Optimizing MR imaging detection of type 2 focal cortical dysplasia: best criteria for clinical practice.

BACKGROUND AND PURPOSE: Type 2 FCD is one of the main causes of drug-resistant partial epilepsy. Its detection by MR imaging has greatly improved surgical outcomes, but it often remains overlooked. Our objective was to determine the prevalence of typical MR imaging criteria for type 2 FCD, to provide a precise MR imaging pattern, and to optimize its detection. MATERIALS AND METHODS: We retrospectively reviewed 1.5T MR imaging of 71 consecutive patients with histologically proved type 2 FCD. The protocol included millimetric 3D T1-weighted, 2D coronal and axial T2-weighted, and 2D or 3D FLAIR images. Two experienced neuroradiologists looked for 6 criteria: cortex thickening, cortical and subcortical signal changes, blurring of the GWM interface, the "transmantle" sign, and gyral abnormalities. The frequency of each sign and their combination were assessed. We compared the delay between epilepsy onset and surgery, taking into account the time of type 2 FCD detection by MR imaging. RESULTS: Only 42 patients (59%) had positive MR imaging findings. In this group, a combination of at least 3 criteria was always found. Subcortical signal changes were constant. Three characteristic signs (cortical thickening, GWM blurring, and transmantle sign) were combined in 64% of patients, indicating that MR imaging can be highly suggestive. However, typical features of type 2 FCD were overlooked on initial imaging in 40% of patients, contributing to a delay in referral for surgical consideration (17 versus 11.5 years when initial MR imaging findings were positive). CONCLUSIONS: A combination of 3 major MR imaging signs allows type 2 FCD to be recognized in clinical practice, thereby enabling early identification of candidates for surgery.

FDG-PET improves surgical outcome in negative MRI Taylor-type focal cortical dysplasias.

OBJECTIVE: To determine the diagnostic accuracy and prognostic value of ¹8FDG-PET in a recent series of patients operated for intractable partial epilepsy associated with histologically proven Taylor-type focal cortical dysplasia (TTFCD) and negative MRI. METHODS: Of 23 consecutive patients (12 male, 7-38 years old) with negative 1.5-Tesla MRI, 10 exhibited subtle nonspecific abnormalities (e.g., unusual sulcus depth or gyral pattern) and the 13 others had strictly normal MRI. FDG-PET was analyzed both visually after coregistration on MRI and using SPM5 software. Metabolic data were compared with the epileptogenic zone (EZ) determined by stereo-EEG (SEEG) and surgical outcome. RESULTS: Visual PET analysis disclosed a focal or regional hypometabolism in 18 cases (78%) corresponding to a single gyrus (n = 9) or a larger cortical region (n = 9). PET/MRI coregistration detected a partially hypometabolic gyrus in 4 additional cases. SPM5 PET analysis (n = 18) was concordant with visual analysis in 13 cases. Location of PET abnormalities was extratemporal in all cases, involving eloquent cortex in 15 (65%). Correlations between SEEG, PET/MRI, and histologic findings (n = 20) demonstrated that single hypometabolic gyri (n = 11) corresponded to EZ and TTFCD, which was localized at the bottom of the sulcus. Larger hypometabolic areas (n = 9) also included the EZ and the dysplastic cortex but were more extensive. Following limited cortical resection (mean follow-up 4 years), seizure freedom without permanent motor deficit was obtained in 20/23 patients (87%). CONCLUSIONS: ¹8FDG-PET coregistered with MRI is highly sensitive to detect TTFCD and greatly improves diagnosis and surgical prognosis of patients with negative MRI.

Diffuse low-grade oligodendrogliomas extend beyond MRI-defined abnormalities.

