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F Chauvin

Publications and source records attributed to F Chauvin.

At least 55 records · Page 3Linked to original sources
PubMed1995

[Cancers in children in the Auvergne area: retrospective study from 1986 to 1991].

BACKGROUND: The specificity of childhood cancers led to the creation of regional childhood cancer registries. An epidemiological study of childhood cancers in the Auvergne area was carried out over a 6 year-period (1986-1991) in order to create a registry. POPULATION AND METHODS: The population of our study was 252,820 children (0-15 years old), living in the Auvergne region. All malignant neoplasms were included together with brain tumours (whatever grading). Data were collected from medical and administrative sources. RESULTS: The data of 153 cases were collected during this period. World age standardized overall incidence rate was 120.5 cases/milion/year. Age standardized incidence rates were: leukemias 37.6 (ALL 28.01), central nervous system tumours 18.34 (medulloblastomas 4.6, astrocytomas 4.6, ependymomas 3.8), lymphomas 10.0, neuroblastomas 18.6, soft tissue tumors 8.3, bone tumours 6.1 (Ewing's sarcomas 4.1, osteosarcomas 2.0), nephroblastomas 5.5, retinoblastomas 3.1, liver tumours 0.5 and others 0.5. CONCLUSIONS: Our data base in the Auvergne area might be a source of information for epidemiological studies on the role of etiological factors, the survival, the sequelae and the incidence trends.

Adolescent↗
PubMed1995

Evaluation of the informed consent procedure in cancer patients candidate to immunotherapy.

By addressing questionnaires to 24 cancer patients candidate to immunotherapy, we evaluated both the effects and the effectiveness of the medical information provided to the patient on their knowledge of the disease and the treatment. Most patients had correctly understood the information but 69% stated that they had been unable to ask all the questions they wished, and 62% required additional information. Most patients admitted to being emotionally distressed throughout the interview. These results are not significantly different from those obtained in patients candidate to new chemotherapy agents, but show that important improvements in the informed consent procedure are required.

Attitude to Health↗
PubMed1994

Sugar transport by the bacterial phosphotransferase system. Characterization of the Escherichia coli enzyme I monomer/dimer equilibrium by fluorescence anisotropy.

Enzyme I (EI), the first protein of the bacterial phosphotransferase system (PTS), exists in a monomer/dimer (M/D) equilibrium. We have proposed that the two species are functionally different and that their interconversion may regulate sugar transport via the PTS. The C-terminal Cys of Escherichia coli EI was reacted with pyrene maleimide (Han, M. K., Roseman, S., and Brand, L. (1990) J. Biol. Chem. 265, 1985-1995), and the pyrene conjugate used to characterize the M/D equilibrium by fluorescence anisotropy. The properties of unlabeled and pyrene-labeled EI are indistinguishable. Values for the apparent association constant, K'eq, and the steady-state anisotropy of the monomer and the dimer were obtained under a variety of conditions. K'eq increases 23-fold, from 0.45 x 10(5) to 10.7 x 10(5) M-1, as the temperature increases from 6 to 30 degrees C; the association appears to be entropically driven. Under all conditions tested, the K'eq for phospho-EI is 6-12-fold less than for dephospho-EI. For phospho-EI, PEP and Mg2+ induce a 240-fold increase of K'eq when both ligands are present. Based on these data, EI was preincubated under conditions that change K'eq, and the initial activities of the different species were determined at 37 degrees C in a PTS sugar phosphorylation assay with PEP as the phosphoryl donor. The initial rate depends on the M/D ratio; it is maximal when EI is 100% dimer, and zero when EI is 100% monomer. In the latter case, the rate gradually increases in the assay mixture. The results have important implications for how the PTS regulates sugar transport and other physiological phenomena.

Biological Transport↗
PubMed1994

Sugar transport by the bacterial phosphotransferase system. Characterization of the Escherichia coli enzyme I monomer/dimer transition kinetics by fluorescence anisotropy.

Enzyme I of the bacterial phosphoenolpyruvate: glycose phosphotransferase system (PTS) exists in a monomer/dimer (M/D) equilibrium. These two forms are functionally different, and their interconversion may be a means of regulating the PTS. The M/D equilibrium was studied by fluorescence anisotropy of a pyrene derivative (Chauvin, F., Brand, L., and Roseman, S. (1994) J. Biol. Chem. 269, 20263-20269). In this paper, the kinetics of the transition is investigated. The following apparent rate constants were found for the M/D transition of phospho-Enzyme I in the presence of Mg2+ and PEP at 6 degrees C: k*A = 3.4 x 10(3) M-1 s-1 and k*D = 1.04 x 10(3) s-1. The association rate is especially slow, 2-3 orders of magnitude slower than the average dimerization rate determined for other proteins. Furthermore, the rate of quaternary structure changes matches that of enzymatic activity changes, as well as that of tertiary structure changes (Chauvin, F., Toptygin, D., Roseman, S., and Brand, L. (1992) Biophys. Chem. 44, 163-173). Finally, the effect of two ligands is shown; PEP increases the relaxation rate by 3-fold at 23 degrees C, and Mg2+ addition causes a 4-fold increase in the relaxation rate.

