Biomedical subjects

P Bret

Publications and source records attributed to P Bret.

At least 19 recordsLinked to original sources

PubMed2005

[Results of the Sainte-Anne - Lyons series of 318 oligodendroglioma in adults].

INTRODUCTION: Incidence of cerebral oligodendrogliomas is increasing because of better recognition made possible by improved classifications. We studied a homogeneous series using the Sainte-Anne grading scale in order to better understanding the history of these tumors with or without treatment and to assess prognosis and associated factors. PATIENTS AND METHODS: A retrospective series of 318 adult patients with oligodendroglioma (OLG) treated at Hôpital Sainte-Anne, Paris (SA) and Hôpital Neurologique, Lyons (L) between 1984 and 2003 was analyzed: 182 grade A OLG (SA + L), 136 grade B among which a homogenous series of 98 (SA) were included. For grade A: age at diagnosis ranged from 21 to 70 (mean: 41), sex ratio was 1.28. For grade B: age at diagnosis ranged from 12 to 75 (mean: 45.5), sex-ratio was 1.58. The main first symptoms were: epilepsy (A: 91.5%; B: 76%), intracranial hypertension (A: 7.9%; B: 14.6%), neurological deficit (A: 5.1%; B: 17.7%). The most frequent locations were: frontal, insular and central for both A and B. Mean size was 55 mm for grade A, 62 mm for B. Calcifications were found in 20% of A, 48.5% of B. No tumor was enhanced on imaging (CT/MRI) in grade A, all but 7 in grade B. All patients underwent surgery either for biopsy (A: 47.2%; B: 53%), or removal which was partial (A: 26.4% vs B: 19.4%) or extended (A: 36.3% vs B: 37.8%). Fifty-six patients underwent 2 procedures and 12 three procedures. Radiotherapy was performed in 76.9% of grade A, and 91% of B patients, in the immediate postoperative period for 71% A and 82.7% B. Chemotherapy was delivered for 36% of grade A (in the event of transformation to grade B or failure of radiotherapy) and 67.5% of B patients. Among grade A tumors, 38% transformed into grade B within a mean delay of 51 months with a mean follow-up of 78 months. RESULTS: Median survival was 136 months for grade A and 52 for grade B. Survival at 5, 10 and 15 was 75.5%, 51% and 22.4% for grade A vs 45.2%, 31.3% and 0% for grade B respectively. In univariate and multivariate analysis, grade A survival was associated with age at diagnosis, tumor size, large removal and response to radiotherapy. Grade B survival was associated with age at diagnosis, wide removal and sharply defined limits of the tumor on imaging. CONCLUSIONS: Analysis of both published data and this series underlines many prognostic parameters. It shows that OLG are heterogeneous tumors even in each grade (A and B). Treatment should consequently progress towards more targeted procedures for patients mainly with postoperative radiotherapy and chemotherapy.

Adolescent↗

PubMed2005

[Adult supratentorial oligodendrogliomas. Surgical treatment: indications and techniques].

Surgical resection is the first step in the treatment of adult supratentorial oligodendrogliomas (OLG). However, the role of resection on prognosis, the most appropriate time for surgery along the natural history of those tumors, and the best operative strategy remain debated. Survival curves after resection vary greatly among reported series, in particular as a result of a persisting confusion in identification and classification of cerebral OLG. Surgical or stereotactic biopsy is the first surgical procedure which enables confirmation of the diagnosis suggested on imaging, assessment of extension of tumor cell infiltration beyond abnormalities limit described an imaging, and currently available molecular biology studies. Biopsies may be the only surgical procedure in patients having a deep-seated tumor with minimal mass effect, or prior to a surgical resection or a "wait and watch" strategy. Surgical resection is indicated for the other patients. However, it has not been demonstrated that time for resection has an influence on survival, excepted in patients with rapidly growing tumors, with mass effect causing increased intracranial pressure. A wait and watch strategy is therefore warranted in patients with a tumor aspect suggestive of a grade A OLG; surgical resection may be indicated later. There is a current trend for maximal safe resection, preserving functional cerebral areas, since truly complete resection of the tumor including infiltration is exceptional. However, from the contradictory results reported to date, one cannot ascertain whether large or complete resection based on imaging is associated with significantly longer survival. Neuronavigation guidance, intraoperative imaging, and cortical stimulation techniques are helpful neurosurgical techniques enabling maximal safe resection with preservation of functional areas.