BACKGROUND: Imaging determinations of the spatial extent of diffuse low-grade gliomas (DLGGs) are of paramount importance in evaluating the risk-to-benefit ratio of surgical resection. However, it is not clear how accurately preoperative conventional MRI can delineate DLGGs. METHODS: We report a retrospective histologic and imaging correlation study in 16 adult patients who underwent serial stereotactic biopsies for the diagnosis of untreated supratentorial well-defined and non-contrast-enhanced DLGG, in whom biopsy samples were taken within and beyond (OutBSs) MRI-defined abnormalities. RESULTS: Thirty-seven OutBSs that extended from 10 to 26 mm beyond MRI-defined abnormalities were studied. Immunostaining revealed MIB-1-positive cells (i.e., cycling cells) in all but 2 of the OutBSs. None of the MIB-1-positive cells coexpressed glial fibrillary acidic protein, and all of them coexpressed OLIG2. MIB-1-positive cells were cycling isolated tumor cells, because 1) their morphologic characteristics reflected those of tumor cells, 2) the number of MIB-1-positive cells per square centimeter was significantly higher than that of controls, 3) the number of MIB-1-positive cells per square centimeter was positively correlated with the tumor growth fraction (p = 0.012), and 4) the number of MIB-1-positive cells per square centimeter in OutBSs decreased with distance from the tumor (p = 0.003). CONCLUSIONS: This study demonstrates, using a multiscale correlative approach, that conventional MRI underestimates the actual spatial extent of diffuse low-grade gliomas (DLGGs), even when they are well delineated. These results suggest that an extended resection of a margin beyond MRI-defined abnormalities, whenever feasible in noneloquent brain areas, might improve the outcome of DLGGs.

[Hypofractionated stereotactic radiotherapy for brain metastases]. / Place de l'irradiation stéréotaxique hypofractionnée dans le traitement des métastases cérébrales.

PURPOSE: A survey of the literature has been performed to find arguments in order to help the choice between radiosurgery and hypofractionated stereotactic radiotherapy in the treatment of brain metastases. PATIENTS AND METHODS: A comparison of two groups of brain metastases treated with hypofractionated stereotactic radiotherapy or radiosurgery, with or without WBRT was performed. Hypofractionated stereotactic radiotherapy: there were eight series including 448 patients published from 2000 to 2009; treated with 5-6 MV X-Rays, non invasive head immobilization, a margin 2 to 10mm; 24 to 40Gy in three to five fractions; a 5 to 8 days duration in six series and 15-16 days in two other series. WBRT (30%) ; radiosurgery: there were 12 series (1994 to 2005) including 2157 patients; an invasive head immobilization, no margin; doses from 10 to 25 Gy; six series over 12 had Gamma Knife radiosurgery and six had Linacs X-Rays. WBRT (30 Gy/10 F/12 days) associated to radiosurgery in several series. The following parameters were compared: median GTV, median survival, 1-year survival rate, local control rate, necrosis and WBRT rates. RESULTS: Hypofractionated stereotactic radiotherapy series: the parameters were respectively: 0,52-4,47 cm(3) (median 2,8 cm(3)); 5-16 months (median 8,7 months); 68,2-93% (median 82,5%); necrosis rate 3,1%; associated WBRT 30%. Radiosurgery series: the parameters were respectively: 1,3 to 5,5 cm(3) (median 2 cm(3)); 5,5 to 22 months (median 11 months); 71 to 95% (median 85%); 0,5 to 6% (median 2,4%); associated WBRT 58%. Results seem similar in the two groups: Hypofractionated stereotactic radiotherapy with non invasive immobilization could theoretically treat all brain metastases sizes except lesions<10 mm (500 mm(3)). In large volumes,>4200 mm(3) GTV, the toxicity of hypofractionated stereotactic radiotherapy was not reported, thus it was difficult to compare its results with the published reports of radiosurgery toxicity. WBRT was a confusing parameter. Obviously, this initial survey has important limitations, specifically its methodology. CONCLUSION: Radiosurgery and hypofractionated stereotactic radiotherapy could be used to treat brain metastases with GTV>500 mm(3) and < or = 4200 mm(3) (Ø 20mm); for GTV<500 mm(3) (Ø 10mm) an invasive procedure with radiosurgery is necessary. For GTV>4200 mm(3) (Ø 20mm), hypofractionated stereotactic radiotherapy could be proposed, provided further studies, using 4 to 6 Gy fractions, a duration less or equal to 10-12 days and a margin of 2mm will be performed.

Transient symptomatic vasospasm following antero-mesial temporal lobectomy for refractory epilepsy.

