Résumé
Giant cell tumors (GCTs) are locally aggressive primary bone tumors of osteoclast-like cells. Most GCTs occur within the long bones, and primary GCTs involving the clivus are extremely rare. We present the case of an 18-year-old boy with binocular horizontal diplopia with an insidious onset who was found to have a hypointense enhancing mass involving the clivus and left side dorsum sellae on magnetic resonance images. The tumor was completely resected via an endoscopic endonasal transclival approach, and histopathologic examination via immunohistochemistry indicated a GCT. The patient’s left abducens nerve palsy improved slightly after surgery. Because of the rarity of GCTs, there is no consensus about the definitive treatment protocol. However, we suggest that gross total resection is the treatment of choice, and denosumab plays a critical role in patients with subtotal resection.
Résumé
Background@#Delayed postoperative hyponatremia (DPH) is the most common cause of readmission after pituitary surgery. In this study, we aimed to evaluate the cutoff values of serum copeptin and determine the optimal timing for copeptin measurement for the prediction of the occurrence of DPH in patients who undergo endoscopic transsphenoidal approach (eTSA) surgery and tumor resection. @*Methods@#This was a prospective observational study of 73 patients who underwent eTSA surgery for pituitary or stalk lesions. Copeptin levels were measured before surgery, 1 hour after extubation, and on postoperative days 1, 2, 7, and 90. @*Results@#Among 73 patients, 23 patients (31.5%) developed DPH. The baseline ratio of copeptin to serum sodium level showed the highest predictive performance (area under the curve [AUROC], 0.699), and its optimal cutoff to maximize Youden’s index was 2.5×10–11, with a sensitivity of 91.3% and negative predictive value of 92.0%. No significant predictors were identified for patients with transient arginine vasopressin (AVP) deficiency. However, for patients without transient AVP deficiency, the copeptin-to-urine osmolarity ratio at baseline demonstrated the highest predictive performance (AUROC, 0.725). An optimal cutoff of 6.5×10–12 maximized Youden’s index, with a sensitivity of 92.9% and a negative predictive value of 94.1%. @*Conclusion@#The occurrence of DPH can be predicted using baseline copeptin and its ratio with serum sodium or urine osmolarity only in patients without transient AVP deficiency after pituitary surgery.
Résumé
Background@#This study aims to elucidate clinical features, therapeutic strategies, and prognosis of pineal parenchymal tumors (PPT) by analyzing a 30-year dataset of a single institution. @*Methods@#We reviewed data from 43 patients diagnosed with PPT at Seoul National UniversityHospital between 1990 and 2020. We performed survival analyses and assessed prognostic factors. @*Results@#The cohort included 10 patients with pineocytoma (PC), 13 with pineal parenchymaltumor of intermediate differentiation (PPTID), and 20 with pineoblastoma (PB). Most patients presented with hydrocephalus at diagnosis. Most patients underwent an endoscopic third ventriculostomy and biopsy, with some undergoing additional resection after diagnosis confirmation. Radiotherapy was administered with a high prevalence of gamma knife radiosurgery for PC and PPTID, and craniospinal irradiation for PB. Chemotherapy was essential in the treatment of grade 3 PPTID and PB. The 5-year progression-free survival rates for PC, grade 2 PPTID, grade 3 PPTID, and PB were 100%, 83.3%, 0%, and 40%, respectively, and the 5-year overall survival rates were 100%, 100%, 40%, and 55%, respectively. High-grade tumor histology was associated with lower survival rates. Significant prognostic factors varied among tumor types, with World Health Organization (WHO) grade and leptomeningeal seeding (LMS) for PPTID, and the extent of resection and LMS for PB. Three patients experienced malignant transformations. @*Conclusion@#This study underscores the prognostic significance of WHO grades in PPT. It is nec-essary to provide specific treatment according to tumor grade. Grade 3 PPTID showed a poor prognosis. Potential LMS and malignant transformations necessitate aggressive multimodal treatment and close-interval screening.
