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F Doz

Publications and source records attributed to F Doz.

At least 73 records · Page 4Linked to original sources
PubMed1997

Subdural sarcoma associated with chronic subdural hematoma. Report of two cases and review of the literature.

The authors report the cases of two children who presented in the first months of life with progressive macrocrania related to chronic pericerebral fluid collection. This condition resolved spontaneously without treatment after a few months in the first case, whereas it required several aspirations of blood-stained fluid via the fontanel in the second case. Both patients developed normally without evidence of disease in the earliest years of life and presented at the ages of 3 1/2 and 4 1/2 years, respectively, with symptoms and signs of rapidly progressing intracranial hypertension. In both cases contrast-enhanced computerized tomography and magnetic resonance imaging revealed masses in the subdural space of the skull base and the cranial vault associated with significant subdural fluid collections. In the first case the lesion was misdiagnosed in the initial phase and treated, by means of multiple craniotomies, as an organized subdural hematoma. After a diagnosis of liposarcoma had been made, the patient was treated with chemotherapy, which resulted in a good resolution of the lesions at 3-month follow-up review. In the second case a biopsy allowed the diagnosis of fibrohistiocytic sarcoma and the patient was treated with chemotherapy. The authors review the literature of the few reported cases and discuss the possible pathophysiological association between pericerebral fluid collection and the subsequent development of a subdural sarcoma.

Biopsy↗
PubMed1997

[High-dose chemotherapy in relapse of medulloblastoma in young children].

Craniospinal irradiation is the gold standard treatment used in non metastatic medulloblastoma as prophylaxis against central nervous system (CNS) metastases. However, given the severe late effects caused by this procedure in children under 3 years of age, most pediatric oncologists are currently treating these patients with conventional chemotherapy in order to postpone or even avoid irradiation. In the French Society of Pediatric Oncology (SFOP) this attitude has been adopted since 1990. Among the patients treated without radiotherapy, 20 relapsed while on conventional chemotherapy and were entered in a study of high-dose chemotherapy (HDC) followed by autologous bone marrow transplantation (ABMT). Their median age at diagnosis was 23 months (range: 5-71 months) and the relapse occurred at a median time of 6.3 months after the initiation of chemotherapy. Complete surgical removal of the local relapse was the first treatment in 4/20 patients who were not evaluable for response. Sixteen of the 20 patients had measurable disease at the primary site (9 patients), or at metastatic sites (3 patients) or both (4 patients). The conditioning regimen consisted of combination busulfan 600 mg/m2 over 4 days and thiotepa 900 mg/m2 over 3 days. After recovery from aplasia, patients with a local relapse received local radiotherapy limited to posterior fossa. Among the 16 patients with measurable disease, 6 complete responses, 6 partial responses, 3 non response, were observed following HDC (response rate 75%). One patient was not evaluable. For the 20 patients, the event free survival (EFS) is 50%. Among the surviving patients, the median follow-up is 39.5 months post BMT (range: 21-92 months). Ten patients who developed a local relapse or local progression are alive with non evidence of disease (NED) without craniospinal irradiation. Among the 7 patients who developed a metastases or progression of metastases, only 1 is alive. Toxicity was high but manageable. One complication-related death occurred 1 month post BMT. With a 75% response rate, this HDC proved to be very efficient in relapsed medulloblastoma. A longer follow-up is necessary to demonstrate whether, after a local relapse, HDC could replace craniospinal irradiation as prophylaxis against CNS metastases.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1996

Will high dose chemotherapy followed by autologous bone marrow transplantation supplant cranio-spinal irradiation in young children treated for medulloblastoma?