Adult↗

PubMed2004

[Intra-cavernous aneurysm of the internal carotid artery complicating sphenoid sinusitis].

INTRODUCTION: Mycotic or post-infectious aneurysm of the intra-cavernous portion of the internal carotid artery is uncommon. CASE REPORT: We report here the case of a patient who developed progressive left ophthalmoplegia, with left hemi-crania three weeks after a tooth extraction. The patient was febrile. Neuroradiological and microbiological analysis led to the diagnosis of sphenoidal and ethmoidal sinus infection with extension to the left cavernous sinus. An aneurysm of the intra-cavernous portion of the left internal carotid artery was also found. CONCLUSIONS: The risk of rupture for this kind of aneurysm is difficult to assess. Treatment always consists in prolonged and adapted antibiotic therapy. For certain patients neurosurgical or endovascular repair is necessary. We followed our patient for four Years without surgical intervention. The diameter of the aneurysm has remained stable.

Anti-Bacterial Agents↗

PubMed2004

'Parcours de Femme 2001': a French opinion survey on overall disease and everyday life management in 1870 women presenting with gynecological or breast cancer and their caregivers.

PURPOSE: The aim of the survey 'Parcours de Femmes 2001' was to evaluate the overall management and care of women with female cancers and to determine their needs. METHODS: Women with breast or gynecological cancer who had either received at least 3 months of treatment or had completed treatment <1 year before the study were enrolled in this cross-sectional, observational study. RESULTS: From February to November 2001, 2839 questionnaires were distributed; 1870 were returned (66% response rate), mainly by breast cancer patients (87%). While 92% of women reported having received information at diagnosis, 34% of relapsed patients complained of lack of information concerning their disease and treatment. Only 18% of patients were included in the treatment decision process and 66% of women obtained complementary information from the media, patients and care professionals. Fatigue was the most severe problem quoted (78% of cases) and was poorly managed by caregivers due to diagnostic and treatment difficulties. Problems relating to family and to affective and socio-professional life were poorly identified and remained largely unmanaged. CONCLUSIONS: Information given to female cancer patients must be improved in relapsed patients, particularly regarding the adverse effects of treatment. Psychosocial management requires a more holistic approach through new channels, together with the coordination of existing structures.

Activities of Daily Living↗

PubMed2003

Conformal irradiation for pure and mixed oligodendroglioma: the experience of Centre Leon Berard Lyon.

PURPOSE: To assess whether conformal radiotherapy (CRT) after incomplete surgery or biopsy for pure oligodendrogliomas and mixed gliomas results in decreased long-term sequelae without impairing local control and while reducing irradiated volume. MATERIALS AND METHODS: Twenty-six consecutive patients who presented with pure (21) or mixed (5) oligodendrogliomas and who were given incomplete resections were treated according 3 different strategies: CRT alone (12), chemotherapy followed by CRT (4), and chemotherapy and delayed CRT at the time of tumor progression (10). CRT consisted of multiple noncoplanar fields. Median dose was 60 Gy. Quality of CRT was assessed using tumor and normal tissue conformal indexes. The location of recurrences was assessed with MRI and dosimetric data. Late sequelae were assessed by a questionnaire exploring professional outcome, and also by a Mini Mental State Examination test. RESULTS: The mean overall survival was 5.2 years. Fifteen patients experienced a local relapse. All but 1 occurred in the 95% isodose. Among 11 nonevolutive patients, 6 have a full-time or part-time job. CONCLUSIONS: Despite CRT, infield recurrence was a common feature in patients with oligodendrogliomas and mixed tumors. Further research, including molecular biology typing of tumors and type of treatment, is warranted to improve survival and quality of life.

Adult↗

PubMed2003

Technical refinements for validating functional MRI-based neuronavigation data by electrical stimulation during cortical language mapping.

