[Contribution of temozolomide chemotherapy for intramedullary grade II spinal cord astrocytomas in adults: Our experience]. / Place de la chimiothérapie de type témozolomide pour les astrocytomes intramédullaires de grade II de l'adulte : notre expérience.

INTRODUCTION: Grade II intramedullary astrocytomas are rare tumors. Despite a well-defined role of adjuvant temozolomide chemotherapy for brain gliomas, the contribution of this therapy for intramedullary gliomas is not yet clearly defined. METHOD: We retrospectively analyzed the data of 5 adult patients treated with temozolomide between 2008 and 2015 for a grade II intramedullary astrocytoma with progression after surgery. RESULTS: Five patients from 19 to 70 years of age (median, 37years) underwent a second surgery for the progression of a grade II intramedullary astrocytoma (median progression-free survival 26months [8-90]). All tumors remained grade II. Due to a second clinical or/and radiological tumor progression, the patients were treated with temozolomide after a 37months median progression-free survival (5-66). All patients received at minimum 12 cycles (mean 14 ± 5; range 12-24) of temozolomide (150-200mg/m2/day, 5days/28days). All patients were alive after a 10-year median follow-up after diagnosis (6-13). All patients were able to walk except one, who was previously in McCormick autonomy grade IV before chemotherapy. The McCormick autonomy rating after temozolomide was stable for 4 patients and improved for 1 patient. The treatment was delayed once for hematological toxicity. CONCLUSION: Temozolomide stabilized all 5 patients without any major toxicity. Based on this experience that needs to be confirmed, we consider that temozolomide should be envisaged within the therapeutic arsenal for progressive intramedullary grade II astrocytomas.

[Supraorbital approach to treat a fronto-orbital fracture with pneumocephaly, a minimal invasive technique]. / Abord supraorbitaire pour traiter une fracture frontale avec pneumocéphalie, une technique peu invasive.

We describe a supraorbital approach through an upper eyebrow skin incision to treat a fronto-orbital fracture with pneumocephaly in a 84-year-old cardiac patient. The clinical and cosmetic results are excellent. This case is illustrated by pre- and postoperative CT-scan and MRI as well as pictures showing the minimal invasive technique.

An observational study of the first experience with bevacizumab for the treatment of patients with recurrent high-grade glioma in two belgian university hospitals.

Background. Bevacizumab (BEV), a humanized immunoglobulin G1 monoclonal antibody that inhibits VEGF has demonstrated activity against recurrent high-grade gliomas (HGG) in phase II clinical trials. Patients and Methods. Data were collected from patients with recurrent HGG who initiated treatment with BEV outside a clinical trial protocol at two Belgian university hospitals. Results. 19 patients (11 M/8 F) were administered a total of 138 cycles of BEV (median 4, range 1-31). Tumor response assessment by MRI was available for 15 patients; 2 complete responses and 3 partial responses for an objective response rate of 26% for the intent to treat population were observed on gadolinium-enhanced T1-weighted images; significant regressions on T2/FLAIR were documented in 10 out of 15 patients (67%). A reduced uptake on PET was documented in 3 out of 4 evaluable patients. The six-month progression-free survival was 21% (95% CI 2.7-39.5). Two patients had an ongoing tumor response and remained free from progression after 12 months of BEV treatment. Conclusions. The activity and tolerability of BEV were comparable to results from previous prospective phase II trials. Reduced uptake on PET suggests a metabolic response in addition to an antiangiogenic effect in some cases with favorable clinical outcome.

[Long-term outcome of patients treated with spinal cord stimulation for therapeutically refractory failed back surgery syndrome: a retrospective study]. / Évaluation à long terme de la stimulation médullaire dans les douleurs lombosciatiques neuropathiques postopératoires: étude rétrospective.