RATIONALE: Arterial vasospasm has rarely been reported following temporal lobectomy for intractable epilepsy. CASE PRESENTATION: A 31-year-old patient presented with a global aphasia 2 days after a left dominant anteromesial temporal lobectomy for intractable epilepsy. Magnetic resonance imaging on 5th post-operative day revealed severe narrowing of M1 segment of the left middle cerebral artery (MCA) and Transcranial Doppler (TCD) ultrasonography an increased velocity of the MCA that suggested a severe vasospasm. The patient received continuous intravenous hyperhydratation and nimodipine; aphasia improved within 24 h and resolved completely within 6 weeks, associated with velocity reduction on control TCD. CONCLUSION: Transient vasospasm is a likely underestimated cause of focal deficit following temporomesial resection that deserves appropriate treatment.

[Surgical resections in functional areas: report of 89 cases]. / Résections en région fonctionnelle: étude d'une série de 89 cas.

Surgical resections for intractable epilepsy are generally associated with a high risk of permanent neurological deficit and a poor rate of seizure control. We present a series of 89 patients operated on from 1992 through 2007 for drug-resistant partial epilepsy, in whom surgery was performed in a functional area of the brain: the central (sensorimotor and supplementary motor areas) region in 48 cases, posterior regions (parietal and occipital) in 27, the insula in eight, and the language areas in six. Epilepsy was cryptogenic in 12 patients, and lesion-related in 77: malformation of cortical development in 43, tumor in 17, perinatal cicatrix in 13, vascular lesion in three, and another prenatal lesion in one. Seventy patients underwent stereoelectroencephalographic (SEEG) exploration. The surgical procedure was resective (lesionectomy or SEEG-guided corticectomy) in 83 patients and multiple stereotactic thermocoagulations in six. Ten patients were reoperated because of early seizure recurrence. A postoperative complication was observed in 12 patients. Postoperative deficits were observed in 54 patients (61%) and resolved completely in 29. In 25, a permanent deficit persisted, minor in 19 and moderate to severe in six, which did not correlate with localization or etiology. With a one-year follow-up in 74 patients (mean, 3.6 years), 53 (72%) were in Engel's class I, including 38 (51%) in class IA. Seizure outcome was significantly associated with etiology: 93% of Taylor-type focal cortical dysplasia, whereas only 40% of cryptogenic epilepsies were in class I (p<0.05). This suggests that resective or disconnective surgery for intractable partial epilepsy in functional areas of the brain may be followed by excellent results on seizures and a moderate risk of permanent neurological sequelae.

Endovascular coil transfixing a cranial nerve five years after embolisation.

After endovascular coiling, several authors have reported refilling of the aneurysm, appearance of a mass effect, coils protruding into the parent artery, migration of coils into parent artery or through aneurysm wall, and compression of the parent artery by coil impaction. This is the first report of an endovascular coil transfixing a cranial nerve. We present a 59 year old man who presented with a symptomatic bilobulated aneurysm of the right internal carotid artery. The aneurysm was embolised by endovascular coiling. Angiographic follow up showed occlusion of the aneurysm. Five years later, the patient complained of progressive diplopia with ptosis. Follow-up angiography showed renewed filling of the aneurysm at its neck. The aneurysm was clipped surgically. At operation, a coil mass effect was noted and one coil penetrated the fibres of the right oculomotor nerve.

[Vagus nerve stimulation for the treatment of refractory epilepsy]. / Stimulation chronique du nerf vague dans le traitement del'épilepsie pharmacorésistante.

Proposed as an additive symptomatic treatment of refractory epilepsy, vagus nerve stimulation (VNS) has proven to be effective and well-tolerated in patients presenting with refractory epilepsy for whom cortical resection is not indicated. After two years of treatment, the overall reduction of seizure frequency averaged 40%. In 50% of the patients, the frequency of seizures decreased by at least 50%. Moreover, even in absence of a significant reduction of seizures, patients who undergo this treatment reported an improvement in their quality of life. Economic surveys also demonstrate a favorable impact of VNS on the management of refractory epilepsy. Since 1988, 65,000 patients with refractory epilepsy throughout the world have been treated by VNS for this indication (1000 in France). The surgical implantation technique used in our department, the effects of vagus nerve stimulation reported in the literature, and our experience with a cohort of 70 patients with refractory epilepsy who received implants over the last 10 years are described.

