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P Paquis

Publications and source records attributed to P Paquis.

At least 19 recordsLinked to original sources
PubMed2005

[Stabwound of the cervical spinal cord. Two case reports].

Two cases of Brown-Sequard syndrome following a stab wound of the cervical spinal cord are reported. Spinal cord hemisection was confirmed by magnetic resonance imaging and surgical exploration. Both patients presented leakage of the cerebrospinal fluid and underwent surgical repair. In the first case, the pia-mater was sutured to close the wound and decrease the risk of post-traumatic syringomyelia. Outcome at ten and two years follow up was good in both patients who were able to walk. One of them returned to work. The contribution of surgical repair of spinal cord stab wounds and mechanisms of recovery are discussed.

Adult↗
PubMed2004

Long-term outcome of oligodendrogliomas.

BACKGROUND: Favorable prognostic factors for oligodendroglial tumors include age younger than 40 years, low tumor grade, and extent of resection. OBJECTIVE: To assess survival time and prognostic factors of 100 patients with oligodendrogliomas diagnosed between 1995 and 2002. METHODS: The tumors were rated histologically by the WHO classification as low grade (grade II) or anaplastic (grade III). One hundred patients were categorized into three groups: group A: grade II, group B: secondary grade III (low grade with anaplastic transformation during the follow-up), group C: de novo grade III. All patients were symptomatic at presentation and underwent neurosurgical procedure for histologic diagnosis. Follow-up was performed with clinical assessment, brain MRI, and MIBI scintigraphy. RESULTS: There were 66 men and 34 women (mean age at diagnosis 46.7 years). The most common first symptom was partial epileptic seizure (75%). Fifty-six patients had initial gadolinium enhancement (A: 15.6%; B: 36.8% as grade II, 95% as grade III; C: 90%), generally associated with MIBI hypermetabolism (p < 0.0001). Survival rates at 2, 5, and 10 years were A: 88%, 88%, 85%; B: 79%, 64%, 42%; C: 43%, 16%, 15%. CONCLUSIONS: Secondary anaplastic oligodendroglioma patients were younger than patients with de novo anaplastic oligodendrogliomas. Histologic confirmation is mandatory because some low grade oligodendrogliomas had gadolinium enhancement on MRI and some anaplastic did not. Survival time was longer for secondary than for de novo anaplastic oligodendrogliomas without difference in the duration of the malignant phase of the disease.

Adolescent↗
PubMed2004

[Infratentorial localisation of a dysembryoplastic neuroepithelial tumor. A case report].

Neuroepithelial dysembryoplastic tumor (DNT) is usually considered as a supratentorial benign neoplasm. DNT of the posterior fossa is a very rare entity and only four previous cases were reported in the literature. We describe a case of a 26-Year-old woman presenting recurrent episodes of vertigo. Magnetic resonance imaging revealed four cystic lesions located in the cerebellum, hypointense on T1-weighted images and hyperintense on T2-weighted images, without gadolinium enhancement. After partial resection, histological examination showed small glial cells, oligodendrocytes-like, lying in an eosinophilic alveolar matrix with some floating neurons. Due to this specific glioneuronal element, the diagnosis of DNT was retained. We discuss the clinical and radiological particularities of this infratentorial location and compare our case with those previously described in the literature.

Adult↗
PubMed2004

[Neoadjuvant chemotherapy for symptomatic non operable grade II fibrillary astrocytoma in adults].

We collected 6 case-reports of symptomatric non removable low grade fibrillary astrocytoma of adults treated with a procarbazine-CCNU-vincristine chemotherapy regimen. All patients had drug-resistant epilepsy but brain imaging was stable. Total gross resection was rejected because of Volume or tumor location. After 4 to 7 cycles of chemotherapy, 2 patients had partial response and one minor response on brain MRI. All of them were seizure-free. Progression free survival was not reached at 5 Years. Up-front chemotherapy for low-grade astrocytomas may be useful and has to be prospectively evaluated.

Adult↗
PubMed2002

[Delayed diagnosis of neurocysticercosis: two case reports].