BACKGROUND AND PURPOSE: Long-term efficiency (>5 years) of spinal cord stimulation for failed back surgery syndrome is poorly described in literature. The aims of our study were to evaluate the long-term efficiency and the quality of life of our series of patients with spinal cord stimulation for failed back surgery syndrome. METHODS: The data of 55 patients implanted successively in our institution between 1995 and 2005 for failed back surgery syndrome were collected retrospectively. We contacted them for a telephone survey focused on efficiency, quality of life and treatment satisfaction. RESULTS: An internal pulse generator was placed in 42 patients. Thirty-two of them were contacted to answer our survey with a mean follow-up of 8.3 years. Seventy-five percent of our population reported a pain decrease of greater or equal to 50%. The efficiency of percutaneous leads was reported as 50% for the quadripolars and 83% for the octopolars. The surgical leads evaluations were positive in 70% for 4 × 1 as well as for 4 × 2 leads. We observed a default of low back pain relief in 84% of patients with an incomplete pain relief (59%). The ability to sit, get out of the bed, and climb stairs increased in 75%. The walk was better in 82%. Decrease in drug consumption of greater or equal to 50% was observed in 66%. CONCLUSIONS: Our retrospective study demonstrates a satisfaction of 75% of the patients after 8.3-years follow-up. Spinal cord stimulation is an effective treatment for refractory failed back surgery syndrome.

Minimally invasive endoscopic unilateral transsphenoidal surgery for pituitary adenomas.

OBJECTIVE: The aim of this study was to analyse the results of minimally invasive endoscopic unilateral transsphenoidal surgery for pituitary adenomas. METHODS: A series of 83 patients presenting with a pituitary lesion was reviewed retrospectively. Surgical procedures were performed between February 2007 and December 2010. The extent of resection was evaluated on post-operative contrast-enhanced MRI. We also reviewed our complications and compared them with the literature. RESULTS: Our series included 10 micro- and 73 macro-adenomas, with cavernous sinus invasion in 60.3%. Fifty-three per cent were non-secreting. Complete resection of the macro-adenomas was achieved in 22.5% of the cases. Complications were as follows: 2 deaths (2.5%), 2 sinusitis (2.5%), 5 CSF leaks (6.2%), 1 meningitis (1.2%), 16 post-operative anterior lobe insufficiency (19.8%) and 4 persistent diabetes insipidus (4.9%). Thirty-seven patients (44.6%) presented with a compression of optical pathways with an improvement of visual acuity in 94.3%. CONCLUSIONS: Purely endoscopic unilateral endonasal transsphenoidal adenoma resection is minimally invasive surgery leading to a good rate of gross total tumour resection and it is associated with a low complication rate.

The role of interventional neuroradiology in the management of skull base tumours and related surgical complications.

The management of hypervascular skull base tumours is complex and requires a multidisciplinary approach. Skull base surgery may be challenging because of the risk of serious intra-operative bleeding and of potential injuries to lower cranial nerves and/or large cervical vessels. Over the last four decades, advances in neuro-interventional procedures have produced a range of adjunctive endovascular techniques in addition to conventional surgery. Digital subtraction angiography (DSA) allows for a better understanding of tumour vascularisation and its relationship with Surrounding vessels. Tumoural devascularisation and the occlusion of feeding arteries is a useful adjunct to surgery because it allows for the reduction of intra-operative blood loss and induces ischaemic necrosis of the tumour. Finally, surgery-related iatrogenic vascular lesions may be successfully treated with endovascular techniques. Nevertheless, endovascular procedures in the head and neck region are associated with infrequent but potentially serious complications. An extensive and comprehensive knowledge of head and neck vascular anatomy is therefore necessary. This article provides a review of the indications for, and results of, diagnostic, pre-operative and therapeutic endovascular procedures for the management of skull base tumours and related surgical complications.

Hearing outcome after gamma knife radiosurgery for vestibular schwannoma: a prospective Belgian clinical study.

