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D Couanet

Publications and source records attributed to D Couanet.

At least 19 recordsLinked to original sources
PubMed1996

Phase I study of high-dose continuous intravenous infusion of VP-16 in combination with high-dose melphalan followed by autologous bone marrow transplantation in children with stage IV neuroblastoma.

The purpose of the study was to determine the maximum tolerated dose of continuous infusion of high-dose VP-16 in combination with high-dose melphalan (HDM) for conditioning before autologous bone marrow transplantation (ABMT). Thirteen children (median age 27 months) with stage IV neuroblastoma were treated with high-dose VP-16 and HDM followed by ABMT as consolidation treatment. All had previously received conventional chemotherapy with a mean number of six drugs. Surgery of the primary tumor had been performed in 12/13. We performed a dose-escalating study of VP-16 from 1800 mg/m2/72 h with 300 mg/m2/72 h dose increments according to toxicity. VP-16 was administered as a 72-h i.v. infusion. Melphalan (140 mg/m2/day) was administered once as an i.v. push. VP-16 pharmacokinetics were analyzed in 12 patients. Five children received 1800 mg/m2/72 h of VP-16, five received 2100 mg/m2/72 h and three, 2400 mg/m2/72 h. The mean duration of granulocytopenia (< 0.5 x 10(9)/1) was 24 days and thrombocytopenia (< 50 x 10(9)/1) was 36 days. No major infectious complications occurred. Gastrointestinal (GI) toxicity was the dose-limiting toxicity. Five severe manifestations of GI toxicity in three patients led us to consider 2400 mg/m2/72 h as the MTD. The mean VP-16 clearance rate was 17.3 ml/min/m2 with continuous infusion. A mean steady-state plasma concentration of 24.2 micrograms/ml (s.d. = 2) and 28.3 micrograms/ml (s.d. = 1.9) was achieved at the 1800 mg/ml and 2100 mg/m2 dose levels, respectively, GI toxicity is dose limiting when VP-16 at 2400 mg/m2/72 h, is associated with HDM. When given as a continuous i.v. infusion, at 2100 mg/m2/72 h, VP-16 associated with HDM is well tolerated before ABMT in young heavily pre-treated children.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1996

[Retrospective analysis of 44 adrenal puncture biopsies under x-ray computed tomographic guidance].

Fourty-four CT-guided adrenal biopsies were performed on 43 patients aged 12-74 years old (mean 57 years). The results (benign adrenal tissue, malignant tissue, and nondiagnostic) were compared with outcomes. Diagnostic samples were obtained in 86% of patients. Among the 37 proved cases with diagnostic results (10 benign, 27 malignant), there were 26 true-positives, 1 false-negatives and 10 true-negatives. CT-guided adrenal biopsy had an accuracy of 82%, a sensitivity of 96%, a negative predictive value of 83%. In the 6 patients with nondiagnostic samples 1 mass proved malignant and two masses proved benign. Seven minor complications occurred in 7 patients (6 pneumothoraces and 1 retroperitoneal hemorrhage). CT-guided adrenal biopsy is a simple safe and well tolerated technique. In oncologic patients, obtaining benign adrenal tissue was highly predictive of benignity.

Adolescent↗
PubMed1995

[Research on bone marrow involvement in the diagnosis of solid tumors in children. Methods, results and interpretation].

The assessment of bone marrow involvement by tumor cells remains an essential problem at diagnosis in pediatric solid tumors. Besides the conventional cytological and histological methods, some modern cell density separation techniques have been described in order to improve the detection of minimal or scattered bone marrow involvement. Immunological or genetical (molecular biology) tools can be used for the recognition of separated cells. In terms of investigations, MRI and MIBG radionucleide scan, although giving no definite proof, have the ability to macroscopically study the scattering of bone marrow invasion in the particular case of neuroblastoma. In some pediatric tumors, especially neuroblastomas and non Hodgkin lymphomas, an extensive bone marrow investigation is mandatory at diagnosis. Such an investigation is only necessary in case of particular criteria at diagnosis of Hodgkin's disease, Ewing' sarcomas, rhabdomyosarcomas and retinoblastomas. All other pediatric solid tumors do not need to be investigated in terms of bone marrow involvement at diagnosis, with the exceptions of advanced disseminated disease or if an autologous bone marrow transplantation is planned.

Bone Marrow Diseases↗
PubMed1994

What is the prognostic value of osteomedullary uptake on MIBG scan in neuroblastoma patients under one year of age?