INTRODUCTION: Neurocysticercosis is the most frequently encountered cerebral parasitic infection worldwide. It is due to infection of the central nervous system by Taenia solium larval form. According to the location of the cysts, parenchymal and extra-parenchymal forms may be identified, with different clinical expressions. EXEGESIS: We report two cases of neurocysticercosis, one with typical parenchymal involvement and the second with extra-parenchymal involvement revealed by increased intra-cranial pressure. In both cases, the diagnosis was established over 10 years after the onset of symptoms. CONCLUSION: Neurocysticercosis is very frequent in non-Islamic developing countries, and its incidence is increasing in industrialized nations in relation to tourism and immigration from highly endemic areas. Symptoms usually appear several years after infection and this accounts for the frequent delays before the diagnosis is established.

Adult↗
PubMed2002

Endovascular treatment of ruptured intracranial aneurysms in patients aged 65 years and older: follow-up of 52 patients after 1 year.

BACKGROUND AND PURPOSE: We sought to describe the clinical outcome and results obtained in the endovascular therapy of ruptured cerebral aneurysms in the elderly over an 8-year period. We compared endovascular therapy results in patients aged > or =65 and <65 years. METHODS: During 1993-1999, 52 patients aged 65 to 85 years (mean age, 71.5+/-4.7 years) were embolized with the use of Guglielmi detachable coils (group I). During the same period, 143 patients aged <65 years (mean age, 47+/-11 years) with ruptured cerebral aneurysm were treated with the same technique (group II). A clinical assessment was made on admission with the Hunt and Hess (HH) classification and again in the 12th month with the Glasgow Outcome Scale (GOS), with arteriographic control in months 3 and 12. RESULTS: In group I, clinical grades on admission were as follows: HH 1, 9.5%; HH 2, 33%; HH 3, 21%; HH 4, 34.5%; HH 5, 2%. Outcome was favorable in 48% of patients (GOS 1 or 2); the mortality rate was 23%. No rebleeding was observed. Patients presenting lesions > or =10 mm had an unfavorable outcome in >77% of cases. Thromboembolic complications were present in 13% of cases. In group II, clinical grades on admission were as follows: HH 1, 14.5%; HH 2, 47%; HH 3, 11%; HH 4, 24%; HH 5, 3.5%. Favorable outcome (GOS 1 or 2) was observed in 77% of cases, with 14% mortality. Complications due to the endovascular procedure were present in 4.2% of cases. Patients with HH grades 1 or 2 on admission showed a positive outcome (GOS 1 or 2) in 77% of cases in group I and in 88.5% of cases in group II. Mortality was 9% in the first subgroup compared with 2.8% in the second. Patients who had a high clinical grade on admission (HH 4 or 5) showed a favorable outcome (GOS 1 or 2) in 16% of cases in group I compared with 41% in group II. CONCLUSIONS: Endovascular treatment of ruptured intracranial aneurysms in patients aged > or =65 years appears to be effective against rebleeding and represents an alternative to surgery. However, perioperative thromboembolic complications are more frequent in the elderly population.

Adolescent↗
PubMed2001

Vertebral metastases from pineoblastoma.

Two male patients aged 26 and 18 years presented with vertebral metastases originating from pineoblastomas on which surgery had been performed 8 years and 5 months earlier, respectively. In the first case in which the metastasis developed in the T8 corpus, the disease is presently under control after high-dose chemotherapy and autologous blood stem cell transplantation. The second patient (sacral metastasis), despite aggressive adjuvant therapy, died 2 years after the last operation because of spinal seeding. These uncommon cases are discussed with reference to the literature on extraneural metastases that originate from neuroepithelial tumors of the central nervous system.

Adolescent↗
PubMed2001

[Factors influencing recurrence and role of radiotherapy in filum terminale ependymomas. 14 cases and review of the literature].

PURPOSE: We reviewed a series of 14 cases of filum terminale ependymoma and 264 cases in the literature, to study the characteristics of these tumors and specifically to determine factors influencing recurrence. MATERIAL AND METHODS: This series analyzed data between 1984 and 1998. The mean follow-up period was 5.5 years and the median age 40 years. Pain was the first symptom, except in one case, with progressive sensitive-motor deficit. Four patients had a myelography and a CT scan, and ten a MRI. All patients were operated with a total resection in 12 cases. All tumors, except one, were a myxopapillary ependymoma. RESULTS: Clinical results were excellent in 2 cases, good in 8, stable in 2 and worse in 2. Two patients had a recurrence after an initial sub-total resection, both were operated on again, followed by post-operative radiotherapy. Among the 278 filum terminale ependymoma, removal was total in 200 (72%). A recurrence occurred in 15% of them after total removal, and in 43% after partial removal (p<0.001). Among patients with partial removal, recurrence was observed in 33% of them if they had post-operative radiotherapy, and in 55% of them if they did not have post-operative radiotherapy (p<0.05). CONCLUSION: The extent of tumor removal has a statistically significant effect upon recurrence. This review is in favor of post-operative radiotherapy in case of partial removal, but this systematic attitude can be discussed after a critical analysis of this study. Long term follow-up is mandatory due to the possibility of late recurrence.