Preoperative functional neuroimaging techniques represent an appealing method to localize language areas in tumor surgery, but their reliability still needs to be confirmed by accurate comparison with more invasive but validated mapping techniques like intraoperative electrical cortical stimulation. Two patients harboring a glioma involving speech areas underwent mapping of language function by preoperative functional magnetic resonance imaging (fMRI), whose results were integrated into the neuronavigation device, and by intraoperative electrical stimulation mapping (ESM). The utilization of neuronavigation allowed us to estimate the degree of spatial correspondence between language areas detected by the two techniques. Language areas identified by functional magnetic resonance imaging on the cerebral cortex exposed during surgery corresponded to those identified by invasive mapping in both patients. It was possible to achieve a gross total tumor removal while respecting language areas in both cases, with no permanent postoperative phasic aggravation. The concordance of results between pre- and intraoperative mapping techniques in our patients indicates that preoperative fMRI language mapping may prove useful when planning the resection of intracerebral lesions in language areas. However, accurate neurofunctional imaging protocols and image analysis are crucial to obtain a preoperative language mapping that is in agreement with ESM findings.

Brain Mapping↗

PubMed2002

Is normal pressure hydrocephalus a valid concept in 2002? A reappraisal in five questions and proposal for a new designation of the syndrome as "chronic hydrocephalus".

The authors question the current validity of the traditional concept of normal pressure hydrocephalus (NPH) as it was described by Adams and Hakim in 1965. The classic features of the disease are addressed. It is concluded that most of the historical statements made three decades ago need to be revised. Especially, the term "normal pressure" hydrocephalus probably does not match the actual manometric profile of patients with NPH. Similarly, the terms"curable"and "reversible" dementia are inadequate to designate the mental alterations of NPH. That NPH is non-specific to the adult population is also stressed, since it may be not uncommonly encountered in paediatrics, especially in an implanted shunt malfunction. The term "chronic hydrocephalus" without reference to cerebrospinal fluid pressure and to the age of the patient is proposed instead of NPH, which seems out of step with current knowledge of the pressure profile and with the diagnosis and decision making context in patients with so called NPH.

Age Factors↗

PubMed2001

Differential expression of somatostatin receptors in ependymoma: implications for diagnosis.

Somatostatin receptors (SSts) have been found in a variety of brain tumors, e.g., meningiomas, medulloblastomas and astrocytomas. Our aim was to investigate their expression in ependymomas. Using RT-PCR, expression of mRNA for the different SSt subtypes was analyzed and quantified in 28 ependymomas and correlated with different variables (age, tumor location, histological grade, recurrence and survival). In addition, in 8 cases, protein expression was studied in vitro, using immunohistochemistry, and in vivo, by somatostatin scintigraphy. mRNAs for all 5 subtypes were variably expressed in each ependymoma. The Southern blotting signal obtained after SSt(1) and SSt(2) amplification was higher than that for the other receptor subtypes. No significant correlation was seen between the level of SSt(1) and SSt(2) mRNA expression and age, location, histological grading, recurrence or survival. In the 8 cases, SSt(1) staining was negative in 3 and low in 5. Staining for SSt(2A) was positive but low in every specimen analyzed. SSt(1) and SSt(2) immunoreactivity was seen only in the cytoplasm of tumoral cells. Somatostatin scintigraphy showed clear uptake, which agreed with MRI data in the majority of cases. However, no correlation was seen between tracer uptake intensity and histological grade, SSt(1) and SSt(2) mRNA expression or immunostaining intensity. This evidence for the expression of SSt(2) receptors in ependymomas opens interesting prospects for their follow-up.

Adolescent↗

PubMed2001

Central nervous system cavernomas in the pediatric age group.