Pulsed arterial spin labeling applications in brain tumors: practical review.

Few institutions use MRI perfusion without contrast injection called arterial spins labeling (ASL) routinely in clinical setting. After general considerations concerning the different ASL techniques and quantitative issues, we will detail a pulsed sequence that can be used on a clinical 1.5-T MR unit. We will discuss and illustrate the use of ASL in tumoral diseases for diagnosis, gliomas grading, stereotactic biopsy guidance and for follow-up after treatment.

[Brainstem cavernomas: surgical experience at the CH Sainte-Anne general hospital]. / Cavernomes du tronc cérébral: l'expérience chirurgicale du centre hospitalier Sainte-Anne.

BACKGROUND AND PURPOSE: No standard treatment for brainstem cavernoma has been established because of the lack of sufficient data about the natural history of these lesions in a highly functional location with potential difficult surgical accessibility. METHODS: We present a series of 82 brainstem cavernomas managed at the Sainte-Anne Hospital. Surgery was undertaken for 25 with stereotactic biopsy for 9 and direct surgery for 19 (3 after biopsy). RESULTS: Surgical outcome was good or fair for 17 patients. Two patients worsened and one died. Biopsy results were disappointing with high morbidity (4 patients with 2 permanent deficits). Histological diagnostic was possible for all biopsies. CONCLUSION: In light of these results, an active surgical attitude could be proposed for cavernomas in an accessible locations which have produced at least one previous hemorrhage. Stereotactic biopsies for suspect brainstem cavernoma must be avoided.

[Oligodendrogliomas: historical background of classifications]. / Oligodendrogliomes: historique des classifications.

The story of the classifications for gliomas is related to the development of the techniques used for cytological and histological examination of brain parenchyma. After a review of these techniques and the progressive discovery of the central nervous system cell types, the main classifications are presented. The first classification is due to Bailey and Cushing in 1926. It was based on histoembryogenetic theory. Then Kernohan introduced, in 1938, the concept of anaplasia. The WHO classification was published in 1979, then revised in 1993 and 2000. It took into account some data from both previous systems and introduced gradually the notion of histological criteria of malignancy. More recently; molecular genetics data and clinical evolution were retained. The Sainte-Anne classification for oligodendrogliomas is based on both histological and imaging data. It includes the notion of spatial histological structure of oligodendrogliomas. Contrast enhancement is closely related to endotheliocapillary hyperplasia. Gliomas classifications are changing and confusions can be made because of lack of reproductibility and misinterpretations of samples.

[Spatial delimitation of low grade oligodendrogliomas]. / Délimitation spatiale des oligodendrogliomes de bas grade.

Image-guided surgery is the central element of therapeutic management of low grade gliomas and consequently, a precise preoperative definition of their spatial extension is necessary. The question of the present work is: do the imaging abnormalities delineate the real spatial development of low grade oligodendrogliomas? A review of the literature showed that MRI on T2-weighted and FLAIR sequences are used to delineate the spatial developement of these tumours and that spectroscopic magnetic resonance imaging is more sensible to appreciate it. Moreover, mathematical models and histological studies suggest that MRI does not indicate the actual spatial extension of low grade oligodendrogliomas. This study focused on histological analysis of biopsy samples performed outside MRI imaging abnormalities in patients who harboured a low grade oligodendroglioma. It showed that isolated tumour cells were identified beyond imaging abnormalities in all of the 17 patients studied. In 15 of those 17 patients, isolated tumour cells were identified in the most distant biopsy samples taken outside imaging abnormalities. Thus, conventional imaging findings, including MRI on T2-weighted and FLAIR sequences, are not able to provide the real spatial development and boundaries of low grade oligodendrogliomas.

[Adult supratentorial oligodendrogliomas. Surgical treatment: indications and techniques]. / Oligodendrogliomes supratentoriels de l'adulte. Traitement chirurgical: indications et 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.