Biological Transport↗
PubMed1994

Autologous bone marrow transplantation for pediatric Wilms' tumor: the experience of the European Bone Marrow Transplantation Solid Tumor Registry.

This survey includes 25 children with Wilms' tumor undergoing high-dose chemotherapy associated with autologous bone marrow transplantation (ABMT) in the period June 1984-December 1991 and enrolled in the European Bone Marrow Transplantation Registry for Solid Tumors. At diagnosis, 12 children presented stage IV disease, 5 stage III, 3 stage II, and 5 stage I. Before ABMT, 21 children had 1 to 4 relapses (median 1); 13 achieved a second or subsequent complete remission (CR), four stage IV children failed to respond to first line treatment and achieved either CR (3 patients), or partial remission (PR) after second line therapy. At high-dose chemotherapy, 17 children were in CR and 8 had measurable disease. Seven different high-dose regimens were administered, even if 20 children received melphalan mostly associated with vincristine and 8 involved field radiotherapy. Three children died early of pneumonitis; 2 developed an acute transient renal failure, 1 a chronic renal failure. Out of the 8 children with target disease at graft, 2 died of toxicity, 5 achieved CR, 1 obtained PR, and only 1 is presently alive in CCR at 39 months after ABMT. Of the 17 children grafted in CR, 8 are alive event-free at 14-90 months (median 34) from ABMT; 7 relapsed at 3-23 months (median 7 months); 1 died of toxicity and 1 was lost to follow-up in CR at 12 months. A salvage attempt with high-dose chemotherapy in children with resistant or poor prognosis recurrent Wilms' tumor seems to be justified. An international cooperative protocol taking into account the increased risk of lung and renal toxicity is necessary.

Adolescent↗
PubMed1994

FAC (fluorouracil, doxorubicin, cyclophosphamide) as second line chemotherapy in patients with metastatic breast cancer progressing under FEC (fluorouracil, epirubicin, cyclophosphamide) chemotherapy.

BACKGROUND: The cross-over resistance between different anthracyclines in breast carcinoma has not been largely evaluated in clinical trials. PATIENTS AND METHODS: Nineteen patients with metastatic breast cancer who had failed prior first line FEC chemotherapy (fluorouracil 500 mg/m2, epirubicin 50 mg/m2 cyclophosphamide 500 mg/m2, every 4 weeks) were treated with a combination of fluorouracil 500 mg/m2, doxorubicin 50 mg/m2 and cyclophosphamide 500 mg/m2 every 4 weeks (FAC). RESULTS: Five patients achieved partial responses, ranging in duration from 5 to 8 months. The main toxicity was cardiac, with congestive heart failure documented in five patients. CONCLUSION: The findings indicate an absence of cross resistance of doxorubicin in some epirubicin-resistant patients.

Adult↗
PubMed1994

Comparison of auto versus allografting as consolidation of primary treatments in advanced neuroblastoma over one year of age at diagnosis: report from the European Group for Bone Marrow Transplantation.

A case control study was performed to investigate the potential advantage of allogeneic bone marrow transplantation in advanced or poorly responding neuroblastoma first remission patients using the European BMT Solid Tumor Registry. Seventeen allogeneic and 34 autologous bone marrow transplantation (BMT) cases were matched based on a number of prognostic factors including age, sex, prior treatment duration, pre-graft response status and bone and BM involvement before BMT. Only single BMT procedures are included. The median age at diagnosis was 47 months (range 18-113 months). The median follow-up time since BMT is 58 months (range 13-133 months). The only significant prognostic factor within the allogeneic BMT (p = 0.012) and autologous BMT groups (p = 0.025) was residual skeletal disease before BMT, detected by mIBG in 86% of the cases. However, the progression-free survival was not significantly different: 35% and 41% at 2 years, respectively. Only half of the allogeneic BMT patients had developed graft-versus-host disease (GVHD): 7 of 9 grade I-II and only 2 of 9 grade IV. The median donor age was very young with 74 months (range 20-240 months) and 10 of 17 were sex matched. Thus absence of GVHD risk factors in young children could be the major obstacle in achieving an anti-tumor effect with allogeneic BMT in neuroblastoma.

Bone Marrow Transplantation↗
PubMed1994

[Economic evaluation of screening for neuroblastoma].