Twenty-seven infants under one year of age with metastatic neuroblastoma were studied for osteomedullary metastases. They were evaluated by at least two imaging procedures: X-ray films and MIBG scan. Taking into account the results of these investigations, 3 groups were defined: osteomedullary metastases were detected in 8 infants by both X-ray and MIBG scan, no osteomedullary sites were detected by either technique in 13 patients, and 6 had osteomedullary foci with positive MIBG uptake but no radiological abnormality. These three groups were apparently different in terms of median age, response to chemotherapy, and long-term survival. The third group, which has not been previously described, appears to have a better prognosis than patients with radiologically detectable bone lesions. Nevertheless it was necessary to use intensive chemotherapy to obtain remission in these particular patients. It should be mandatory to specify the investigatory technique used to describe osteomedullary metastases in infants and treatment should be adapted according to this grouping system.

3-Iodobenzylguanidine↗
PubMed1994

Super-high-risk germ-cell tumors: a clinical entity. Report of eleven cases.

Among patients suffering from nonseminomatous germ-cell tumor, with a poor prognosis, a subset underwent respiratory failure and died very early in the course of their treatment. Between 1982 and 1989, 11 out of 56 such patients (20%) died within the first 5 weeks of chemotherapy. The clinical, radiological, biological and infectious characteristics of these patients were analyzed. Nine patients had extensive pulmonary metastases and the 2 others presented a bulky mediastinal mass with pleural effusion. All patients experienced acute respiratory distress during chemotherapy and underwent mechanical ventilation. All patients were febrile, and septicemia was documented in 7 cases. WHO grade 4 and grade 1-2 renal toxicities occurred in 3 and 4 patients respectively. There was no tumor lysis syndrome. All patients died within 35 days from the start of therapy; 4 were autopsied. These 11 patients represent a clinical entity, having what we called super-high-risk germ cell tumors. Early death is related to pulmonary distress within the first 5 weeks of therapy. The origin of the pulmonary distress is multifactorial: bulky disease of the chest, infection, and interstitial fibrosis. Immediate full-dose standard chemotherapy in association with intensive supportive care is recommended in the management of these patients.

Adult↗
PubMed1994

Head and neck rhabdomyosarcomas in children: value of clinical and CT findings in the detection of loco-regional relapses.

Between 1984 and 1990, 16 children who had been treated for a histologically proven head and neck rhabdomyosarcoma developed 19 local recurrences. Fourteen relapses discovered in 11 children (group 1) were based on clinical data acquired 3 to 52 months after completion of treatment. Clinical symptoms (12 patients) or examination (2 patients) led to suspicion of a relapse. The clinical presentation of relapses and that of primary tumour were identical in eight cases. CT scans performed prior to recurrence revealed a stable 'post-therapeutic residue' without mass effect at the original site (12 patients) or was normal (2 patients). Six of these 11 children died at 1 to 15 months and five are alive 12 to 36 months after treatment of recurrence. Five relapses were discovered on CT studies 3 to 15 months after completion of treatment in the remaining five children (group 2). Clinical examination was normal in all cases. CT scans performed 3 months before recurrence showed a stable 'post-therapeutic residue' (4 patients) or was normal (1 patient). All of these five children died 3 to 23 months after the relapse.

Adolescent↗
PubMed1993

Bone metastases as the presenting manifestation of rhabdomyosarcoma in childhood.

Rarely, rhabdomyosarcoma can present with bone pain and bone lesions on radiographs without evidence of a primary tumor. Of 428 children with biopsy-proven rhabdomyosarcoma, four presented with radiographic evidence of bone metastases, but no primary tumor was found on subsequent evaluation. On radiographs, these metastases, located most commonly in the metaphyses of the extremities and in the spine, displayed a destructive or diffusely permeative pattern without sclerotic margins and mimicked the more common neuroblastoma. One patient also had diaphyseal cortical lytic metastases of the tibia. Radiographs defined metastases of the extremities better than the correlative bone scans. In the spine, on T2-weighted magnetic resonance (MR) images, metastases displayed high signal intensity which contrasted with the low-signal-intensity marrow in these pediatric patients. On histopathologic examination, metastatic rhabdomyosarcoma was composed of small cells of variable size, shape, and growth pattern similar to other round cell tumors. A positive desmin immunohistochemical test helped to establish the diagnosis. The radiologist, pathologist, and clinician should be aware of this unusual presentation of rhabdomyosarcoma so that suitable immunohistochemical tests are performed and appropriate chemotherapy given.

Adolescent↗
PubMed1993

Extraskeletal mesenchymal chondrosarcoma.