INTRODUCTION: Leksel Gamma Knife (LGK) radiosurgery is a safe and efficient therapeutic approach for vestibular schwannoma (VS) with low side effects. The goal of radiosurgery is not necessarily to cause significant tumour necrosis or to obtain a complete radiographic response, but to halt the tumour's growth permanently through its biological elimination. The 2 major aims of radiosurgery for VS are long-term tumour control and functional hearing preservation. The purpose of this study is to report our experience with LGK radiosurgery in the management of VS and to evaluate the hearing preservation rate after a minimum one-year follow-up. MATERIAL AND METHODS: Between January 2000 and January 2011, 415 patients with unilateral VS underwent LGK radiosurgery at the University Erasmus Hospital of Brussels. There were 349 patients with previously untreated VS (86 grade I, 96 grade II, 141 grade III, 9 grade IVa, 17 unknown grades, according to Koos) and 66 patients with post-operative residual tumour. All patients in our series underwent evaluation with high resolution neurodiagnostic imaging including computed tomography and magnetic resonance imaging, and clinical evaluation as well as audiological tests that included tonal and speech audiometries. The Gardner Robertson (GR) classification is used to report the results of this study. We identified 276 patients treated for VS with LGK, tested and retested with speech and tonal audiometries by the same team, and followed for a minimum of one year. RESULTS: Before LGK, 144 patients had serviceable (85 GR class I and 59 GR class II) hearing; 95 (65.97%) of these patients had preservation of serviceable hearing (Pure tone average < or = 50 db and Speech discrimination > or = 50%) at minimum one-year audiological follow-up. It was observed that 44 of the 85 GR class I patients (51.76%) maintained their level of audition and 66 of these (74.64%) preserved serviceable hearing. In the 34 patients with preradiosurgery non-serviceable hearing (GR class III-IV) 25 of these patients (73.52%) maintained their hearing. The tumour was stable or declining in size in 90.44% of cases. CONCLUSION: LGK radiosurgery provides excellent tumour control in vestibular schwannomas and has low toxicity even after long-term follow-up.

[Non-functioning pituitary adenoma: is there an interest to treat a residue after surgery?]. / Adénome hypophysaire non sécrétant: faut-il traiter un résidu après chirurgie?

Diagnosis of non-functioning pituitary adenoma is generally posted when there is a compression of the ophthalmic nerve or when a hypopituitarism occurred. Surgery will be the first treatment but complete removal can be achieved in less than 50% of the patients. In the great majority of the patients, there is a recurrence and a new treatment is proposed. The question is when we must treat a residue after surgery. We performed a retrospective study reviewing a series of 111 patients with a non-functioning pituitary adenoma. All patients had a pre- and post-operative MRI (1.5 T). A statistical analysis was done to determine the influence of the resection, the age of the patient on the recurrence. A complete removal was achieved for 45 patients and 11 of these present a recurrence. 39 patients out of 66 patients who had a partial removal presented also a recurrence. The mean age of the population is 53 years. The statistical analysis demonstrates that patients with a complete removal had less recurrence. Patient with an age below 60 years had more frequently a recurrence compared with older than 60 years old. In conclusion, treatment for non-functioning pituitary adenoma is a transsphenoidal approach surgery. A complete surgery must be the aim of the neurosurgeon. And when a residue is present, a secondary treatment must be given for patient with an age below 60 years old like radiosurgery or radiation therapy.

Solitaire stent for endovascular treatment of intracranial aneurysms: immediate and mid-term results in 15 patients with 17 aneurysms.