UNLABELLED: Cranio-spinal irradiation is the gold standard treatment used in non metastatic medulloblastoma as prophylaxis against central nervous system (CNS) metastases. However, given the severe late effects caused by this procedure in children under 3 years of age, most pediatric oncologists are currently treating these patients with conventional chemotherapy in order to postpone or even avoid irradiation. In the French Society of Pediatric Oncology (SFOP) this attitude has been adopted since 1987. Among the patients treated without radiotherapy, 20 relapsed while on conventional chemotherapy and were entered in a study of high-dose chemotherapy (HDC) followed by ABMT. Their median age at diagnosis was 23 months (R5-71) and the relapse occurred at a median time of 6.3 months after the initiation of chemotherapy. Complete surgical removal of the local relapse was the first treatment in 4/20 patients who were not evaluable for response. Sixteen of the twenty patients had measurable disease at the primary site (9 patients), or at metastatic sites (3 patients) or both (4 patients). The conditioning regimen consisted of combination Busulfan 600 mg/m2 over 4 days and Thiotepa 900 mg/m2 over three days. After recovery from aplasia, patients with a local relapse received local radiotherapy limited to posterior fossa. RESULTS: among the 16 patients with measurable disease, 6 CR, 6 PR, 3 NR, were observed following HDC (response rate 75%). One patient was not evaluable. For the 20 patients, the EFS is 50%. Among the surviving patients, the median follow up is 31 months post BMT (R12-82). Ten patients who developed a local relapse or local progression are alive with NED without craniospinal irradiation. Among the 7 patients who developed metastases or progression of metastases, only one is alive. Toxicity was high but manageable: the median duration of granulocytopenia < 0.5 x 109/l and thrombocytopenia < 50 x 10(9)/l was 13 and 41 days respectively. Bacteremia was documented in 4 cases. Grade > 2 mucositis and diarrhea were observed in 60% of patients. One complication-related death occurred 1 month post BMT. CONCLUSION: With a 75% response rate, this HDC proved to be very efficient in relapsed medulloblastoma. A longer follow up is necessary to demonstrate whether, after a local relapse, HDC could replace craniospinal irradiation as prophylaxis against CNS metastases.

Antineoplastic Agents↗
PubMed1996

[Pulse oximetry and methemoglobinemia].

BACKGROUND: Cyanosis associated to low oxygen saturation may reveal hemoglobin pathology. CASE REPORT: A 3 year-old child had a nephroblastoma with pleural effusion. He suddenly developed persistent cyanosis despite pleural effusion drainage; transcutaneous and measured oxygen saturations were low and PaO2 on arterial blood gases was high. Methemoglobinemia was diagnosed, due to prilocaine-lignocaine cream used for local anesthesia, associated to partial G6PD deficiency. The methemoglobinemia disappeared after methylene blue treatment. CONCLUSION: Cyanosis with low oxygen saturation and high or normal PaO2 should lead to the search of a hemoglobin pathology, especially methemoglobinemia, by appropriate methods.

Anesthetics, Local↗
PubMed1996

N-MYC amplification, loss of heterozygosity on the short arm of chromosome 1 and DNA ploidy in retinoblastoma.

Recurrent genetic alterations different from the alteration of the RB1 gene on chromosome 13q14 have been described in retinoblastoma, including structural alterations on the short arm of chromosome 1 and amplification of the N-MYC oncogene. These two genetic alterations are major prognostic factors in neuroblastoma, another embryonic neuro-ectodermal tumour. In order to assess the frequency of these alterations and their possible association with clinical parameters in retinoblastoma, we studied a series of 46 retinoblastoma tumour samples. Ploidy was assessed by flow cytometry, N-MYC copy number was evaluated by a spot-blot procedure using the pNb-1 probe and loss of heterozygosity was investigated by PCR analysis at mini- and microsatellites located on the short arm of chromosome 1. Most tumours were in the diploid or near diploid range; only one case exhibited tetraploidy. N-MYC amplification was observed in only one of the 45 tumours. Loss of heterozygosity on the short arm of chromosome 1 was observed in 9/43 tumours (21%); in particular, its incidence was higher in metastatic than in localised disease (P < 0.05). We suggest that alterations of one or several genes on chromosome 1p might play a role in the oncogenesis or progression of retinoblastoma. Analysis of the long term follow-up of these and additional patients should determine the prognostic value of this parameter.

