic Combined Chemotherapy Protocols↗

Pharmacodynamics of tandem high-dose melphalan with peripheral blood stem cell transplantation in children with neuroblastoma and medulloblastoma.

Repeated high-dose (HD) chemotherapy with peripheral blood stem cell (PBSC) transplantation is a new modality aimed at increasing both the dose and its intensity in the treatment of chemosensitive tumours. The aim of this study was to evaluate the tolerance, pharmacokinetics (PK) and pharmacodynamics (PD) of HD single-agent melphalan administered over two consecutive courses (C1 and C2) in children. Twenty-one patients (10 girls) with a median age of 4.1 years (range 8 months-14 years) were entered into this study. Five had metastatic neuroblastoma (NB) and 16 a cerebral primitive neuroectodermal tumour (PNET). Melphalan was given at a dose of 100 mg/m(2) every 21 days. PBSCs were infused at a median number of 2.98 x 10(6) CD34(+) cells/kg. Forty courses, ie 21 C1 and 19 C2, were administered. Both courses were well tolerated. The median duration of ANC < 500/microl was 7 and 6 days after C1 and C2, respectively. Platelet recovery (not mandatory to continue the HD strategy) was achieved in 52% of courses. GI toxicity was mild to moderate. The melphalan AUC ranged from 177 to 475 microg small middle dotmin/ml (no difference between C1 and C2). Prolonged neutropenia was associated with a young age (P < 0.001) and a low amount of CFU-GM (P = 0.002). A long time to platelet recovery was associated with a high AUC (P = 0.004) and a young age (P = 0.02). Grade 1 or 2 GI toxicity was associated with a high AUC (P = 0.015). Partial remission was observed in 11/14 patients with measurable cerebral PNET. In conclusion, tandem HD melphalan is feasible and safe in children, and achieved a high response rate in cerebral PNET. The observed PK-PD relationships may help us design PK-guided outpatient treatment.

Adolescent↗

Visual agnosia after treatment of a posterior fossa ependymoma in a 16-month-old girl.

We present the clinical observation of a 16-month-old girl treated for a posterior fossa ependymoma who experienced severe and delayed visual dysfunction. She was initially treated by surgery and conventional chemotherapy. When she relapsed at age 3 years, the salvage treatment combined high-dose chemotherapy, second surgery, and local irradiation. At age 4 years, disturbed gait and dysarthric speech appeared rapidly, and she became unable to recognize objects and people. Computed tomography revealed bilateral calcifications in the cerebellum and temporal and occipital lobes but no relapse. The neuropsychologic evaluations revealed signs of visual agnosia and marked intellectual impairment. The role of the different treatment modalities in the pathogenesis of this unusual syndrome is discussed.

Agnosia↗

[A protocol for imaging pediatric brain tumors].

Children with malignant brain tumors undergo multicentric clinical trials to improve standards of care. The considerable variations in imaging practice can serve as confounding variables in these studies. The purpose of this report is to propose a set of standard diagnostic imaging guidelines to improve the value of imaging when used to test the efficacy of treatments in pediatric neuro-oncology.

Brain Neoplasms↗

[Current strategy for the imaging of neuroblastoma].

Advances in the management of neuroblastoma lead radiologists and nuclear medicine specialists to optimize their procedures in order to propose a rational use of their techniques, adjusted to the various clinical presentations and to therapeutic management. The aim of this paper is to assess the imaging procedures for the diagnosis and follow-up of neuroblastoma in children according to current therapeutic European protocols. An imaging strategy at diagnosis is first proposed: optimal assessment of local extension of the primary tumour is made with MRI, or spiral-CT when MRI is not available, for all locations except for abdominal tumours for which CT remains the best imaging modality. Metastatic extension is assessed with mIBG scan and liver sonography. Indications for bone metastasis evaluation with either radiological or radionuclide techniques are detailed. Imaging follow-up during treatment for metastatic or unresectable tumours is described. A check-list of radiological main points to be evaluated before surgery is proposed for localized neuroblastoma. The imaging strategy for the diagnosis of "occult" neuroblastoma is considered. Finally, we explain the management of neuroblastoma detected during the prenatal or neonatal period.

Biopsy↗

Consolidation with a busulfan-containing regimen followed by stem cell transplantation in infants with poor prognosis stage 4 neuroblastoma.

Although infants with stage 4 neuroblastoma (NB) usually have a good prognosis, metastatic relapses after 1 year of age and amplification of the N-myc oncogene are established poor prognostic factors. In order to improve the survival of patients with such high-risk factors, we performed consolidation with a busulfan (600 mg/m2)-melphalan (140 mg/m2)-containing regimen followed by autologous stem cell transplantation (SCT). From 1986 to 1998, 12 patients were treated according to this strategy. Their median age at diagnosis was 9 months (1-11). Consolidation was performed after a metastatic relapse in five children, because of persistent bone metastases in one and as first-line consolidation in six patients whose tumor exhibited N-myc amplification. The 5-year EFS rate is 64. 5% (36-85%) with a median follow-up of 92 months (20-126). One toxicity-related death occurred in a very heavily pretreated patient. Hepatic veno-occlusive disease was the major side-effect that occurred in nine of 12 children. This busulfan-melphalan combination appears to dramatically improve the prognosis of these high-risk infants with metastatic NB. Given its high toxicity, indications for this consolidation must be restricted to high-risk infants and a lower dose of busulfan (480 mg/m2) is recommended in children weighing less than 10 kg. Bone Marrow Transplantation (2000) 25, 937-942.

Antineoplastic Combined Chemotherapy Protocols↗

The role of radiation therapy in the management of craniopharyngioma: a 25-year experience and review of the literature.