INTRODUCTION: The Solitaire stent is the first fully retractable stent for endovascular treatment (EVT) of intracranial aneurysms. The aim of this study was to evaluate its use in a prospective series with mid-term follow-up. METHODS: A retrospective review of our prospectively maintained database identified all patients treated with a Solitaire stent. Clinical charts, procedural data, angiographic results were reviewed. RESULTS: Between June 2008 and September 2009, 15 patients with 17 wide-necked or fusiform aneurysms (16 unruptured/one ruptured) were identified. EVT was successfully performed in all but one patient in whom the stent was removed because it induced flow reduction in the 1.8-mm parent artery. Among 14 treated patients, 13 had an excellent outcome and one had a good outcome. In this latter patient, the first stent could not be delivered and was changed for another one that was successfully deployed. The patient experienced a thrombo-embolic complication 6 hours after EVT and kept a slight hand paresis. In all cases but one, the stent was thus easily navigated and positioned despite a relative poor visibility. Angiographic results included eight complete occlusions, two neck remnants, and six incomplete occlusions. Six-month control in 14 aneurysms showed 13 complete occlusions and one incomplete occlusion. CONCLUSION: The Solitaire stent is useful for EVT of complex intracranial aneurysms because it is fully retractable, easy to navigate and to precisely place. However, it should be used with caution in arteries less than 2mm in diameter.

Endovascular treatment of anterior choroidal artery aneurysms.

INTRODUCTION: Endovascular treatment (EVT) of anterior choroidal artery aneurysms (AChAA) may be challenging because of the close relationship with the parent artery. The aim of this study was to report our experience with EVT of AChAA. METHODS: A retrospective review of our prospectively maintained database identified all AChAA treated by embolization. The clinical charts, procedural data and angiographic results were reviewed. RESULTS: From April 2004-August 2008, 11 patients were identified. Five patients presented with a subarachnoid hemorrhage (SAH) and six patients were asymptomatic. Aneurysms size varied from two to 13 mm (mean size=3.6 mm) and nine had an unfavourable neck/sac ratio (>or=0.7). The anterior choroidal artery was arising from the sac (n=6) or from the neck (n=5). Endovascular treatment consisted of balloon-assisted coiling (n=8), coiling (n=2) and stent-assisted coiling (n=1). No procedural complication occurred and all patients had an excellent outcome except one patient who died because of severe vasospasm 8 days after an uneventful EVT. Immediate angiographic control showed six complete occlusions, one neck remnant and four incomplete occlusions. Follow-up controls (mean=18 months) were obtained in eight patients and showed five stable occlusions and three further thrombosis achieving complete occlusion. CONCLUSION: EVT of AChAA is associated with very good clinical and long-term anatomical results. Because of their small size, unfavourable neck/sac ratio and close relationship with the parent artery, EVT frequently requires the use of adjunctive techniques such as balloon or stent-assisted coiling.

The prognostic value of health-related quality-of-life data in predicting survival in glioblastoma cancer patients: results from an international randomised phase III EORTC Brain Tumour and Radiation Oncology Groups, and NCIC Clinical Trials Group study.

This is one of the few studies that have explored the value of baseline symptoms and health-related quality of life (HRQOL) in predicting survival in brain cancer patients. Baseline HRQOL scores (from the EORTC QLQ-C30 and the Brain Cancer Module (BN 20)) were examined in 490 newly diagnosed glioblastoma cancer patients for the relationship with overall survival by using Cox proportional hazards regression models. Refined techniques as the bootstrap re-sampling procedure and the computation of C-indexes and R(2)-coefficients were used to try and validate the model. Classical analysis controlled for major clinical prognostic factors selected cognitive functioning (P=0.0001), global health status (P=0.0055) and social functioning (P<0.0001) as statistically significant prognostic factors of survival. However, several issues question the validity of these findings. C-indexes and R(2)-coefficients, which are measures of the predictive ability of the models, did not exhibit major improvements when adding selected or all HRQOL scores to clinical factors. While classical techniques lead to positive results, more refined analyses suggest that baseline HRQOL scores add relatively little to clinical factors to predict survival. These results may have implications for future use of HRQOL as a prognostic factor in cancer patients.

[Management of low-grade glioma: a retrospective study concerning 201 patients]. / Prise en charge des gliomes de bas grade: série rétrospective de 201 patients.