Adult↗
PubMed2001

[Value of endonasal endoscopic surgery in the treatment of sphenoid cerebrospinal rhinorrheas. 15 cases].

UNLABELLED: Surgical management of cerebrospinal fluid leaks (CSFL) has improved these few past years with the development of paranasal sinus surgery under optical guidance. CSFL localized in the sphenoid sinus represent only 5 to 15% of all CSFL. The authors have analyzed a serie of 15 patients having undergone surgery from 1992 to 1999 for CSFL: 10 cases followed pituitary gland surgery realized through sublabial-transsphenoidal approach, 2 cases followed head trauma, 1 case followed a secondary neurosurgical procedure following recurrence of a rathke's cleft cyst, 1 case followed medical treatment of a bulky pituitary gland adenoma and 1 case was associated to an empty sella syndrome. The surgical procedure has relied on sphenoid sinus approach through the sphenoethmoidal recess (SER) (n = 8), transethmoidal approach (TE) (n = 2) or transseptal approach (TS) (n = 7) followed by a filling of the defect by a graft of fat with biological glue (n = 17). Sometimes it was associated to a cartilagenous graft (n = 7) when there was a bone defect. The average period of hospitalisation was 5.2 days (4-21), mean follow-up was 2.9 years (6 months-7 years). RESULTS: The success rate was 80% (3 failures were observed), 2 patients underwent secondary procedures by TS approach with success. Our results combined with the literature data led us to propose an alternative surgical strategy adapted to each case. Endonasal surgery under optic guidance compared to the transrhinoseptal approach represents an attractive alternative with less undesirable iatrogenic consequences.

Adipose Tissue↗
PubMed2000

Parenchymal pineal tumors: a clinicopathological study of 76 cases.

PURPOSE: The aim of this study was to identify factors that could lead to optimization of the management of pineal parenchymal tumors (PPT) which remains equivocal and controversial. METHODS AND MATERIALS: In order to determine factors that influence PPT prognosis, a series of 76 consecutive patients from 12 European centers with histologically proven tumors was retrospectively reviewed. The clinical records and material for histologic review were available in all cases. Follow-up was achieved in 90% of cases. RESULTS: According to WHO classification, there were 19 pineocytomas, 28 intermediate and mixed PPT, and 29 pineoblastomas. According to a four-grade institutional classification, there were 11 Grade 1, 27 Grade 2, 20 Grade 3, and 18 Grade 4. Surgical resection was attempted in 44 patients, whereas 30 had biopsy only. In one case, diagnosis was made at autopsy and in another on spinal deposits. Forty-four patients were irradiated following surgery, 15 patients received chemotherapy. Forty-one patients were alive (median follow-up: 85 months); 9 patients died perioperatively; 26 patients relapsed. Univariate analysis showed a good outcome correlated with age above 20 years, tumor diameter less than 25 mm, and low-grade histology. Multivariate analysis confirmed histology and tumor volume to be significant independent prognostic factors. The extent of surgery and radiotherapy had no clear influence on survival. CONCLUSIONS: This review highlights the prognostic features of PPT and may help to determine treatment strategies based on radiologic and pathologic characteristics.

Adolescent↗
PubMed2000

Fluorescence in situ hybridization study of aneuploidy of chromosomes 7, 10, X, and Y in primary and secondary glioblastomas.