Résumé
Objective@#: Craniopharyngiomas (CPs) are associated with hypothalamic damage that causes hypothalamic obesity, however, the mechanisms underlying CP-related postoperative weight gain remain debatable. This study aimed to elucidate whether the major determinant of postoperative weight gain in patients with CP is hypothalamic injury or steroid replacement therapy. @*Methods@#: We included 48 adult patients with CP (age ≥18 years) who underwent transsphenoidal surgery between 2010 and 2018 in a single tertiary center, and whose body weight was measured pre- and postoperatively (<120 days after the surgery). We recruited 144 age- and body mass index-matched patients with non-functioning pituitary adenoma (NFPA) as controls. @*Results@#: Patients with CP experienced greater postoperative weight gain than patients with NFPA (3.0±5.1 vs. 0.1±3.6 kg, p<0.001). The prevalence of postoperative steroid use was significantly higher in patients with CP than in those with NFPA (89.6% vs. 34.0%, p<0.001). Steroid replacement therapy and CP were associated with postoperative weight gain after adjusting for covariates in overall patients (p=0.032 and 0.007, respectively). In subgroup analysis with postoperative steroid users, weight gain was significantly greater in patients with CP (n=43, 0.96±0.25 kg/month) than in patients with NFPA (n=49, 0.26±0.23 kg/month) even after adjusting for the daily steroid dose (p=0.048). @*Conclusion@#: Patients with CP experience greater postoperative weight gain than those with NFPA. Hypothalamic damage itself as well as steroid replacement may contribute to the postoperative weight gain in patients with CP.
Résumé
Background@#Although long-term dopamine agonist (DA) therapy is recommended as a first-line treatment for prolactinoma, some patients may prefer surgical treatment because of the potential adverse effects of long-term medication, or the desire to become pregnant. This study aimed to determine whether surgical treatment of prolactinomas could be an alternative to DA therapy. @*Methods@#In this retrospective study, 96 consecutive patients (74 female, 22 male) underwent primary pituitary surgery without long-term DA treatment for prolactinomas at a single institution from 1990 to 2010. All patients underwent primary surgical treatment in the microscopic transsphenoidal approach (TSA). @*Results@#The median age and median follow-up period were 31 (16–73) years and 139.1 (12.2–319.6) months, respectively. An initial overall remission was accomplished in 47.9% (46 of 96 patients, 33 macroadenomas, and 13 microadenomas) of patients. DA dose reduction was achieved in all patients after TSA. A better remission rate was independently predicted by lower diagnostic prolactin levels and by a greater extent of surgical resection. Overall remission at the last follow-up was 33.3%, and the overall recurrence rate was 30.4%. The permanent complication rate was 3.1%, and there was no mortality. @*Conclusion@#TSA can be considered a safe and potentially curative treatment for selective microprolactinomas as an alternative to treatment with a long-term DA.
Résumé
Objective@#: The skull base reconstruction step, which prevents cerebrospinal fluid (CSF) leakage, is one of the most challenging steps in endoscopic skull base surgery (ESS). The purpose of this study was to assess the outcomes and complications of a reconstruction technique for immediate CSF leakage repair using multiple onlay grafts following ESS. @*Methods@#: A total of 230 consecutive patients who underwent skull base reconstruction using multiple onlay grafts with fibrin sealant patch (FSP), hydroxyapatite cement (HAC), and pedicled nasoseptal flap (PNF) for high-flow CSF leakage following ESS at three institutions were enrolled. We retrospectively reviewed the medical and radiological records to analyze the preoperative features and postoperative results. @*Results@#: The diagnoses included craniopharyngioma (46.8%), meningioma (34.0%), pituitary adenoma (5.3%), chordoma (1.6%), Rathke’s cleft cyst (1.1%) and others (n=21, 11.2%). The trans-planum/tuberculum approach (94.3%) was the most commonly adapted surgical method, followed by the trans-sellar and transclival approaches. The third ventricle was opened in 78 patients (41.5%). Lumbar CSF drainage was not performed postoperatively in any of the patients. Postoperative CSF leakage occurred in four patients (1.7%) due to technical mistakes and were repaired with the same technique. However, postoperative meningitis occurred in 13.5% (n=31) of the patients, but no microorganisms were identified. The median latency to the diagnosis of meningitis was 8 days (range, 2–38). CSF leakage was the unique risk factor for postoperative meningitis (p<0.001). @*Conclusion@#: The use of multiple onlay grafts with FSP, HAC, and PNF is a reliable reconstruction technique that provides immediate and complete CSF leakage repair and mucosal grafting on the skull base without the need to harvest autologous tissue or perform postoperative CSF diversion. However, postoperative meningitis should be monitored carefully.