Pediatric CNS cavernomas still are diagnostically and therapeutically challenging lesions. With the help of magnetic resonance imaging, the natural history of cavernomas now guiding therapeutic strategies is well documented in adults but remains poorly known in the pediatric age group, since most previous studies dealt with adult and pediatric patients together. This paper focuses on clinical, imaging, and therapeutic features and differential diagnosis of CNS cavernomas with an emphasis on their specificities in the pediatric age group. It is based upon a critical review of the literature and our single-center experience with 36 children (35 with cerebral cavernomas and one with spinal cord cavernoma) operated on during the period of 1985-1999 as well as with seven additional unoperated pediatric cases. Our experience resembles that of other authors regarding the high hemorrhagic risk in children compared to adults. These angiographically occult vascular malformations are often revealed by the sudden onset of intracerebral hematoma with acute focal neurologic deficits, concomitant manifestations, and/or signs of raised intracranial pressure. True epilepsy is less common and may be related to chronic or recurrent microbleeding. Evocative imaging findings are also somewhat different in the two age groups, and we propose here an imaging classification of cerebral cavernomas based on both morphological and signal characteristics that is applicable to the pediatric age group. A sharply demarcated spherical intracerebral hematoma or heterogeneous lesion should always make one consider the hypothesis of a cavernoma. For symptomatic lesions and most rapidly growing asymptomatic lesions, the treatment of choice is complete microsurgical excision preceded by careful anatomical and functional evaluation. Improvements in surgical techniques and anesthesiology over recent years have brought good results in most operated children. The limited role of radiosurgery in the management of pediatric cerebral cavernomas is discussed. There is still a need for well-conducted specific evaluation of the natural history of these lesions in the pediatric age group to aid in systematic research, follow-up, and therapeutic strategies for asymptomatic cavernomas.

Central Nervous System Neoplasms↗

PubMed2001

Hypothalamic hamartoma: the role of surgery in a series of eight patients.

Hypothalamic hamartoma are rare lesions. We report a new series of eight patients treated for precocious puberty (six cases) or gelastic seizures (two cases). Surgical resection was total in four cases (three pediculated and one sessile). Precocious puberty was controlled by surgical treatment in all cases. Gelastic seizures were controlled by medical treatment, but the patients did not become seizure free. We observed no mortality and no endocrinological or visual morbidity. The fact that a vascular "rete mirabilis" was observed on the surface of the lesion in our surgical material is an argument favoring a vascular mechanism in precocious puberty. Coagulation of this vascular structure can help control precocious puberty. Our series confirms that the hypothalamic hamartoma can be surgically treated when patients fail to respond to medical treatment, when the length of the treatment cannot be tolerated by the chidren and their families, and when there are uncontrolled gelastic seizures

Adolescent↗

PubMed2001

The value of cortical stimulation applied to the surgery of malignant gliomas in language areas.

This study analyzes the utility of peroperative cortical language mapping applied to the surgery of high-grade gliomas situated within or in close vicinity to speech areas. Fifteen consecutive patients harboring high-grade gliomas located in the dominant hemisphere, causing regressive or minor language troubles, underwent awake craniotomy in our institution between June 1998 and April 2000. The technique of cortical stimulation under local anesthesia for language mapping, initially described by Ojemann and colleagues, was applied with some modifications. All patients tolerated awake craniotomy except one, who was intubated after the mapping procedure. Mapping results confirmed a high variability in location of language sites. It was possible to achieve a gross total tumor removal in all cases. Nine patients (60%) exhibited a transient postoperative aggravation. Two patients (13%) presented permanent phasic aggravation. One patient died 16 days after surgery from pulmonary embolism. Five patients died for tumor progression, with a mean survival time of 16.4 months and a median high-quality survival period of 14.2 months. With a mean follow-up of 9.9 months (range, 18-6 months), the 9 survivors are recurrence-free and reveal no significant change in linguistic abilities. This technique is well tolerated and consents to maximize the extent of surgical removal while minimizing the risks of permanent postoperative deficits. This results in an improvement of survival and quality of life.

Adult↗

PubMed2001

Visceral cancer metastasis to pituitary adenoma: report of two cases.