PURPOSE: To review the outcome and quality of life at 5 years and more of 37 children treated with radiation therapy combined or not with surgical resection for a craniopharyngioma in a single institution. METHODS AND MATERIALS: From January 1969 through December 1992, 37 children received external therapy at the Institut Gustave Roussy (Villejuif, France). Age ranged between 1 and 15 years (mean 7.4), M/F sex ratio was 0.76. In approximately one-half of the cases (18/37), radiation therapy was applied in conjunction with a surgical resection, and in almost one-half of the cases (18/37) as part of a salvage program following local failure. Total dose ranged between 45 and 56 Gy (median 50) given with a conventional fractionation in most children. Survival (S), event-free survival (EFS) were computerized according to the Kaplan-Meier method and prognostic factors for local failure and functional status analyzed. Functional outcome was evaluated according to the Wen score in 4 grades (gr 1: normal with/without hormonal replacement, gr 4: totally dependent, gr 2 and 3: intermediate disabilities). RESULTS: At the time of analysis, 24 children (65%) were alive with NED, 4 (11%) alive after failure, and 9 (24%) dead of various causes. Following therapy, S and EFS regularly degraded and didn't seem to reach a plateau before 9 years (5 and 10 year S and EFS, respectively, 91, 65, and 78 and 56.5%). This was due to the occurrence of late failures (5 and 8.5 years) and late lethal complications (1 in-field glioblastoma multiforme at 9 years). A significant gain on EFS followed the introduction of modern imaging (p = 0.03), the association of surgical resection with RT (p = 0.01) and of higher doses of radiation superior or equal to 55 Gy (p = 0.05); a similar gain on S was observed in patients with a good initial performance status (p = 0.05). It is remarkable that surgical salvage of local failures following RT could induce prolonged remission in 4 children. Functional outcome was impaired in all but 5 children out of 35 fully evaluable (86%) and related with the initial symptomatology and/or therapy. Endocrinological, visual, neurological functions were affected in 97, 34, and 40%, respectively. It appeared correlated with the initial performance status (p = 0.02) and possibly with a younger age at treatment (p = 0.07). CONCLUSIONS: Long-term follow-up beyond 5 years is warranted in craniopharyngioma to assess tumor control and functional outcome after radiation therapy. Although this therapeutical modality provides a high cure rate alone or in combination with surgery and even though at the time of failure, further strategies should aim to limit the severe toxicity (i.e., Wen gr 3 + 4) that was observed in more than one-third of our patients.

Child↗

Radiation-induced cerebral vasculopathy in children with neurofibromatosis and optic pathway glioma.

Occlusive vasculopathy is a potential complication of radiotherapy in children with optic pathway glioma. With a median follow-up of 7 years, 13 of 69 children in this study developed clinical and radiological signs of occlusive vasculopathy after radiotherapy within a median interval of 36 months. The major risk factor was neurofibromatosis type 1. Radiotherapy should no longer be the first treatment in these settings. When radiotherapy is unavoidable, regular screening for cerebral vasculopathy is mandatory, as preventive treatment is available.

Cerebrovascular Disorders↗

Chemotherapy for unresectable and recurrent intramedullary glial tumours in children. Brain Tumours Subcommittee of the French Society of Paediatric Oncology (SFOP).

Adjuvant treatment for intramedullary tumours is based on radiotherapy. The place of chemotherapy in this setting has yet to be determined. Between May 1992 and January 1998, eight children with unresectable or recurrent intramedullary glioma were treated with the BB SFOP protocol (a 16-month chemotherapy regimen with carboplatin, procarbazine, vincristine, cyclophosphamide, etoposide and cisplatin). Six children had progressive disease following incomplete surgery and two had a post-operative relapse. Three patients had leptomeningeal dissemination at the outset of chemotherapy. Seven of the eight children responded clinically and radiologically, while one remained stable. At the end of the BB SFOP protocol four children were in radiological complete remission. After a median follow-up of 3 years from the beginning of chemotherapy, all the children but one (who died from another cause) are alive. Five patients remain progression-free, without radiotherapy, 59, 55, 40, 35 and 16 months after the beginning of chemotherapy. The efficacy of this chemotherapy in patients with intramedullary glial tumours calls for further trials in this setting, especially in young children and patients with metastases.

Antineoplastic Combined Chemotherapy Protocols↗

Prognostic factors in metastatic neuroblastoma in patients over 1 year of age treated with high-dose chemotherapy and stem cell transplantation: a multivariate analysis in 218 patients treated in a single institution.

The purpose of this paper is to study prognostic factors in neuroblastoma patients treated with high-dose chemotherapy and hematopoietic stem cell transplantation. Two hundred and eighteen children over 1 year of age and treated for stage 4 neuroblastoma were enrolled in this study. The median age at diagnosis was 39 months, the sex ratio 1.5 and 84% of patients had an abdominal primary tumor. Skeletal disease was detected in 79% of cases and bone marrow involvement in 93%. N-myc oncogene amplification was present in 27% of the patients studied. The probability of event-free survival at 5 years post-diagnosis was 29% in this series. Three major favorable prognostic factors were significant and independent in the multivariate analysis: age under 2 years at diagnosis (P<0.01), absence of bone marrow metastases at diagnosis (P<0.04) and the high-dose conditioning regimen containing busulfanmelphalan combination (P = 0.001). The quality of response to conventional primary chemotherapy was close to significance (P = 0.053). We conclude that factors related to the patient (age) and extent of disease are predictive of outcome in patients with neuroblastoma treated with conventional chemotherapy followed by surgical excision of the primary and consolidation with high-dose chemotherapy. They should be taken into account in future prospective studies. Moreover, the type of conditioning regimen appears to be the most important prognostic factor. This should encourage new investigations into innovative drug combinations.

Adolescent↗