BACKGROUND AND PURPOSE: Optimal treatment for low-grade glioma remains controversial. Moreover, though surgery is recommended for disease management, evidence is lacking concerning the appropriate extent of surgery and the use of adjunctive therapy. Available data is basically retrospective, coming from series with substantial limitations. We reviewed our institution's series in order to evaluate the efficiency of surgical management and the influence of the extent of surgical removal for patients with low-grade glioma. METHODS: Data were collected from a series of 201 patients who underwent first-intention therapy for low-grade glioma, the standard practice in our institution between 1994 and 2005. After applying certain exclusion criteria, we retained for analysis 123 patients with grade II glioma (WHO classification). We compared progression-free survival curves for the three surgical treatment groups defined as biopsy, partial removal, or total removal. RESULTS: Statistical evaluation of the progression free survival shows a benefit in total surgery as a first intention treatment. No statistical significance was demonstrated between partial surgery and stereotactic biopsy. CONCLUSION: For patients with low-grade glioma we recommend total surgical removal as first intention management.

Long-term efficacy of early versus delayed radiotherapy for low-grade astrocytoma and oligodendroglioma in adults: the EORTC 22845 randomised trial.

BACKGROUND: Postoperative policies of "wait-and-see" and radiotherapy for low-grade glioma are poorly defined. A trial in the mid 1980s established the radiation dose. In 1986 the EORTC Radiotherapy and Brain Tumor Groups initiated a prospective trial to compare early radiotherapy with delayed radiotherapy. An interim analysis has been reported. We now present the long-term results. METHODS: After surgery, patients from 24 centres across Europe were randomly assigned to either early radiotherapy of 54 Gy in fractions of 1.8 Gy or deferred radiotherapy until the time of progression (control group). Patients with low-grade astrocytoma, oligodendroglioma, mixed oligoastrocytoma, and incompletely resected pilocytic astrocytoma, with a WHO performance status 0-2 were eligible. Analysis was by intention to treat, and primary endpoints were overall and progression-free survival. FINDINGS: 157 patients were assigned early radiotherapy, and 157 control. Median progression-free survival was 5.3 years in the early radiotherapy group and 3.4 years in the control group (hazard ratio 0.59, 95% CI 0.45-0.77; p<0.0001). However, overall survival was similar between groups: median survival in the radiotherapy group was 7.4 years compared with 7.2 years in the control group (hazard ratio 0.97, 95% CI 0.71-1.34; p=0.872). In the control group, 65% of patients received radiotherapy at progression. At 1 year, seizures were better controlled in the early radiotherapy group. INTERPRETATION: Early radiotherapy after surgery lengthens the period without progression but does not affect overall survival. Because quality of life was not studied, it is not known whether time to progression reflects clinical deterioration. Radiotherapy could be deferred for patients with low-grade glioma who are in a good condition, provided they are carefully monitored.

Oesophageal perforation by an anterior cervical fixation device: management in debilitated patients.

Oesophageal perforation following anterior cervical fixation has been reported in the neurosurgical and orthopaedic literature as a rare complication of such procedure. The complications associated with oesophageal perforation may range from minor symptoms to mediastinitis and death. We report two oesophageal perforations following cervical fixation device migration in patients with poor prognosis, managed successfully with conservative surgical and endoscopic techniques.

[Transsphenoidal approach with low field MRI for pituitary adenoma]. / Apport de la résonance magnétique per-opératoire à bas champs dans la chirurgie de l'adénome hypophysaire.

INTRODUCTION: Appropriate evaluation of resection remains one of the major difficulties of surgical treatment of pituitary adenoma. The transsphenoidal approach does not allow direct visual control. Endoscopy provides useful information but may no distinguish well residual adenoma from the pituitary gland. Intraoperative MRI offers new perspectives for assessing the quality of resection. We report our experience with low field intraoperative MRI in surgical treatment of pituitary adenoma. POPULATION: Intraoperative MRI (Polestar N10, 30 patients and Polestar N20, 17 patients) was performed in 45 consecutive patients undergoing surgery for pituitary adenoma. Thirty-seven patients had a macroadenoma. Patients were in the prone position with the head fixed with a three-pin MRI-compatible headholder. METHOD: Coronal T1 MRI scans with enhancement were acquired pre and per operatively. We compared scans and surgical filling (complete removal). If there was a difference, a surgical control was undertaken. RESULTS: Intraoperative images were unavailable for two patients due to small size of the neck and the pituitary glands which were not in the middle in the field of view. For the others, the pituitary glands were in the field of view and the intraoperative scans could be used for comparison. For four patients, there was a discrepancy between surgeon filling and the intraoperative MRI. A control showed no residual adenoma but hemostatic tissue. CONCLUSION: Low field intraoperative MRI is an excellent technique for controlling the size of pituitary adenoma resection.