Among seven patients with extraskeletal mesenchymal chondrosarcoma (EMC), three children (aged 3-6 years) developed EMC in a central location and four adults (aged 38-54 years) developed EMC in both central and peripheral sites. Conventional radiography and tomography and computed tomography (CT) depicted EMC as a soft-tissue mass with ring, arc, stippled, and highly opaque calcifications in four patients. Contrast-enhanced CT showed lobulation and peripheral tumoral enhancement, sometimes with central low-attenuation areas. On magnetic resonance (MR) images, EMC was a lobulated mass with high signal intensity on T2-weighted images and enhancement with low-signal-intensity focal areas on contrast-enhanced T1-weighted images. All adults developed recurrences and/or metastases and died. Of the three children, two were living and free of disease at the end of the study and the third child died of chemotherapeutic-induced leukemia. Although imaging features of EMC are nonspecific, its chondroid-type calcifications and foci of low signal intensity within enhancing lobules may reflect its dual histopathologic morphologic characteristics of differentiated cartilage islands interspersed within vascular undifferentiated mesenchyme.

Adult↗
PubMed1992

High-dose busulfan and thiotepa with autologous bone marrow transplantation in childhood malignant brain tumors: a phase II study.

In order to evaluate the effect of intensive combined chemotherapy in pediatric brain tumors, we designed a phase II study of high-dose busulfan and thiotepa followed by bone marrow transplantation (BMT) in children with measurable recurrent brain tumors. As alkylating agents, busulfan and thiotepa were expected to exhibit a steep dose effect and no overlapping extramedullary toxicity. Moreover, both drugs have an excellent distribution into the central nervous system in humans. Since May 1988, 20 children (median age 6 years) have been treated. Busulfan (150 mg/m2/day x 4) given orally was followed by thiotepa (350 mg/m2/day x 3), given as a 1 h i.v. infusion. Cryopreserved bone marrow was reinfused 48 h after completion of chemotherapy. Tumor response was assessed by computed tomography and magnetic resonance imaging 4 to 6 weeks after BMT. Five partial responses were observed (three of six medulloblastomas, one of five ependymomas, one of two primitive neuroectodermal tumors); two patients with medulloblastoma and one with brain stem tumor achieved an objective response. Ten patients had stable disease and one progressive disease. One patient is not evaluable because of early toxic death. Toxicity was high in terms of aplasia and cutaneous, hepatic and neurological complications. The overall response rate of 26% is encouraging since all patients had disease refractory to all conventional therapies.

Adolescent↗
PubMed1991

Childhood malignant lymphoma of bone.

From 1974 to 1987, 450 children with non-Hodgkins' lymphoma (NHL) were seen at the Institut Gustave Roussy (IGR); 14 children had malignant lymphoma of bone (MLB). Eleven of the 14 were newly diagnosed, whereas three presented in relapse. Nine patients presented with multifocal bone involvement. The median age of these eight girls and six boys was 9.5 years (range 1.25-15 years). Bone pain was present in all patients as the initial symptom. Evaluation included physical examination, routine serum chemistries, complete blood count, chest roentgenography, skeletal survey, radionuclide bone scan, lumbar puncture, bone marrow aspiration, and intravenous pyelography, and/or abdominal ultrasonography. Hypercalcemia was found in six patients. Biopsy was performed in 12 patients, revealing high-grade lymphoblastic lymphomas in all. In two patients diagnosis was made on cytological examination of bone marrow aspirate. Immunophenotyping in four cases, demonstrated non-B, non-T cell origin in three and pre-B cell origin in one. Three patients were treated prior to 1982 with Cyclophosphamide/Oncovin/Prednisone/ADriamycin (COPAD) and seven patients, seen after 1982, were treated with a modified LSA2L2 protocol (LMT). None of the previously untreated patients received radiotherapy. All patients treated with COPAD have died, whereas four out of seven treated with LMT are alive with a median follow up of 51 months (range 36-82 months). One child treated on a pilot study died. One of the three children seen at relapse is disease-free with a follow-up of 98 months after high-dose chemotherapy followed by autologous bone marrow transplantation (ABMT). Five out of six patients presenting with hypercalcemia have died. Results with LMT are encouraging and together with published results suggest that sufficiently intensive chemotherapy can result in complete remission and cure in MLB. Radiotherapy does not seem to be necessary, avoiding possible serious long-term effects. Hypercalcemia is a bad prognostic feature.

Adolescent↗
PubMed1989

Limited small cell lung cancer treated by combined radiotherapy and chemotherapy: evaluation of a grading system of lung fibrosis.

A grading system of radiological fibrosis was defined and applied by four observers for the reading of 218 posterior-anterior chest X-rays of 78 patients. These patients with limited small cell lung cancer were treated from May 1980 to July 1983 in two consecutive alternating radiotherapy-chemotherapy schedules. Chest X-rays performed at each 6-month interval were read by each observer. A second reading was performed the day after. The analysis of results showed that in spite of some systematic variations in intra- and inter-observations, the proposed grading system had a good reproducibility. The radiological lung fibrosis score progressed between 6 and 12 months but was stable after one year of follow-up. There was no difference in the score of lung fibrosis between the two protocols which delivered a total dose of 45 and 55 Gy to the mediastinum. There was no significant correlation between the radiological changes and clinical symptoms.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1989

[Secondary metastatic neuromeningeal localization of neuroblastoma in children].