Child, Preschool↗
PubMed1996

A high-dose busulfan-thiotepa combination followed by autologous bone marrow transplantation in childhood recurrent ependymoma. A phase-II study.

Sixteen children with refractory or relapsed ependymoma were entered in a phase-II study of high-dose chemotherapy followed by autologous bone marrow transplantation (ABMT). The conditioning regimen consisted of busulfan 150 mg/m2/day for 4 days and thiotepa 300 mg/m2/day for the 3 following days. All patients had previously been treated by surgery and conventional chemotherapy. Eight of them had also received irradiation at doses ranging from 45 to 55 Gy at the tumor site. At the time of transplantation, 9 patients were in first relapse, 5 in second relapse and 2 in third relapse or more; all had measurable disease; 15 patients were evaluable for response. No radiologic response > 50% was observed. Stable disease and progressive disease were documented in 10 and 5 cases, respectively. The duration of response to this treatment, which lasted for a median time of 7 months (range: 5-8 months), was only evaluable in 5 patients who did not receive further treatment after ABMT. To date, there are 3 disease-free survivors at 15, 25 and 27 months all of whom were treated with second complete surgical resection and local radiotherapy (55 Gy). Toxicity was severe, mainly digestive and cutaneous, and 1 toxicity-related death occurred. Unlike medulloblastomas, ependymomas do not appear to be sensitive to this combination therapy. New therapeutic approaches are warranted.

Adolescent↗
PubMed1995

Spectrum of germline mutations in the RB1 gene: a study of 232 patients with hereditary and non hereditary retinoblastoma.

Germline mutations in the RB1 gene confer hereditary predisposition to retinoblastoma. We have performed a mutation survey of the RB1 gene in 232 patients with hereditary or non hereditary retinoblastoma. We systematically explored all 27 exons and flanking sequences as well as the promotor. All types of point mutations are represented and are found unequally distributed along the RB1 gene sequence. In the population we studied, exons 3, 8, 18 and 19 are preferentially altered. The range of frequency of detection of germline mutations is about 20%, indicating that other mechanisms of inactivation of RB1 should be involved. The spectrum of mutations presented here should help to improve the clinical management of retinoblastoma and to understand the molecular mechanisms leading to tumorigenesis.

Base Sequence↗
PubMed1995

Etoposide and carboplatin in extraocular retinoblastoma: a study by the Société Française d'Oncologie Pédiatrique.

PURPOSE: A phase II study of etoposide (VP-16) and carboplatin was performed in patients with extraocular retinoblastoma to evaluate the response rate with this drug combination. PATIENTS AND METHODS: Twenty patients with extraocular retinoblastoma, age 9 to 120 months, were included in a cooperative multicenter phase II study of the Société Francçaise d'Oncologie Pédiatrique (SFOP). The schedule consisted of consecutive 5-day treatment with VP-16 100 mg/m2/d and carboplatin 160 mg/m2/d. RESULTS: The response rate for the 20 patients was 85%; there were nine complete responses and eight partial responses. Hematologic toxicity was the only serious observed toxicity and was always manageable. CONCLUSION: This combination of VP-16 and carboplatin is highly effective in extraocular retinoblastoma. The high response rate is encouraging for further evaluation of this drug combination in adjuvant chemotherapy when necessary after enucleation or in neoadjuvant chemotherapy for intraocular tumors.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1995

Preirradiation chemotherapy including "eight drugs in 1 day" regimen and high-dose methotrexate in childhood medulloblastoma: results of the M7 French Cooperative Study.