[Contribution of PET to the management of patients with low-grade glioma]. / Apport de la tomographie à émission de positons dans la prise en charge des gliomes de bas grade.

BACKGROUND AND PURPOSE: Management of patients with low-grade glioma is a major challenge for the neurosurgeon. When is neurosurgery indicated? Should chemotherapy or radiotherapy be used? Many questions without an answer. We reviewed our experience with 65 patients treated for low-grade glioma who had preoperative PET images (FDG or/and MET). We examined the prognostic value of PET and also determined the sensitivity and the specificity of PET images to predict outcome. METHODS: Sixty-five patients with a FDG or MET PET images were analyzed. We used two visual scales and had complete follow-up data for 63 patients. The free interval was the principal criterion for statistical analysis. The sensitivity and the specificity of PET images was determined. RESULTS: Strong FDG uptake was correlated with a short free interval (p=0.001). Similar results were found with the MET analysis (p=0.0076). We had a PET with MET and FDG for 36 patients. The sensitivity was 66% and the specificity 94% for FDG PET. Sensitivity was 100% and specificity 53% for MET PET. CONCLUSIONS: PET imaging provides a prognostic factor independent from histology. MET PET is the best exam for the follow-up of patients with low-grade glioma and is helpful for separating aggressive from low-grade glioma.

S100A5: a marker of recurrence in WHO grade I meningiomas.

Some WHO grade I intracranial meningiomas resected from the same sites and with the same quality of resection (Simpson's grading scale) recur, while others do not. The reasons for this variability in occurrence of recurrence have not yet been determined. We therefore investigated the prognostic recurrence value of seven biological markers on a series of completely resected WHO grade I meningiomas. For this purpose, we analysed a series of 33 WHO grade I meningiomas totally resected between 1980 and 1990 (a follow-up of 10 years), including 14 cases of recurrence. The fixed tumour material from each meningioma was submitted to histochemical analyses targeting galectin-3 and its binding sites, the S100A5, S100A6 and S100B proteins, and cathepsin-B and -D. The levels of expression were assessed semi-quantitatively (in terms of the staining intensity and the labelling index) and submitted to uni- and multivariate analyses. Of all the markers investigated, only S100A5 expression can be associated with any significant prognostic value in the matter of recurrence. More particularly, the meningiomas with high levels of S100A5 staining intensity either did not recur, or recurred later than those with a low immunopositive S100A5 intensity (P = 0.004). Cox regression analyses demonstrated that this latter marker was associated with significant prognostic values independent of the patients' ages. Furthermore, the combination of the patients' ages and S100A5 staining intensity permitted the identification of a group with a particularly high risk of recurrence, that is, the patients younger than 55 and with meningiomas exhibiting low S100A5 intensities (P = 0.001). In conclusion, the S100A5 protein could play a role in the recurrence of totally resected WHO grade I meningiomas.

[Pineal region surgery. Experience in 22 patients]. / La chirurgie de la région épiphysaire. Expérience de 22 cas.