Résumé
Background@#Although long-term dopamine agonist (DA) therapy is recommended as a first-line treatment for prolactinoma, some patients may prefer surgical treatment because of the potential adverse effects of long-term medication, or the desire to become pregnant. This study aimed to determine whether surgical treatment of prolactinomas could be an alternative to DA therapy. @*Methods@#In this retrospective study, 96 consecutive patients (74 female, 22 male) underwent primary pituitary surgery without long-term DA treatment for prolactinomas at a single institution from 1990 to 2010. All patients underwent primary surgical treatment in the microscopic transsphenoidal approach (TSA). @*Results@#The median age and median follow-up period were 31 (16–73) years and 139.1 (12.2–319.6) months, respectively. An initial overall remission was accomplished in 47.9% (46 of 96 patients, 33 macroadenomas, and 13 microadenomas) of patients. DA dose reduction was achieved in all patients after TSA. A better remission rate was independently predicted by lower diagnostic prolactin levels and by a greater extent of surgical resection. Overall remission at the last follow-up was 33.3%, and the overall recurrence rate was 30.4%. The permanent complication rate was 3.1%, and there was no mortality. @*Conclusion@#TSA can be considered a safe and potentially curative treatment for selective microprolactinomas as an alternative to treatment with a long-term DA.
Résumé
Objective@#: The skull base reconstruction step, which prevents cerebrospinal fluid (CSF) leakage, is one of the most challenging steps in endoscopic skull base surgery (ESS). The purpose of this study was to assess the outcomes and complications of a reconstruction technique for immediate CSF leakage repair using multiple onlay grafts following ESS. @*Methods@#: A total of 230 consecutive patients who underwent skull base reconstruction using multiple onlay grafts with fibrin sealant patch (FSP), hydroxyapatite cement (HAC), and pedicled nasoseptal flap (PNF) for high-flow CSF leakage following ESS at three institutions were enrolled. We retrospectively reviewed the medical and radiological records to analyze the preoperative features and postoperative results. @*Results@#: The diagnoses included craniopharyngioma (46.8%), meningioma (34.0%), pituitary adenoma (5.3%), chordoma (1.6%), Rathke’s cleft cyst (1.1%) and others (n=21, 11.2%). The trans-planum/tuberculum approach (94.3%) was the most commonly adapted surgical method, followed by the trans-sellar and transclival approaches. The third ventricle was opened in 78 patients (41.5%). Lumbar CSF drainage was not performed postoperatively in any of the patients. Postoperative CSF leakage occurred in four patients (1.7%) due to technical mistakes and were repaired with the same technique. However, postoperative meningitis occurred in 13.5% (n=31) of the patients, but no microorganisms were identified. The median latency to the diagnosis of meningitis was 8 days (range, 2–38). CSF leakage was the unique risk factor for postoperative meningitis (p<0.001). @*Conclusion@#: The use of multiple onlay grafts with FSP, HAC, and PNF is a reliable reconstruction technique that provides immediate and complete CSF leakage repair and mucosal grafting on the skull base without the need to harvest autologous tissue or perform postoperative CSF diversion. However, postoperative meningitis should be monitored carefully.