In order to evaluate the frequency, clinical and radiological aspects and prognosis of central nervous system metastases in children's neuroblastoma, the 258 children presenting with neuroblastoma, and registered from January 1982 to August 1987, were studied. Among them, 7 patients (2.7%), of which 6 had an initially metastatic neuroblastoma, presented with a secondary neuro-meningeal involvement. Parenchyma involvement (4 cases) occurred after a mean period of time of 21 months and marked the relapses. The disease recurs later on, even when locally controlled by surgical excision and local irradiation. Meningeal involvements (3 cases) occurred after a mean delay of 12.7 months, in patients with full tumoral evolutivity, and were responsible for rapid death. The clinical presentation of these metastases differs from that in adults by the rapidity of setting up of the signs and the frequency of intracranial hypertension. CT scan allows approaching diagnosis in the majority of the cases. These data are compared with those in the literature, where 30 cases were reported: they show a high patients' average age and the worse prognosis.

Brain Neoplasms↗
PubMed1988

The role of magnetic resonance imaging in the evaluation of Ewing sarcoma. A report of 27 cases.

The experience with magnetic resonance imaging (MRI) in 27 patients with Ewing sarcoma is reported and compared with computed tomography (CT) and plain films. Plain radiography proved to be the best imaging method to asses probable histological diagnosis in all cases (n = 6). For the evaluation of chemotherapeutic response (n = 4), CT and MRI gave the same information about the variation in size of the tumor. In this small series, the high signal in T2 weighted images was not altered significantly by therapy. In preoperative evaluation (n = 14), MRI gave better information than CT of soft tissue involvement and extension within the bone marrow in two cases each. The ability of MRI to accurately define extension through the epiphyseal plate in two cases permitted limb salvage which otherwise would not have been possible. In the long-term follow-up (n = 12), three patients without recurrence one year after therapy showed a low signal in the surgical area in T2 weighted images. Nine patients had a high signal in T2 weighted images: four were reactive lesions, two had obvious recurrence, and one was a hematoma. In the two remaining cases plain films and CT were normal, in the presence of both active tumor and reactive lesions. It was not possible with MRI to differentiate active tumor from reactive change, even after Gd-DTPA infusion.

Adolescent↗
PubMed1988

[Magnetic resonance imaging for bone marrow metastases of neuroblastoma].

From March 1985 to February 1987, 41 patients (pts) presenting with a neuroblastoma underwent 52 MRI to detect bone marrow metastases. Mean age was 4 years (R: 6 m, 13 y). Acquisitions were done with a 1.5 t unit. Images were obtained in coronal (legs and pelvis) and sagittal (dorso-lumbar spine) sections. Nine out of 52 examinations were excluded because of artifacts or technical failure. In 13 cases, MRI was performed for initial staging, in 30 during follow-up. Out of 24 anatomically proven medullary involvement (18 pts), MRI showed focal abnormal signals in 23 (17 pts): foci of hypersignal in T2 weighted images, compared to the normal value of bone marrow and fat tissue, were more often detected in lower limbs than dorso-lumbar vertebral body or iliac bone. In our series, the sensitivity of MRI to detect BM metastases is 84% and the specificity is 88%. In comparison to the medullograms and bone marrow biopsy, MRI explores distinct sites, especially lower limbs which are often involved.

Bone Marrow↗
PubMed1988

Bone marrow metastases in children's neuroblastoma studied by magnetic resonance imaging.

Forty-one patients (pts) presenting with a neuroblastoma underwent 52 MRI to detect bone marrow metastases. Mean age was 4 years. Acquisitions were done with a 1.5 tesla unit. T1 and T2 weighted images were obtained in coronal (legs and pelvis) and sagittal (dorso-lumbar spine) sections. In 13 cases MRI was performed for initial staging, in 30 during the follow-up. 43/52 examinations were evaluable. Out of 24 anatomically proven medullary involvement (19 pts), MRI showed focal abnormal signals in 23 (18 pts): foci hypersignal in T2 weighted images and hyposignal in T1 weighted images compared to the normal bone marrow (BM) and fat tissue. The lesions were more often detected in lower limbs than dorso-lumbar vertebral body or iliac bone. Nineteen examinations were performed in 15 pts with cytologically and histologically normal BM. MRI raised suspicion of BM metastases in 5 pts (7 MRI). Out of those 5 pts, 1 (2 MRI) had BM relapse 9 months later; 1 (2 MRI) had intra cranial relapse 6 months later; 1 (1 MRI) is disease free 1 1/2 year later; the follow-up is too short for 2 remaining pts (2 MRI). MRI's specificity was 88.9% and sensitivity 84.4%.

Adolescent↗