Though neuroblastoma, a cancer occurring in children, is infrequent, several countries run screening programs to detect it early since advanced stages show high mortality rates. The aim of this study is to propose a non empirical medico-economic evaluation model for the screening program for neuroblastoma, adaptable to various contexts. A marginal cost-effectiveness analysis was performed. The effectiveness and cost criteria were respectively the number of children who do not die from neuroblastoma and the cost of the screening programs, together with the cost of the treatments. The major parameters of the model were: size of target population, incidence, over-incidence rate, compliance rate, test sensitivity, distribution of cases and mortality rates according to the stage of the disease. The aim of the model was to determine, within a specific context (fixed parameters), the cost of an additional life saved, or less pragmatically to calculate the threshold values for the parameters for which the screening program for neuroblastoma is worthwhile (ie marginal cost equal to zero). We illustrate this model presentation with simulations elaborated from the neuroblastoma screening program performed in the Rhône area, France.

Child, Preschool↗
PubMed1993

Polychemotherapy in advanced non small cell lung cancer: a meta-analysis.

We did a meta-analysis of all published polychemotherapy vs supportive care clinical trials in patients with non-resectable non small cell lung cancer. 7 studies with more than 700 patients were selected. We used the number of deaths at 3, 6, 9, 12, and 18 months as the endpoints because we were unable to obtain all the individual data. Our analysis showed a reduction in mortality during the first 6 months with polychemotherapy. Although small, this increase in survival, together with an improved quality of life, suggests that polychemotherapy should be recommended for patients with non-resectable non small cell lung cancer.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1993

Phase II study of fotemustine as second-line treatment after failure of immunotherapy in metastatic renal cell carcinoma.

Sixteen patients who after prior systemic immunotherapy had progressing disease received fotemustine (100 mg/m2) i.v. on days 1, 8, and 15 followed by a 5-week rest period. In responding or stabilized patients, maintenance therapy consisted of 100 mg/m2 fotemustine given once every 3 weeks until progression on toxicity occurred. No objective response was observed. Four patients showed stable disease (median duration: 4 months; range: 3-19). The main toxicities were neutropenia (WHO grade 3 and 4: 27%) and thrombocytopenia (WHO grade 3 and 4: 27%). Fotemustine was administered on an outpatient basis and was generally well tolerated, but in our series of patients it had no antitumour activity in metastatic renal cell carcinoma after failure of immunotherapy.

Adult↗
PubMed1993

Limited disease small cell lung cancer: alternating combination of doxorubicin, etoposide, ifosfamide and hyperfractionated radiotherapy. Final results of a multicentric pilot study for the Groupe Lyonnias d'Oncologie Thoracique (GLOT).

In order to evaluate the effect on prolonging survival of alternating chemotherapy and radiotherapy schedules in patients with limited disease small cell lung cancer, 89 patients were included in a multi-institutional pilot study between January 1986 and May 1989. Treatment consisted of induction chemotherapy using the combination of doxorubicin, etoposide and ifosfamide (AVI) for four consecutive courses, followed by two cycles of the VI chemotherapy alternating with three hyperfractionated radiotherapy courses and then followed by two additional courses of AVI. Objective response to the four cycles of AVI combination was observed in 65 patients (75%). Thirteen out of 30 patients (44%) who were in partial response (PR) after induction chemotherapy were converted into complete response (CR) after the three alternating courses of chemotherapy and radiotherapy. The principal side effect related to combined modality treatment was acute radiation pneumonitis (21.5% cases) reversible except one which resulted in toxic death, and a second with chronic lung fibrosis with permanent WHO Grade 2 dyspnea (14%). Local relapse was observed in 47% of the patients who were considered in CR at the end of the treatment program and cerebral metastases were the first site of detectable relapse in 25% cases. The 3-year actuarial disease-free survival of the 89 patients is 5%, and the median actuarial survival is 14 months. This study shows that the promising survival rates seen in our previously published interim analysis were not maintained. Reasons for this might include the choice of a non cisplatinum containing induction chemotherapy, the late introduction of thoracic irradiation and/or to the use of non-restrictive criteria for selecting patients.

Adult↗
PubMed1993

High-dose chemotherapy with autologous bone marrow rescue in advanced stage IV neuroblastoma.

In order to better evaluate the role of bone marrow purging procedures in the treatment of stage IV neuroblastoma, two similar groups of patients, prospectively treated during the same period at Léon Bérard Center, Lyon, France, and at Giannina Gaslini Institute, Genova, Italy, were reviewed. 18 children were treated in Lyon with a protocol including induction chemotherapy, surgery and a single course of high-dose chemotherapy followed by purged autologous bone marrow rescue. 21 patients were treated in Genoa with a very similar protocol which did not include purging procedures. Progression-free survival at 6 years was 12% (95% confidence interval 0-24%), without any difference between the two series of patients. The only prognostic factor for long-term survival was the persistence (or not) of bone lesions and the presence of metastatic disease (bone or bone marrow) at graft. The small numbers in the two groups and the very poor outcome make it difficult to conclude on the efficacy of purging.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1993

Indication and limits of megatherapy and bone marrow transplantation in high-risk neuroblastoma: a single centre analysis of prognostic factors.