Résumé
Objective@#: Metaplastic meningioma is an extremely rare subtype of World Health Organization (WHO) grade I meningioma. It has distinctive histological subtypes according to its own mesenchymal components. Owing to its scarcity, clinical or radiological features of a metaplastic meningioma are poorly described. @*Methods@#: Between 2004 and 2018, we analyzed total 1814 cases surgically proven meningioma for 15 years. Among them, metaplastic meningioma was diagnosed in 11 cases. Magnetic resonance images were taken for all patients, and computed tomography scan was taken for 10 patients. @*Results@#: WHO grade I meningiomas were 1376 cases (75.9%), 354 cases (19.5%) in WHO grade II, and 84 cases (4.6%) in WHO grade III meningiomas. Metaplastic meningioma was 11 cases as 0.8% of WHO grade I meningioma and 0.6% of entire meningiomas for 15 years. Among the entire 11 metaplastic meningiomas, five tumors (45%) were diagnosed as a lipomatous subtype with rich fat components, four (36%) as an osseous subtype with extensive bone formation and two (18%) as a xanthomatous subtype. There was no cartilaginous subtype metaplastic meningioma in our study. Lipomatous and osseous metaplastic meningioma have peculiar radiological characteristics according to mesenchymal components. @*Conclusion@#: We investigated a rare metaplastic meningioma subtype based on our 15-year surgical experience with meningiomas.Further investigation will be necessary for the clear clarification of tumor nature of this rare tumor.
Résumé
Idiopathic granulomatous hypophysitis (IGH), a rare disease, requires differentiation from more common mass lesions of the sella such as pituitary adenoma, craniopharyngioma, Rathke's cleft cyst, or pituitary tuberculoma. IGH usually presents with an insidious onset of visual defects and headaches. On the other hand, rapid onset of neurologic and visual symptoms in an IGH patient is exceptionally rare. Here, we present a biopsy-proven case of IGH with rapid onset and satisfactory outcome after high dose steroid treatment.
Sujets)
Adulte , Humains , Hypophysite auto-immune , Craniopharyngiome , Endoscopie , Glucocorticoïdes , Main , Céphalée , Hypophyse , Tumeurs de l'hypophyse , Maladies rares , Selle turcique , TuberculomeRésumé
BACKGROUND: Invasive nonfunctioning pituitary adenomas (NFPAs) remain challenging due to their high complication rate and poor prognosis. We aimed to identify the distinctive molecular signatures of invasive NFPAs, compared with noninvasive NFPAs, using gene expression profiling by RNA sequencing. METHODS: We obtained frozen fresh tissue samples from 14 patients with NFPAs who underwent primary transsphenoidal surgery. Three non-invasive and 11 invasive NFPAs were used for RNA sequencing. The bioinformatics analysis included differential gene expression, gene ontology analysis, and pathway analysis. RESULTS: A total of 700 genes were differentially expressed (59 up-regulated and 641 down-regulated genes) between invasive and non-invasive NFPAs (false discovery rate <0.1, and |fold change| ≥2). Using the down-regulated genes in invasive NFPAs, gene ontology enrichment analyses and pathway analyses demonstrated that the local immune response was attenuated and that transforming growth factor-β (TGF-β) RII-initiated TGF-β signaling was down-regulated in invasive NFPAs. The overexpression of claudin-9 (CLDN9) and the down-regulation of insulin-like growth factor-binding protein 5 (IGFBP5), death-associated protein kinase 1 (DAPK1), and tissue inhibitor of metalloproteinase-3 (TIMP3) may be related with invasiveness in NFPAs. CONCLUSION: Invasive NFPAs harbor different gene expression profiles relative to noninvasive NFPAs. In particular, local suppression of the immune response and TGF-β signaling can make PAs prone to invasiveness.