BACKGROUND: We report two cases of metastases from visceral cancers to pituitary adenomas, and review the literature. CASE DESCRIPTION: Two female patients, aged 75 and 87 years, underwent transesophageal surgery for presumably benign pituitary adenomas. Using extensive immunostaining studies, histopathological examination showed that the surgical specimens from both patients were composed of metastatic deposits within gonadotropin adenomas. Fourteen cases of metastases to pituitary adenomas have been mentioned in 11 reports in the literature. In all cases, the correct diagnosis was made after autopsy or histopathological studies, even in patients known to suffer from visceral malignancies. In our cases, immunohistochemical studies were conclusive in characterizing the two distinct tumor components. The pathogenetic mechanisms favoring the development of metastases in pituitary adenomas are discussed, especially those altering the normal hypophyseal circulation. CONCLUSION: Neurosurgeons performing pituitary surgery should be aware of the possibility of metastases in pituitary adenomas.

Adenoma↗

PubMed2001

Redifferentiation therapy in brain tumors: long-lasting complete regression of glioblastomas and an anaplastic astrocytoma under long term 1-alpha-hydroxycholecalciferol.

PURPOSE: Classical and new therapies in anaplastic astrocytomas and glioblastomas do not yield sufficient results. Agents able to redifferentiate neoplastic cells in vitro are known. We proposed alfacalcidol, a vitamin D analog able to bind to nuclear receptors regulating mitotic activity, in the treatment of malignant gliomas. PATIENTS AND METHODS: Patients with glioblastomas and anaplastic astrocytomas were enrolled in a phase II trial involving surgery or biopsy, radiotherapy (64 Gy), chemotherapy with VM26-CCNU or fotemustine, and alfacalcidol at the daily dose of 0.04 microg/kg. MRI took place every 6 months. RESULTS: Eleven patients were included and completed the study. The series involved 10 glioblastomas and 1 anaplastic astrocytoma. Three patients out of 11 patients (27%), 2 glioblastomas and 1 astrocytoma grade III, exhibited a particular response, consisting in the progressive regression of the radiological lesion, with a decrease of the gadolinium-enhanced area. Simultaneously, the patients showed a complete clinical remission, observed respectively for 7, 5 and 4 years. In the series of 10 patients with glioblastomas, 2 cases showed this response; after 4 years, 2 of 10 patients with glioblastomas (20%) were alive; the median survival time is 21 months. Normal or subnormal calcemia was observed, at the dose proposed, so that no interruption of the drug was necessary. CONCLUSIONS: Alfacalcidol, an in vitro agent of redifferentiation, is safe and seems able to induce in some patients, in synergy with classical surgery-radiotherapy-chemotherapy treatments, a particular progressive and durable regression of the tumor. The responders might represent about 20% of malignant gliomas.

Adjuvants, Immunologic↗

PubMed2001

Differential expression of somatostatin receptors in medulloblastoma.

OBJECT: Somatostatin receptors have been found on a variety of tumours like neuroendocrine breast or brain tumours. Their detection opens new diagnostic and therapeutic paths. The aim of this work was to investigate their expression in medulloblastomas. METHODS: Using both techniques, reverse transcriptase-polymerase chain reaction and immunohistochemistry, we analysed mRNA of different subtypes of somatostatin receptors in 15 medulloblastomas and the localisation of the subtype SSTR2 receptor at the cellular level in 13 medulloblastomas. All five subtypes mRNA were variably expressed in each medulloblastoma. The signal obtained after Southern blotting for SSTR2 receptor amplification was the highest as compared to the signal obtained for the other receptor subtypes. Immunostaining for SSTR2A receptor was present in every tumour specimen and was specifically located to the cellular membrane of neoplastic cells. No staining was identified at the level of peritumoral veins. CONCLUSION: The evidence of predominant expression of SSTR2 receptors in medulloblastomas opens interesting prospects for their diagnosis and therapy.

Cerebellar Neoplasms↗

PubMed2001

[Perioperative cortical stimulation of language fields under local anesthesia in preparation to excision of tumors of the dominant hemisphere].