The aim of this study was to evaluate the feasibility and efficacy of a protocol that includes "sandwich" chemotherapy, that is, chemotherapy alternated with radiotherapy, and reduced doses of supratentorial irradiation in children with medulloblastoma. Between March 1985 and September 1988, 70 successive children with newly diagnosed medulloblastoma from eight centers were treated in this prospective nonrandomized study. Patients were assigned to two risk groups. Group A included patients with macroscopically complete or subtotal excision, no brainstem involvement, no atypical cells in the cerebrospinal fluid, normal myelography, and who were more than 2 years of age. Group B patients encompassed those who did not fit the criteria for Group A. Two children were excluded from analysis after histological review confirmed ependymoma. Thus, a population of 68 children was selected, with 31 in Group A and 37 in Group B. Treatment consisted of two courses of the "eight drugs in 1 day" ("8/1") regimen followed by two courses of high-dose methotrexate (12 g/m2). Radiotherapy was begun during the 7th week after surgery in Group A and during the 5th week in Group B. In patients older than 2 years, the median radiation dose to the posterior fossa, the spinal axis, and the brain was 54 Gy, 36 Gy, and 27 Gy, respectively. Group B patients received postirradiation chemotherapy with four 8/1 courses monthly. The median time from surgery to radiation therapy was 50 days (range 21 to 141 days). One fatality due to chicken pox on Day 102 and one World Health Organization Grade IV infection occurred. The estimated 5- and 7-year disease-free survival (DFS) rates were 62% and 59%, respectively. These were 74% and 62% in Group A and 57% and 57% in Group B. Patient age, extent of resection, and radiation dose to the whole brain had no prognostic value. Patients with metastasis had a nonsignificant trend for a worse prognosis than patients with nonmetastatic disease (7-year DFS 45% vs. 68%, p = 0.11). In Group B, the 7-year DFS rates for children who received more or less than 30 Gy to the brain were 69% and 52% respectively (p = 0.15). There were recurrences in the posterior fossa (37%), spine (20%), and brain (20%). After a review of radiotherapeutic treatments, only one supratentorial failure could be blamed on reduction of the supratentorial radiation dose. This "sandwich" chemotherapy appeared to be feasible and did not show adverse survival data when compared to other series.

Adolescent↗
PubMed1994

The role of chemotherapy in orbital involvement of retinoblastoma. The experience of a single institution with 33 patients.

BACKGROUND: Orbital involvement is a rare occurrence in retinoblastoma but still carries a bad prognosis. The aim of this study was to define more clearly the role of chemotherapy in this advanced disease. METHODS: Between 1977 and 1991, 33 patients were treated at the Services de Pédiatrie at Institut Curie (Paris, France) for orbital involvement of retinoblastoma, which was isolated in 20 patients and associated with metastases in 13 patients (outside the central nervous system [CNS], 6; within the CNS, 7). Treatment included chemotherapy for 33 patients, irradiation of the orbit for 23 patients, and intrathecal chemotherapy and/or CNS irradiation in selected patients. RESULTS: The plateau phase of the survival curve was reached at 15 months, with a survival of 34% plus or minus 8%. The disease free interval was longer when patients had no CNS disease (P < 0.05). Twenty of the 21 recurrences (95%) occurred within 1 year after diagnosis of orbital involvement. CONCLUSIONS: Intensive chemotherapy using cyclophosphamide, platinum compounds, epipodophyllotoxins, doxorubicin, and vincristine was effective in orbital involvement of retinoblastoma even with associated extra-CNS metastases. However, associated CNS disease still carries a bad prognosis, and long term follow-up is necessary to evaluate the risk of a second tumor.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

Carboplatin and VP 16 in medulloblastoma: a phase II Study of the French Society of Pediatric Oncology (SFOP).