Sujets)
Humains , Biologie informatique , Death-associated protein kinases , Régulation négative , Expression des gènes , Analyse de profil d'expression de gènes , Gene Ontology , Tumeurs de l'hypophyse , Pronostic , Analyse de séquence d'ARN , Inhibiteur tissulaire de métalloprotéinase-3 , TranscriptomeRésumé
The hypoglossal nerve (CN XII) may be placed at risk during posterior fossa surgeries. The use of intraoperative monitoring (IOM), including the utilization of spontaneous and triggered electromyography (EMG), from tongue muscles innervated by CN XII has been used to reduce these risks. However, there were few reports regarding the intraoperative transcranial motor evoked potential (MEP) of hypoglossal nerve from the tongue muscles. For this reason, we report here two cases of intraoperative hypoglossal MEP monitoring in brain surgery as an indicator of hypoglossal deficits. Although the amplitude of the MEP was reduced in both patients, only in the case 1 whose MEP was disappeared demonstrated the neurological deficits of the hypoglossal nerve. Therefore, the disappearance of the hypoglossal MEP recorded from the tongue, could be considered a predictor of the postoperative hypoglossal nerve deficits.
Sujets)
Humains , Encéphale , Électromyographie , Potentiels évoqués moteurs , Nerf hypoglosse , Tumeurs sous-tentorielles , Surveillance peropératoire , Muscles , LangueRésumé
The endoscopic endonasal approach (EEA) has been popularized in adults and has been applied to an expanding range of surgical modules and indications in this population. However, its clinical application in pediatric neurosurgery has been impeded by the differences in anatomical features and the relatively low incidence of diseases to which it is applicable. In this review article, we mainly discuss the surgical indications, feasibility, and complications of EEA for suprasellar lesions in children based on a review of the literature, focusing especially on the age-related anatomical features of the nasal cavity, various pathologic entities, and the impact of EEA on long-term craniofacial growth.
Sujets)
Adulte , Enfant , Humains , Incidence , Fosse nasale , NeurochirurgieRésumé
PURPOSE: Homeobox (HOX) genes are essential developmental regulators that should normally be in the silenced state in an adult brain. The aberrant expression of HOX genes has been associated with the prognosis of many cancer types, including glioblastoma (GBM). This study examined the identity and role of HOX genes affecting GBM prognosis and treatment resistance. MATERIALS AND METHODS: The full series of HOX genes of five pairs of initial and recurrent human GBM samples were screened by microarray analysis to determine the most plausible candidate responsible for GBM prognosis. Another 20 newly diagnosed GBM samples were used for prognostic validation. In vitro experiments were performed to confirm the role of HOX in treatment resistance. Mediators involved in HOX gene regulation were searched using differentially expressed gene analysis, gene set enrichment tests, and network analysis. RESULTS: The underexpression of HOXA11 was identified as a consistent signature for a poor prognosis among the HOX genes. The overall survival of the GBM patients indicated a significantly favorable prognosis in patients with high HOXA11 expression (31±15.3 months) compared to the prognoses in thosewith low HOXA11 expression (18±7.3 months, p=0.03). When HOXA11 was suppressed in the GBM cell lines, the anticancer effect of radiotherapy and/or temozolomide declined. In addition, five candidate mediators (TGFBR2, CRIM1, TXNIP, DPYSL2, and CRMP1) that may confer an oncologic effect after HOXA11 suppression were identified. CONCLUSION: The treatment resistance induced by the underexpression of HOXA11 can contribute to a poor prognosis in GBM. Further investigation will be needed to confirm the value of HOXA11 as a potential target for overcoming the treatment resistance by developing chemo- or radiosensitizers.