BACKGROUND AND PURPOSE: Different approaches to the pineal region are described in the literature with high mortality and morbidity. We report our experience with two different approaches (occipitoparietal or infratentorial supracerebellar approaches) for pineal region. METHODS: Between 1986 and 1997, 25 operations were performed in 22 patients. Preoperative work-up included a CT-scan with conventional angiography (for older patients), magnetic resonance imaging with angiographic study (angio-MRI) for the others. Two different approaches, the occipitoparietal (n=14) or the infratentorial supracerebellar (n=8) ones, were used. Three patients had a stereotactic biopsy, followed by a total resection for one of them. RESULTS: The mortality and morbidity induced by the approaches were low compared to the series of the literature. Only 2 patients were worsened by the surgery: Patient 4 developed hemianopsia after an occipitoparietal approach and patient 21 temporary Parinaud syndrome after resection of a teratoma by supracerebellar infratentorial approach. One patient improved his neurological status but died on the 10th postoperative day from pulmonary embolism. CONCLUSIONS: Total or partial resection of well-defined pineal region lesions by direct neurosurgical approaches can be achieved in most cases with low morbidity. The choice among the two surgical occipitoparietal or infratentorial supracerebellar approaches depends on the size and the location of the lesion in the pineal area, its relation to the ventricular system, the median line and the splenium. Angiographic sequences in magnetic resonance with study of the deep veins are helpful in this respect.

[The neurosurgery department]. / Le Service de Neurochirurgie.

Opened on November 1st, 2001, the Department of Neurosurgery has progressively grown to become worldwide renown in a few years. All the pathologies are covered, from lumbar disc hernia to intracranial tumors and vascular malformations. But the originality stays into the exceptional environment by the concentration of logistic resources and the ability of clinician and researchers who daily collaborate with the neurosurgical team. The Department of Neurosurgery has a strong reputation in several fields like intraspinal cord tumors or Pet-guided Neurosurgery in stereotactic biopsies, neuronavigation and Gamma Knife and, generally speaking, in the original approach of the treatment and follow-up of brain tumors. Neurodegenerative diseases also benefit of modern approaches trough the Gamma Knife, deep brain stimulation or fetal cell grafting into the brain in Parkinson and soon in Huntington diseases. Last but not least, the arrival for the 25th anniversary of Erasme Hospital of an interventional MRI will allow to follow in real-time the resection of brain tumors with an obvious benefit for the surgical performances and the quality of life of the patients. It will also open a new window for neurosurgical research through combination with functional MRI and Pet-Scan, reinforcing the reputation of Erasme Neurosurgical Department who has been distinguished in 1997 by the World Health Organisation as "WHO Collaborating Center for Research and Training in Neurosurgery" and nominated again in 2002 for a new 4-year period, which is unique in the Neurosurgical World.

Positron emission tomography with injection of methionine as a prognostic factor in glioma.

OBJECT: Positron emission tomography with L-[methyl-11C]methionine (MET-PET) provides information on the metabolism of gliomas. The aim of this study was to determine the predictive value of MET-PET in the treatment of patients with gliomas. METHODS: Since 1992, 85 patients with a World Health Organization (WHO) classification-verified glioma underwent PET studies in which MET was injected before (74 cases) or after treatment (11 cases). Analysis of PET data was conducted by the same investigator using two scales: a qualitative visual grading scale and a quantitative scale (ratio between tumor uptake and normal brain uptake, classified on a seven-level scale). Uptake of MET was present in 98% of gliomas. The investigator judged this uptake to be moderate to very high based on visual inspection (qualitative scale). For all grades of gliomas, a visual grade of 3 was statistically associated with a shorter patient survival period (p < 0.005). The tumor/normal brain uptake ratio was significantly influenced by the histological grade of the tumor. A statistically poor outcome was demonstrated when this ratio was higher than a threshold of 2.2 for a WHO Grade II tumor and 2.8 for WHO Grade III tumor. For Grade II and III tumors, oligodendrogliomas had a higher uptake of MET than astrocytomas. CONCLUSIONS: Uptake of MET was present in 98% of the gliomas studied. A high uptake is statistically associated with a poor survival time. The intensity of MET uptake represents a prognostic factor for WHO Grade II and III tumors considered separately.