76 patients with high risk neuroblastoma were treated with one (41 patients) or two consecutive courses (35 patients) of megatherapy. Autologous bone marrow transplantation was scheduled after each megatherapy. Univariate analysis confirmed two prognostic factors in this heterogeneous study population: no bone lesions before megatherapy and age at diagnosis of less than 2 years with 5-year progression-free survival rates of 51% (P < 0.0007) and 53% (P < 0.025), respectively. Both factors were shown to be of independent prognostic significance using the Cox proportional hazard model. Identification of prognostic factors should help to define the interest and limits of megatherapy. We consider that elective megatherapy followed by innovative treatments appears justified in patients with persisting bone disease. In contrast, megatherapy has to be re-evaluated for patients showing a more favourable response pattern and/or young age, ideally in a randomised, prospective trial.

Adolescent↗
PubMed1993

Multivariate analysis of prognostic factors in patients with non HIV-related primary cerebral lymphoma. A proposal for a prognostic scoring.

Between 1982 and 1991, 41 patients were treated for non HIV related primary cerebral lymphoma (PCL) in our institute. The purpose of this study was to perform a multivariate analysis of prognostic factors for survival in these patients. The presence of a CSF protein level over 0.6 g l-1 at diagnosis was found to be the most significant unfavourable prognostic factor in univariate analysis and had not previously been reported. Among the five significant prognostic factors at diagnosis, (age over 60 years, performance status--ECOG scale--over 2, memory dysfunction, non hemispheric tumour site, CSF protein level over 0.6 g l-1 at the diagnosis), three independent factors were identified in multivariate analysis: (1) CSF protein level (P = 0.007; RR = 4.7); (2) PS > 2 (P = 0.04, RR = 2.65); (3) age over 60 (P = 0.08; RR = 2.43). Using the regression coefficient of these three parameters, we determined a prognostic index which allowed us to distinguish three risk groups whose theoretical median survival is 4, 20 and 54, months respectively in patients with non HIV related PCL. These results indicate that PCL is an heterogeneous disease in terms of the prognostic in which three subgroups with discriminant survival can be identified.

Adolescent↗
PubMed1993

Patients with metastatic renal carcinoma candidate for immunotherapy with cytokines. Analysis of a single institution study on 181 patients.

This study was performed with the aim of discovering the characteristics and survival of patients with metastatic renal carcinoma who undergo immunotherapy with an Interleukin 2 based regimen. One hundred and eighty-one patients with metastatic renal carcinoma were referred to our institute from October 1987 until August 1991; 129 were treated with Interleukin 2 with or without Interferon alpha in three successive protocols. Fifty-two patients were not treated with immunotherapy due to the exclusion criteria of the protocols. Sixty-four patients with the same disease who had been referred to our institute before the initiation of this programme (1982, 1987) were also analysed as a control group. The main characteristics of the three different cohorts of patients were analysed and compared with univariate statistical tests; the median survival of the patients was calculated and compared. The referral rate increased from 13 a year to 45 a year while the IL2 trials were being conducted. Patients treated with cytokines have a median survival of 18 months after occurrence of metastases, compared to 6 and 8 months, respectively, in excluded patients and the control group. This parameter is of 15 months when the 181 patients, treated with cytokines or not, are considered. The survival of treated vs excluded patients is significantly different (P < 10(-6); so is the survival of the 181 patients recently included when compared to the historical group (P:10(-5). When the 181 recent patients are compared to the historical control group, a number of differences appear in their characteristics, which prevent us from drawing any conclusion about the role of immunotherapy in the improvement of survival observed. This study clearly evidences the selection of the patients receiving immunotherapy and the modification in referrals of a disease induced by a new available therapy. This emphasises the need for prospective studies in this setting.

Adult↗
PubMed1993

[Neuroblastoma in the Auvergne region from 1986 to 1991: epidemiological data].

An epidemiological study of neuroblastoma in the Auvergne area of France (departments: Puy-de-Dôme, Allier, Cantal, Haute-Loire) was carried out over a 6 years period (1986-1991). Nineteen cases of neuroblastoma were registered during this period. The annual incidence rate is 1.2 among 100,000 children under the age of 15 years. Similar incidence rates from other studies have been reported in the literature. In the department of Rhône, France, a screening program for neuroblastoma was initiated in 1990. The Auvergne area may constitute a population-based control group.

Child↗