Sujets)
Adulte , Humains , Encéphale , Lignée cellulaire , Gènes homéotiques , Glioblastome , Techniques in vitro , Analyse sur microréseau , Pronostic , RadiothérapieRésumé
The small pituitary mass was incidentally found in 40-years-old women with renal cell carcinoma. The endocrinological and ophthalmological evaluation revealed no deficit and the short-term follow-up was recommended. In 6 months later, the visual disturbance was reported and the size of mass was increased. The tumor was removed totally via the trans-sphenoid approach. The post-operative endocrinological insufficiency was not noticed. During one year of follow-up period, there was no evidence of recurrence without adjuvant radiotherapy. The clinical features of pituitary metastasis from renal cell carcinoma were similar to those of pituitary adenoma. The possibility of pituitary metastasis should be kept in mind in patients with sellar mass and renal cell carcinoma.
Sujets)
Femelle , Humains , Néphrocarcinome , Diagnostic différentiel , Études de suivi , Métastase tumorale , Tumeurs de l'hypophyse , Radiothérapie adjuvante , RécidiveRésumé
OBJECTIVE: The surgical approach for recurrent pituitary adenoma after trans-sphenoidal approach (TSA) is challenging. We report the outcomes of the endoscopic TSA for recurrent pituitary adenoma after microscopic TSA. METHODS: From February 2010 to February 2013, endoscopic TSA was performed for removal of 30 recurrent pituitary adenomas after microscopic TSA. Twenty-seven (90%) patients had a clinically non-functioning pituitary adenoma. Twenty-four (80%) patients suffered from a visual disturbance related to tumor growth. The clinical features and surgical outcomes were retrospectively analyzed for the ophthalmological, endocrinological, and oncological aspects. RESULTS: The mean tumor volume was 11.7 cm3, and gross total resection was achieved in 50% of patients. The volumetric analysis based on the postoperative MR showed that the mean extent of resection rates were 90%. Vision was improved in 19 (79%) of 24 patients with visual symptoms, and endocrinological cure was achieved in all of three functioning pituitary adenomas; however, the post-operative follow-up endocrinological examination revealed a new endocrinological deficit in one patient. Two patients required antibiotics management for post-operative meningitis. CONCLUSION: The endoscopic TSA can be an effective treatment option for recurrent pituitary adenoma after microscopic TSA with acceptable outcome.
Sujets)
Humains , Antibactériens , Endoscopie , Études de suivi , Tumeurs de l'hypophyse , Études rétrospectives , Charge tumorale , VisionRésumé
OBJECTIVE: This retrospective study was performed to evaluate the role of chemotherapy in the management of patients with anaplastic astrocytoma (AA). METHODS: We compared the survival outcome among the 3 different treatment protocol groups in a single institution. A total of 86 patients (39 men and 47 women) with newly diagnosed AA after surgery were analyzed. Among them, 31 patients (36.0%) were treated with radiotherapy only (RT Group), 30 patients (34.9%) were treated with nimustine-cisplatin chemotherapy before RT (ACNU-CDDP group), and 25 patients (29.1%) were treated with procarbazine, lomustine and vincristine (PCV) chemotherapy after radiotherapy (PCV group). RESULTS: The median survival was 14.0, 30.0 and 72.0 months in RT, ACNU-CDDP, and PCV group, respectively and showed significant differences (RT vs. ACNU-CDDP; p=0.039, RT vs. PCV; 0.002, ACNU-CDDP vs. PCV; 0.045). PCV group showed less toxicity rate (5 patients; 20%) than ACNU-CDDP group (12 patients; 40%), while only 3 patients (9.6%) in RT group experienced grade 3 or 4 toxicities. CONCLUSION: An application of chemotherapy before or after radiotherapy is beneficial in prolonging the survival of patients with AA. Adjuvant PCV chemotherapy after radiotherapy is recommendable.