The purpose of this study is to evaluate the antitumor activity of combination carboplatin and etoposide in measurable medulloblastoma. From January '89 to January '92, 26 patients with medulloblastoma were included in a multicentric phase II study of 2 courses of carboplatin 160 mg/m2/d day 1 to day 5 and VP16 100 mg/m2/d day 1 to day 5. Median age was 10 years (19 months-14.5 years). First treatment was surgery alone in 1 patient, surgery + radiotherapy in 4 patients, surgery + chemotherapy in 2 patients less than 3 years old, surgery + radiotherapy + chemotherapy in 19 patients ("8 drugs in 1 day" based:17, SIOP I:1, SIOP II:1). Previous treatment included cisplatin (20 cases), carboplatin (1 case), and VP16 (7 cases). Measurable disease was evaluated by CT scan, MRI or myelogram and CSF. Response rate (RR) was 72 +/- 10%:8 complete responses (CR), 10 partial responses (PR), 1 objective effect (OE), 6 progressive disease (PD), 1 non-evaluable. Thirty-six courses were evaluated for toxicity. Median duration of WHO grade 4 neutropenia was 8 days (0-23). One patient died at day 18 after the first course because of diffuse haemorrhage during septic aplasia. Five other non-life-threatening septicemias were recorded. Median number of platelet transfusions was 1 (0-4). One child who had achieved a PR after two courses died from CNS bleeding after the third course. This drug combination achieves a high response rate in childhood medulloblastoma. Severe toxicity has been mainly encountered in previously heavily treated patients. Tolerance may be acceptable in newly diagnosed children, but careful hematological follow-up and platelet transfusional support are definitely mandatory.

Adolescent↗
PubMed1994

Effect of pharmacologic doses of zinc on the therapeutic index of brain tumor chemotherapy with carmustine.

To evaluate the potential differential effect of pretreatment with pharmacologic doses of the trace element zinc on the chemosensitivity of glioma cells and bone marrow cells for carmustine (BCNU), we performed in vitro and in vivo studies of zinc toxicity as well as of the combined treatment with zinc and the anticancer drug. We studied the in vitro effects on established human and rat glioma cell lines using a microcolorimetric growth assay and on murine bone marrow using a clonogenic assay for committed progenitor cells of the granulocyte-monocyte lineage. Zinc exposures of up to 100 microM for 120 h did not influence the growth of six of seven human glioma cell lines. Only U87MG demonstrated statistically significant toxicity during high zinc exposure (100 microM over 120 h). Dose-response growth curves generated for BCNU did not show protection against the anticancer agents by a 48-h pretreatment with different zinc concentrations. The clonogenic capacity of bone marrow cells was slightly reduced by in vitro culture for 24 and 48 h. Although this effect appeared to be more prominent in the presence of zinc supplementation, overall a statistically significant inhibition was seen only after exposure to a concentration of 100 microM zinc over 48 h. As compared with chemotherapy alone, in vitro pretreatment with 50 microM zinc over 48 h followed by chemotherapy resulted in an increased number of colony-forming unit-granulocyte monocyte (CFU-GM): CFU-GM increased by a factor of 2 for BCNU (60 microM x 2 h). This statistically significant in vitro chemoprotection would translate into a dose-protection factor of 1.5, i.e., for the same level of myelosuppression, zinc pretreatment would allow administration of a 50% increased dose of BCNU. The in vivo studies were performed in an s.c. xenograft model of the human glioma cell line U87MG in athymic mice. The maximal tolerable pretreatment with zinc was determined to be a 10-day course of daily i.p. injections of 10 mg/kg ZnCl2. The subsequent i.p. administration of the dose lethal to 10% of the mice (LD10) and of a 1.5 x LD10 dose of BCNU resulted in less bone marrow toxicity in pretreated animals than in non-zinc-pretreated mice as determined in a CFU-GM assay. Glioma colony-forming efficiency (CFE) assays, on the other hand, did not show any zinc-related difference in the BCNU sensitivity of U87MG.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1994

A phase II study of intravenous carboplatin for the treatment of recurrent gliomas.