The aneuploidy of autosomes 7, 10, and sex chromosomes (X and Y) was analyzed in a series of 44 primary (de novo) and 20 secondary glioblastomas using fluorescence in situ hybridization (FISH) on smear preparations of glioma tissue. The tumors were screened for trisomy 7, monosomy 10, as well as loss of the Y chromosome and disomy of the X chromosome in male subjects, and monosomy of the X chromosome in female subjects. We found that taken alone or in combination, these chromosomal abnormalities do not appear to be characteristic of a glioblastoma subtype; therefore, they do not allow the differentiation between primary and secondary glioblastomas. Also, the loss of a chromosome 10 appears to be an earlier event than a gain of a chromosome 7 for the genesis of a secondary glioblastoma.

Aneuploidy↗
PubMed2000

Expression of vascular endothelial growth factor-b in human astrocytoma.

Growth of human malignant gliomas is stringently dependent on an angiogenic process that probably involves vascular endothelial growth factor (VEGF). Expressions of mRNA coding for the different forms of VEGF were analyzed in surgical specimens from human astrocytomas. Low levels of placental growth factor (PGF) and VEGFC mRNA were observed in polymerase chain reaction, but not in Northern blot experiments. VEGF mRNA was found in some but not all grade and grade IV astrocytomas. VEGFB mRNA was observed in all tissue samples analyzed irrespective of the tumor grade. A new splice variant of VEGFB (VEGFB155) that lacks exons 5 and 6 is described. Expressions of VEGF mRNA in cultured glioblastomas cells were upregulated by hypoxia, but the sensitivity of the cells to hypoxia was reduced as compared with normal rat astrocytes. VEGF expression was depressed by dexamethasone. Expressions of VEGFB mRNA were affected neither by hypoxia nor by dexamethasone. The results indicate a coexpression of VEGF mRNA and VEGFB mRNA in human astrocytomas. Expression of VEGFB is markedly different from that of VEGF. Possible roles of VEGFB as a cofactor for hypoxia-induced angiogenesis in human astrocytomas are discussed.

Alternative Splicing↗
PubMed2000

[Chemotherapy of malignant inoperable gliomas. The association of fotemustine-cisplatine-etoposide as neoadjuvants].

Efficiency of chemotherapy (CT) on non removable HGG has not been proven and neoadjuvant brain irradiation (RT) following biopsy is the standard treatment. We aimed to define whether combination of polychemotherapy and radiotherapy is synergistic in non removable HGG. It has been proven that F, CDDP and VP16 can reach therapeutic levels in brain after intravenous standard dose injections. The aim of this study was to assess that (i) neoadjuvant CT is safe; (ii) feasibility and efficacions of F (100 mg/m2.d1)/CDDP (100 mg/m2.d1-3 TD)/VP16 (75 mg/m2.d1-3) q21-28d regimen; (iii) Delayed RT is not unsafe: RT was performed when tumor progression or toxicity appeared. This study included 16 patients with symptomatic non removable HGG. Two of them had anaplastic gliomas and 14 glioblastomas multiforme. None of them had a prior chemotherapy regimen. Objective response was evaluated with CT scan or MRI during chemotherapy. Toxicity was moderate and mainly hematological (grade III-IV thrombopenia = 10/67 cycles; leukopenia = 13/67). Objective response rates were 5/16 (31 p. 100) (CR = 1; PR = 4; Median duration of response: 20 weeks). Median survival was 55 weeks in the 14 grade IV patients. Three/16 patients are still alived with respectively 22, 30, 40 months survival: These results confirm the neoadjuvant chemotherapy efficacy. It may be a useful tool before RT for non removable HGG.

Adult↗
PubMed2000

[Radiotherapy of high grade glioma: use of fast neutrons, therapy and enhancement by neutron capture].

Among high linear energy transfer (LET) irradiations techniques, those using fast neutrons are able to eradicate glioblastoma cells. At least a 13 grays (Gy) irradiation dose has to be used, but high morbidity is observed in case of over 11 Gy irradiation. So, no therapeutic windows have been found despite the fact that more than 900 patients were included in clinical trials. Boron neutron capture therapy (BNCT) uses alpha emitting nuclear reactions, produced within tumoral cells by boron neutron captures. (10)B is specifically loaded inside tumoral cells via a boronated molecule, and the tissues are then irradiated with thermal or epithermal neutrons. Although this type of irradiation is yet considered as a regular method in Japan, USA and Europe have started clinical trials, currently in progress, in order to define the BNCT place in the post-operative care of high grade glioma. Non-removable tumors may benefit from boron neutron capture enhancement of fast neutron irradiation, i.e. the combination of these two methods. Preliminary studies show that a "biological" dose enhancement of 20 % could be obtained within the tumor when a concentration of 100 microg/g of (10)B is targeted into it. These concentrations are achievable by intra-arterial administration of (10)boronophenylalanine (BPA) or borosulfhydryl (BSH). Recently, some publications have also demonstrated that the thermal neutron flux yielded within the irradiated tissues could be increased. Clinical trials, using this technique, are planned in USA and Europe.