[Results of the Sainte-Anne - Lyons series of 318 oligodendroglioma in adults]. / Résultats de la série Sainte-Anne - Lyon de 318 oligodendrogliomes intracrâniens de l'adulte.

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.

Cerebral oligodendrogliomas in adults and children. Current data and perspectives.

Cerebral oligodendrogliomas represent more than 30% of glial tumors in adults. Mean age at diagnosis is 41 for grade A and 45(1/2) for grade B, epilepsy being the main revealing symptom (91.5% of A, 76% of B). Survival at 5, 10 and 15 years is respectively 75.5%, 51% and 22.4% for grade A (median: 136 months), and 45.2%, 31.3% and 0% for grade B (median: 52 months). It is influenced by age at diagnosis: median, before 40 years of age, is 12 years for A and 8(1/2) for B; between 40 and 60, is 12 years for A and 4(1/2) for B; over 60, is 4 years for A and 1(1/2) for B. In children, they represent less than 2.5% of cerebral tumors and include 23% grade A and 77% grade B (48.5% WHO grade II and 51.5% WHO grade III). Mean age at surgical removal is 9.5 +/- 5 years. One third are hemispheric, 2/3 are revealed by epilepsy. A complete surgical removal is performed in 60%. Mean survival is 13 years (154 +/- 20 months), with a mortality at 5 and 10 years of 60% +/- 9%, and a risk of recurrence of 54% +/- 9% at 5 years and 46.5% +/- 10.5% at 5 years. The main differential diagnosis of grade A oligo is dysembryoplastic neuroepithelial tumors (DNT). Inversely, thalamic locations, most often grade B, generally present with a motor deficit; complete removal can be achieved in only 15%. The only efficient treatment is chemotherapy, requiring search for chemosensitivity (1p19q deletion, expression of MGMT gene, analysis by MR-spectroscopy and TEP). Logically, surgical debulking should be as wide as possible, but with preservation of neurological and cognitive functions with the help of modern imaging progresses (fMRI, diffusion and perfusion MRI, tractography, PET) and operative techniques (navigation, cortical stimulation, and even opertaive MRI). Tumors presenting clinical and radiological progression should be removed. Operative mortality varies from 0 to 6%, transient morbidity from 20 to 25%, definit morbidity from 5 to 10%. Radiotherapy does not significantly modify survival whatever the delivered dose. The important point is the patient's radiosensitivity: survival is 148 months for radiosensitive patients versus 12 months for non responsive patients. Studies and development of pretherapeutic assays of tumoral radiosensitivity will be a fundamental research axis (PET, sample studies).

Intraventricular haemorrhage from a renal cell carcinoma pituitary metastasis.

Symptomatic pituitary metastasis and intraventricular haemorrhage from a cerebral metastasis are exceptional events in the natural history of a renal cell carcinoma. We report the first case of a metastatic renal cell carcinoma to the pituitary gland presenting with intraventricular haemorrhage. The origin of intraventricular haemorrhage and its association with renal cell carcinoma pituitary metastasis are discussed.

[Cerebral cavernomas, epilepsy and seizures. Natural history and therapeutic strategy]. / Cavernomes intracrâniens, épilepsie et crises d'épilepsie. Histoire naturelle et modalités thérapeutiques.