OBJECTIVES: The aim of this study is to demonstrate the accuracy of direct cortical stimulation of language areas preparatory to the removal of infiltrating tumors of dominant hemisphere. MATERIAL AND METHODS: From June 1998 to March 2000 we included in our study 15 patients, aged from 30 to 75 years, harboring gliomas (14 high grades and 1 low grade) close to language-specific cortex. All patients had slight inaugural phasic troubles. They underwent craniotomy under local anesthesia for cortical stimulation language mapping, in conjunction with electrocorticography to identify the after-discharge threshold. Stimulation mapping covered the entire macroscopically tumor involved area, extending up to 3 cm away from the margins of the lesion, without searching to identify systematically the language areas. Therefore, the lesion was removed as completely as possible, respecting a security margin of at least 1 cm from the recognized language sites. RESULTS: We identified from 1 to 6 language sites for 14 of our patients, in different locations. A radical removal was achieved for all high grade gliomas, while the low grade was only partially removed. A patient died on the 16th postoperative day from pulmonary embolism; 2 patients deteriorated from peri- or immediate postoperative complications; 9 showed a transient neurological worsening that receded by the 2nd postoperative month, while 3 did not present any postoperative aggravation. At a follow-up of 1 month to 2 years (mean 8 months), 6 patients died and the 9 survivors maintain a good life quality. CONCLUSIONS: Cortical stimulation for language mapping is an accurate technique that allows the surgical morbidity of lesions in proximity to language areas to decrease and become comparable to the surgical morbidity for lesions in non eloquent areas.

Adult↗

PubMed2000

Zero rate of shunt infection in the first postoperative year in children--dream or reality?

The rate of infectious complications following shunt implantations at the Pierre Wertheimer Hospital was 6.4% in 1992-1994. In order to improve this infection rate, new recommendations for surgery were applied and a new type of valve was used. The effects of these measures after a 1-year follow-up were analyzed in 70 patients. The rate of infection was zero, 2.8, and 4.3% at 2, 6, and 12 months, respectively. A case-control study did not reveal any significant risk factor among the patient and surgical factors analyzed.

Adolescent↗

PubMed2000

Tentorial meningiomas. Report on twenty-seven cases.

OBJECTIVE: Report our experience with 27 tentorial meningiomas (TM) surgically treated between 1985 and 1998. METHODS: The records of 27 patients with TMs were retrospectively reviewed for clinical presentation, neuroradiological evaluation, surgical treatment and long-term outcome. The extent of tumor resection was scored according to the Simpson's grading for tumor removal. Long-term results were evaluated according to the Glasgow Outcome Score (GOS). RESULTS: The average age was 53 years. Female predominance was 74%. The most common complaints at presentation were headaches (51%), gait ataxia (33%), memory disturbances (30%) and hypoacousia (30%). A classification of TMs into 5 subgroups according to tumor site is proposed on the basis of imaging studies. A cerebrospinal fluid shunt was established prior to direct approach in 7 patients and as the sole procedure in one inoperable patient. Twenty-seven direct approaches were undertaken in 26 patients, including 17 infratentorial and 10 supratentorial approaches. Total tumor removal was achieved in 20 patients (77%) and subtotal removal in 6 (23%). Fifteen patients (55%) experienced 22 postoperative complications. One patient died three months after a subtotal resection (mortality = 3.7%). With a mean follow-up of 54 months, all 26 survivors are currently alive with 23 having resumed their normal activities and 3 needing assistance. Five of 6 patients with subtotal resection survived and were followed for a period ranging from 72 to 132 months: none showed residual tumor progression and no re-operation was considered. An additional patient experienced a ( ) recurrence 6 years after total removal, with no tumor progression 2 years after his recurrence was recognized. DISCUSSION: The best surgical approach to TMs is still a controversial matter. The advantages and drawbacks of conventional versus transbasal approaches are reviewed. Our experience suggests that subtotal removal can be associated with long recurrence-free intervals and preserved quality of life. TMs located at the tentorial edge carried a definitely worse prognosis than peripheral forms.

Adult↗

PubMed1999

Diffuse brain stem tumor in an adolescent with multiple enchondromatosis (Ollier's disease).

Among patients with enchondromatosis, those with Ollier's disease are usually considered to be at a lower risk for extra-osseous malignancy than those with Maffucci's disease. However, several reports suggest that Ollier's disease may also be associated with gliomas. We report here the youngest patient in the literature (16 years) to be detected with a brain tumor and Ollier's disease. This is also the first case with diffuse brain stem involvement. Thus, counselling of patients with Ollier's disease may become more difficult than initially thought.

Adolescent↗