Clinical and imaging characteristics of supratentorial glioma with IDH2 mutation.

PURPOSE: The rarity of IDH2 mutations in supratentorial gliomas has led to gaps in understanding their radiological characteristics, potentially resulting in misdiagnosis based solely on negative IDH1 immunohistochemical staining. We aimed to investigate the clinical and imaging characteristics of IDH2-mutant gliomas. METHODS: We analyzed imaging data from adult patients with pathologically confirmed diffuse lower-grade gliomas and known IDH1/2 alteration and 1p/19q codeletion statuses obtained from the records of our institute (January 2011 to August 2022, Cohort 1) and The Cancer Imaging Archive (TCIA, Cohort 2). Two radiologists evaluated clinical information and radiological findings using standardized methods. Furthermore, we compared the data for IDH2-mutant and IDH-wildtype gliomas. Multivariate logistic regression was used to identify the predictors of IDH2 mutation status, and receiver operating characteristic curve analysis was employed to assess the predictive performance of the model. RESULTS: Of the 20 IDH2-mutant supratentorial gliomas, 95% were in the frontal lobes, with 75% classified as oligodendrogliomas. Age and the T2-FLAIR discordance were independent predictors of IDH2 mutations. Receiver operating characteristic curve analysis for the model using age and T2-FLAIR discordance demonstrated a strong potential for discriminating between IDH2-mutant and IDH-wildtype gliomas, with an area under the curve of 0.96 (95% CI, 0.91-0.98, P = .02). CONCLUSION: A high frequency of oligodendrogliomas with 1p/19q codeletion was observed in IDH2-mutated gliomas. Younger age and the presence of the T2-FLAIR discordance were associated with IDH2 mutations and these findings may help with precise diagnoses and treatment decisions in clinical practice.

Paediatric supratentorial tumours do not cause microstructural alterations in contralateral white matter: a preliminary study.

BACKGROUND AND PURPOSE: Intracranial tumours in children can exhibit different characteristics compared to those in adults. Understanding the microstructural changes in the contralateral normal-appearing white matter (NAWM) in children with primary intracranial masses is essential for optimizing treatment strategies. This study aimed to investigate the apparent diffusion coefficient (ADC) changes in contralateral NAWM using fully automated methods and deep learning algorithms. METHODS: We included 22 paediatric patients with primary supratentorial intracranial masses (23% high-grade) in the study. ADC values of the contralateral NAWM in the patient group were compared to those of a control group. Deep learning algorithms were utilized to analyse diffusion changes in NAWM. RESULTS: The mean ADC values of contralateral NAWM in the patient group were 0.80 ± 0.03 × 10-3 mm2/s, while the control group had a mean ADC value of 0.81 ± 0.03 × 10-3 mm2/s. There was no statistically significant difference between the groups (p = 0.39). Our findings indicate that there are no significant diffusion changes in the contralateral white matter of children with supratentorial intracranial masses. CONCLUSION: Primary supratentorial intracranial masses in children do not cause microstructural changes in contralateral normal-appearing white matter. This could be attributed to the less infiltrative nature and different biochemical profile of these tumour groups in the paediatric population. Further studies using advanced imaging techniques could provide additional insights into the distinct characteristics of paediatric intracranial tumours and improve patient management.

[Supratentorial neuroepithelial tumor with PLAGL1 gene fusion - a new type of morphologically variable pediatric brain neoplasm defined by a distinct DNA methylation class. A case report and literature review]. / Supratentorial'naya neiroepitelial'naya opukhol' so sliyaniem gena PLAGL1 u detei ­ novyi tip opukholi mozga s raznoobraznoi morfologicheskoi kartinoi i otlichitel'nym metilyatsionnym profilem(sluchai iz praktiki i obzor literatury).

BACKGROUND: Methylation analysis has become a powerful diagnostic tool in modern neurooncology. This technique is valuable to diagnose new brain tumor types. OBJECTIVE: To describe the MRI and histological pattern of neuroepithelial tumor with PLAGL1 gene fusion. MATERIAL AND METHODS: We present a 6-year-old patient with small right frontal intraaxial tumor causing drug resistant epilepsy. Despite indolent preoperative clinical course and MRI features suggesting glioneuronal tumor, histological evaluation revealed characteristics of high-grade glioma, ependymoma and neuroblastoma. RESULTS: Methylation analysis of tumor DNA confirmed a new type of a recently discovered neoplasm - neuroepithelial tumor with PLAGL1 fusion (NET PLAGL1). PCR confirmed fusion of PLAGL1 and EWSR1 genes. No seizures were observed throughout the follow-up period. There was no tumor relapse a year after surgery. CONCLUSION: Methylation analysis in neurooncology is essential for unclear tumor morphology or divergence between histological and clinical data. In our case, this technique confirmed benign nature of tumor, and we preferred follow-up without unnecessary adjuvant treatment.

A unique case of intracranial collision tumor composed of ganglioglioma WHO gr I and supratentorial ependymoma WHO gr III: case-based literature review.