Sujets)
Humains , Mâle , Astrocytome , Protocoles cliniques , Lomustine , Procarbazine , Études rétrospectives , VincristineRésumé
OBJECTIVE: This retrospective study was performed to evaluate the role of chemotherapy in the management of patients with anaplastic astrocytoma (AA). METHODS: We compared the survival outcome among the 3 different treatment protocol groups in a single institution. A total of 86 patients (39 men and 47 women) with newly diagnosed AA after surgery were analyzed. Among them, 31 patients (36.0%) were treated with radiotherapy only (RT Group), 30 patients (34.9%) were treated with nimustine-cisplatin chemotherapy before RT (ACNU-CDDP group), and 25 patients (29.1%) were treated with procarbazine, lomustine and vincristine (PCV) chemotherapy after radiotherapy (PCV group). RESULTS: The median survival was 14.0, 30.0 and 72.0 months in RT, ACNU-CDDP, and PCV group, respectively and showed significant differences (RT vs. ACNU-CDDP; p=0.039, RT vs. PCV; 0.002, ACNU-CDDP vs. PCV; 0.045). PCV group showed less toxicity rate (5 patients; 20%) than ACNU-CDDP group (12 patients; 40%), while only 3 patients (9.6%) in RT group experienced grade 3 or 4 toxicities. CONCLUSION: An application of chemotherapy before or after radiotherapy is beneficial in prolonging the survival of patients with AA. Adjuvant PCV chemotherapy after radiotherapy is recommendable.
Sujets)
Humains , Mâle , Astrocytome , Protocoles cliniques , Lomustine , Procarbazine , Études rétrospectives , VincristineRésumé
Ewing's sarcoma/primitive neuroectodermal tumor (ES/PNET) is an unusual malignancy with aggressive behavior. ES/PNET in the cerebellopontine angle (CPA) is extremely uncommon, and we report on a rare case here. A 31-year-old man presented with one month history of left facial palsy, hearing loss, swallowing difficulty, and hoarseness. Magnetic resonance images showed a large mass in the left CPA and a small one in the right cerebellar hemisphere. The patient underwent a surgery for the CPA mass lesion, and the pathology was compatible with ES/PNET. Radiation therapy and chemotherapy were administered. In contrast to the initial radiologic findings resembling vestibular schwannoma or meningioma, ES/PNET had several distinct clinical features. A patient with a CPA mass and presenting unusual clinical features should be suspected of having a rare malignancy.
Sujets)
Adulte , Humains , Angle pontocérébelleux , Déglutition , Paralysie faciale , Perte d'audition , Enrouement , Spectroscopie par résonance magnétique , Méningiome , Tumeurs neuroectodermiques , Tumeurs neuroectodermiques primitives , Neurinome de l'acoustique , Sarcome d'EwingRésumé
OBJECTIVE: We analyzed the methylation status of the O6-methylguanine-DNA methyltransferase (MGMT) gene promoter in World Health Organization (WHO) grade III gliomas in association with other molecular markers to evaluate their prevalence. METHODS: The samples of a total of 36 newly WHO grade III glioma patients including 19 anaplastic oligodendrogliomas (AO), 7 anaplastic oligoastrocytomas (AOA), and 10 anaplastic astrocytomas (AA) were analyzed. The methylation status of the MGMT gene promoter was confirmed by methylation-specific polymerase chain reaction. The 1p/19q chromosomal deletion status and EGFR amplification were assessed by Fluorescence In-Situ Hybridization. MGMT, EGFR, EGFRvIII, and p53 expression were analyzed by immunohistochemical staining. RESULTS: The MGMT gene promoter was methylated in 32 (88.9%) and unmethylated in 4 (11.2%). Among them, all of the AO and AOA had methylated MGMT gene promoter without exception. Significant associations between MGMT gene promoter hypermethylation and 1p/19q deletion was observed (p = 0.003). Other molecular markers failed to show significant associations between MGMT gene promoter statuses. CONCLUSION: There was extensive epigenetic silencing of MGMT gene in high grade gliomas with oligodendroglial component. Together with frequent 1p/19q co-deletion in oligodendroglial tumors, this may add plausible explanations supporting the relative favorable prognosis in oligodendroglial tumors compared with pure astrocytic tumors.