Thirty-two patients with recurrent glioma who had previously received radiation therapy and chemotherapy with nitrosoureas were treated with intravenous carboplatin every 3 weeks, starting at a dose of 350 mg/m2, with a dose escalation of 25 mg/m2 every 6 weeks until a level 4 hematologic toxicity was reached. Of the 28 patients who could be evaluated for a response, 50% demonstrated a response or had stabilization of their disease after two infusions of carboplatin. Their median time to tumor progression and median duration of survival were 19 weeks and 38 weeks. Thrombocytopenia was the major toxicity and was severe in one-third of the patients. No neurologic or renal toxicities were noted. Carboplatin has demonstrated activity against recurrent gliomas in patients who have already had extensive chemotherapy. Increasing the dose of carboplatin may improve the rate of response and the duration of progression-free survival in patients with recurrent glioma.

Adult↗
PubMed1994

Metastatic medulloblastoma: the experience of the French Cooperative M7 Group.

A retrospective analysis was performed to determine the outcome of children with metastatic medulloblastoma given a standardised treatment programme. Of 68 consecutive patients treated in the French M7 protocol for medulloblastoma, 23 presented with metastatic disease. They were uniformly treated with surgery, and the same protocol of chemotherapy and craniospinal radiotherapy. The 7-year relapse-free survival rate is 43% for metastatic patients compared to 68% for patients with localised disease. Survival did not correlate with age, sex, location of metastases, extent of initial surgery and the dose of radiation therapy on the posterior fossa. Survival did correlate with the dose to the cranial field with a threshold dose of 30 Gy. Patients with metastatic disease have a worse prognosis and require more aggressive therapies at initial presentation. The prognostic impact of the different sites of metastatic disease requires further evaluation in cooperative studies.

Adolescent↗
PubMed1993

[Malignant cerebral tumors in children].

Malignant brain tumours (mainly medulloblastoma, glioma, and ependymoma) are the first cause of solid tumours in children, and a major cause of mortality from cancer in paediatrics. The most frequent circumstance of discovery is intracranial hypertension. Early and atypical signs should give the alarm and call for emergency neuroradiological explorations. Major therapeutic advances have been made in the last ten years in the fields of neurosurgery, radiotherapy and chemotherapy of brain tumours in children. Multidisciplinary care is now indispensable usually as part of multicentre cooperative clinical trials. Therapeutic approaches are guided by a concern not only for effectiveness, but also for low toxicity, in order to reduce the long-term sequelae often caused by irradiation of the developing central nervous system.

Brain Neoplasms↗
PubMed1993

Metallothionein and anticancer agents: the role of metallothionein in cancer chemotherapy.

Metallothioneins (MTs) are intracellular proteins containing the highest amount of thiol groups within the cytoplasm. These thiol groups are able to bind several cytotoxic agents, such as platinum compounds and alkylating agents. Increased levels of MT are one mechanism of resistance to these anticancer drugs, as intracytoplasmic binding of MT prevents the active molecules from reaching their target, the intranuclear DNA of tumor cells. MT synthesis can easily be induced by physiologic heavy metals such as zinc and copper. Pharmacological modulation of MT levels has been used to increase the MT pool in normal tissues and decrease their susceptibility to the toxicity of anticancer drugs. In the case of tumors arising in the brain, where the inducibility of MT synthesis is low, this approach would allow protection of normal tissues without decreasing the antitumor activity of the cytotoxic agents. The interaction of MT with cytotoxic agents is not limited to covalent binding. A correlation between MT synthesis and amplification of oncogenes such as ras has been reported. Furthermore, the cytotoxic drugs are bound by MT after competition with zinc and copper; these metals are cofactors of numerous metalloenzymes, some of which are involved in the metabolism of nucleic acids. Competitive displacement of these metals might modify nucleic acid metabolism and influence cellular proliferation. On the other hand, increased MT levels could provide a zinc cofactor reserve that increases the cell's reparative potential when faced by DNA damage by cytotoxic agents.(ABSTRACT TRUNCATED AT 250 WORDS)

Alkylating Agents↗