PURPOSE: To review, from a retrospective series of 48 patients presenting with seizures associated with one or more supratentorial cavernoma(s), the natural history of the seizures and outcome according to medical and surgical treatment. METHODS: Patients were divided into two groups: group A included patients presenting with a single seizure or rare seizures (n=21), and group B patients having intractable epilepsy (n=27). All received antiepileptic drugs and 35 were operated on (12 in the group A and 23 in the group B). Stereo-EEG was performed in 8 patients in group B. Surgery included lesionectomy alone (n=16), resection of the cavernoma and perilesional tissue (n=7) or tailored corticectomy including the cavernoma (n=12). RESULTS: The natural history of seizures was different in the two groups: mean age at seizure onset was 25 years in group B and 33 years in group A (p<0.05), seizures were partial in all patients in group B and 8 patients in group A (p<0.05). Seizure frequency and periodicity also varied. Prolonged seizure-free periods were observed. The cavernoma was temporal in 17 patients in group B and 4 patients in group A (p<0.01). In group A, seizure outcome was favorable following surgery or with antiepileptic medication only (7 patients out of 12 operated were seizure-free, as were 5 out of 7 non-operated). In group B, seizure outcome was better after surgery than with medication only (17 patients out of 23 operated were in Engel's Class I, while 3 patients of 4 non-operated patients had persisting seizures despite antiepileptic polytherapy). CONCLUSION: Variations in seizure severity in patients harboring cavernomas suggest different therapeutic approaches. In case of unique or rare seizures, surgical resection of the cavernoma is appropriate, but benefits of surgery over antiepileptic medication in terms of seizure control remains unclear. Intractable epilepsy associated with cavernomas is better controlled after surgery rather than with medication only. In these patients, a detailed preoperative work-up is necessary and should be followed by wide resection associated or not with corticectomy, especially in the temporal lobe. Evaluation of outcome after surgery should consider the surgical strategy, antiepileptic medications and the patient's seizure history.

[Adenocarcinomas of the ethmoid sinuses. Epidemiological data]. / Les adénocarcinomes de l'ethmoïde.

OBJECTIVE: The relationship between adenocarcinomas of the ethmoid (ADKE) and wood-dust exposure has been well established. Sino-nasal cancer in wood-workers has been added to the list of occupational disorders in France, as prescribed disease number 47-Bq. PATIENTS AND METHODS: Our data set consisted of 207 cases with sino-nasal cancer (from January 1985 to January 2001). Among these cases, 67.1% were adenocarcinoma. A wood dust exposure has been reported in 96.4% cases. The mean duration of wood dust exposure was 30 years. The mean latency between the end of the exposure and the diagnostic was 10.6 years. RESULTS: Our epidemiological data confirmed those from the biomedical literature. The occupations at greatest risk are furniture workers, sawmill workers, carpentry workers, and other wood product workers. Two components of exposure - duration and average level - contributed independently to the overall elevated risk. The risk is greater among men who were employed in jobs with the highest wood dust exposure and increases with the duration of exposure. CONCLUSIONS: The preinvasive stages of ADKE (mucostasis/cuboïd metaplasia/dysplasia) are still an unverified hypothesis. ADKE were observed in workers who use "hard" woods. The chemical nature of the carcinogenic factor(s) in wood dust is not known. The factors responsible for induction of ADKE in hard wood-workers probably exist in the wood-dust itself. Tannins were suggested as possible contributing agents to induction of ADKE. In addition to wood dust, exposures may include formaldehyde. Given these facts, it should be possible to define preventive measures, so that incidence of ADKE in professional wood and leather workers should decrease.

[The endonasal approach to pituitary adenomas: experience in 105 procedures]. / Intérêt de la voie d'abord endonasale pour l'exérèse des adénomes hypophysaires.

OBJECTIVE: The endonasal approach to the sella turcica is supposed to simplify surgical techniques and reduce the risk and sequelae linked to removal of pituitary adenomas. We report our experience with 105 procedures using this approach. METHOD: The series included 45 men and 60 women, aged 17 to 83 years. Their intrasellar lesions were: 43 non-functional adnomas, 37 prolactinomas, 7 GH- adenomas, 9 corticotrop adenomas, 9 miscellaneous lesions (abscess, Rathke cleft cysts, empty sella). Mean duration of the procedures was 50 minutes. Mean hospital stay was 4 days. RESULTS: There were no deaths. Morbidity included: 1 (0.95%) rhinorrhea associated with meningitis which cured without sequelae, 11 (10.5%) transient diabetes insipidus lasting no longer than 48 hours, 2 cases of permanent diabetes insipidus (1 non-functional macroadenoma, 1 pituitary abscess), 1 transient hyposmia (3 months), 2 transient nasal obstructions. There were no cases of septal perforation, nasal deformation, partial or complete mucosal anesthesia, nasal pain, dental pain, or epistaxis. CONCLUSION: This surgical approach is easier to perform and causes less rhinological sequelae than the sublabial transsphenoidal approach. It allows an as effective tumor removal than the latter. Hospitalization stay is significantly shortened.