Boron Neutron Capture Therapy↗
PubMed2000

Hypothalamic-pituitary Langerhans cell histiocytosis: a diagnostic challenge.

Four cases of hypothalamic-pituitary Langerhans cell histiocytosis (LCH) are reported, highlighting the expanding spectrum of clinical and magnetic resonance imaging (MRI) features in adults. The diagnostic challenge of hypothalamic-pituitary LCH is emphasized in cases revealed as supra-sellar tumors with panhypopituitarism or as isolated central diabetes insipidus. Diagnosis is confirmed by histological examination showing infiltration with CD1a positive histiocytes. General guidelines for diagnosis procedure are drawn out, including the neurosurgical biopsy in particular cases.

Adult↗
PubMed1999

Beam collimation and bolusing material optimizations for 10boron neutron capture enhancement of fast neutron (BNCEFN): definition of the optimum irradiation technique.

PURPOSE: In boron-10 neutron capture enhancement of fast neutron irradiation (BNCEFN), the dose enhancement is correlated to the 10B concentration and thermal neutron flux. A new irradiation technique is presented to optimize the thermal neutron flux. METHODS AND MATERIALS: The coupled FLUKA and MCNP-4A Monte Carlo codes were used to simulate the neutron production and transport for the Nice and Orleans facilities. RESULTS: The new irradiation technique consists of a 20-cm lead blocks additional collimator, placed close to the patient's head, which is embedded in a pure graphite cube. A 24-fold thermal neutron flux increase is calculated between a 5 x 5 cm2 primary collimated field, with the patient's head in the air, and the same field size irradiated with the optimum irradiation technique. This increase is more important for the p(60)+Be Nice beam than for the p(34)+Be Orleans one. The thermal neutron flux is 2.1 x 10(10) n(th)/Gy for each facility. Assuming a 100 microg/g 10B concentration, a physical dose enhancement of 22% is calculated. Moreover, the thermal neutron flux becomes independent of the field size and the phantom head size. CONCLUSION: This technique allows conformal irradiation of the tumor bed, while the thermal neutron flux is enhanced, and spreads far around the tumor.

Boron Neutron Capture Therapy↗
PubMed1999

Boron neutron capture enhancement (BNCE) of fast neutron irradiation for glioblastoma: increase of thermal neutron flux with heavy material collimation, a theoretical evaluation.

Despite the fact that fast neutron irradiation of glioblastoma has shown on autopsies an ability to sterilize tumors, no therapeutic windows have been found for these particles due to their toxicity toward normal brain. Therefore, the Boron Neutron Capture Enhancement (BNCE) of fast neutron beam has been suggested. This paper addresses the problem of fast neutron beam collimation, which induces a dramatic decrease of the thermal neutron flux in the depth of the tissues when smaller irradiation fields are used. Thermoluminescent dosimeter TLD-600 and TLD-700 were used to determine the thermal neutron flux within a Plexiglas phantom irradiated under the Nice Biomedical Cyclotron p(60)+Be(32) fast neutron beam. A BNCE of 4.6% in physical dose was determined for a 10 x 10 cm2 field, and of 10.4% for a 20 x 20 cm2 one. A Dose Modification Factor of 1.19 was calculated for CAL 58 glioblastoma cells irradiated thanks to the larger field. In order to increase the thermal flux in depth while shaping the beam, heavy material collimation was studied with Monte Carlo simulations using coupled FLUKA and MCNP-4A codes. The use of 20 cm width lead blocks allowed a 2 fold thermal neutron flux increase in the depth of the phantom, while shielding the fast neutron beam with a fast neutron dose transmission of 23%. Using the DMF of 1.19, a BNCE of 40% was calculated in the beam axis. This enhancement might be sufficient to open, at least theoretically, a therapeutic window.

Beryllium↗