PURPOSE: Intracranial collision tumor is a rare entity that represents the coexistence of two histopathological different tumor types in the same area without histological admixture or an intermediate cell population zone. So far, several cases of collision tumors with ganglioglioma as its component have been reported in the literature, while supratentorial ependymoma has never been reported as a collision tumor component. We are presenting a unique case of collision tumor in patient without previous history of head trauma, neurological surgery, radiotherapy, or phakomatosis. METHODS AND RESULTS: A 17-year-old male with no previous history of head trauma, neurological surgery, radiotherapy, or phakomatosis was presented to our clinic with grand mal seizure. Brain magnetic resonance imaging with gadolinium contrast was done revealing a contrast-enhancing lesion of right frontal lobe closely related to dura, surrounded by perifocal edema. The patient underwent a gross total tumor resection. Histological examination revealed collision tumor with two distinct components: ganglioglioma and supratentorial ependymoma. CONCLUSION: To our best knowledge, no previous reports of collision tumor composed of ganglioglioma and supratentorial ependymoma in a single patient have been reported. We believe that this report could significantly contribute to further surgical practice as well as to treatment decision for these types of collision tumors.

Differentiation between supratentorial pilocytic astrocytoma and extraventricular ependymoma using multiparametric MRI.

BACKGROUND: The differentiation of supratentorial pilocytic astrocytomas (STPAs) and supratentorial extraventricular ependymomas (STEEs) is clinically pivotal because of distinct therapeutic management and prognosis, which is sometimes challenging to both neuroradiologists and pathologists. PURPOSE: To explore and compare the conventional and advanced magnetic resonance imaging (MRI) features between STPA and STEE. MATERIAL AND METHODS: A total of 23 patients with STPAs and 23 patients with STEEs were reviewed in this study. All patients performed conventional MRI, susceptibility-weighted imaging (SWI), and diffusion-weighted imaging (DWI), and 34 patients (17 with STPAs and 17 with STEEs) examined dynamic susceptibility contrast-enhanced perfusion-weighted imaging (DSC-PWI) in addition. Clinical data, conventional MRI features, minimum relative apparent diffusion coefficient ratio (rADCmin), and maximum relative cerebral blood volume ratio (rCBVmax) were compared between the two groups and subgroups. The optimal cutoff values of rADCmin and rCBVmax with sensitivity and specificity were calculated. RESULTS: STPA manifested similar to STEE as a solid-cystic mass but more frequently presented with a marked enhancing deep nodule (P = 0.02), no peritumoral edema (P = 0.036), higher rADCmin value (2.0 ± 0.5 vs. 0.9 ± 0.2; P < 0.001), and lower rCBVmax value (2.1 ± 0.4 vs. 14.4 ± 5.5; P < 0.001). The cutoff value of >1.39 for rADCmin and ≤ 2.81 for rCBVmax produced a high sensitivity of 95.65% and 100.0%, respectively, and all produced a specificity of 100.0% in differentiating STPAs from STEEs. CONCLUSION: Multiparametric MRI techniques including conventional MRI, DWI, and DSC-PWI contribute to the differential diagnosis of STPA and STEE.

Advanced MRI shape analysis as a predictor of histologically aggressive supratentorial meningioma.

BACKGROUND AND PURPOSE: A subset of aggressive meningioma is associated with higher morbidity and requires a different therapeutic management. This subset consists of World Health Organization (WHO) grade II and III meningioma, characterized particularly with microscopic brain invasion. Numerous studies tried to screen aggressive meningioma on pre-operative MRI. The objective of the study was to determine if an advanced shape analysis of supratentorial meningioma outlines could reliably predict WHO II-III grade and histological brain invasion. MATERIALS AND METHODS: We performed a retrospective analysis for all consecutive patients who underwent surgery for supratentorial histologically-proven meningioma from 2010 to 2018. Pre-operative MRI T1WI contrast enhanced axial, coronal and sagittal slices were collected from 101 patients. Advanced shape analysis including fractal analysis and topological skeleton analysis was performed. Shape analysis parameters were correlated with histopathological WHO grading and brain invasion on surgical pieces. RESULTS: Shape analysis features such as a low circularity, a low solidity, a high fractal dimension and a high number of skeleton's branches were significantly correlated with both WHO II-III meningioma and histological brain invasion. Cross-validated regression models including these features were predictive of WHO II-III meningioma and brain invasion with respective AUC of 0.71 and 0.72. CONCLUSIONS: MRI shape analysis provides informative imaging biomarkers to predict high WHO grade and histological brain invasion of supratentorial meningioma. Further prospective studies including the evaluation of a fully-automatized and totally reproducible process are required to confirm the results.

Supratentorial Extraventricular Ependymomas: Imaging Features and the Added Value of Apparent Diffusion Coefficient.

OBJECTIVE: To improve the understanding and the diagnosis of intracranial ependymal tumors. METHODS: The clinical, radiological and prognostic features of 48 supratentorial extraventricular ependymomas and 74 intraventricular ependymomas were summarized and compared. RESULTS: Supratentorial extraventricular ependymomas, most often located in the frontal lobe (33.3%) and classified as grade III (75.0%), had relatively large eccentric cysts (3.07 ± 2.03 cm), significant enhancement (84.8%), low apparent diffusion coefficient (ADC) values, and associated with higher mortality (41.3%). The majority of intraventricular lesions occurred in the fourth ventricle (86.5%) and classified as grade II (78.4%), had relatively small and multiple cystic changes (1.04 ± 0.87 cm), slight or moderate enhancement (76.9%), high ADC values and associated with lower mortality (20.7%). There were few significant differences between grade II and grade III tumors in these 2 groups, respectively. Young age, high grade and low ADC values are worse prognostic indicators for patients with supratentorial extraventricular ependymomas, but not for those with intraventricular ependymomas. CONCLUSIONS: Conventional radiological features, combined with clinical manifestations and quantitative information provided by diffusion-weighted imaging, may not only enhance the diagnosis and assist in determining prognosis but also provide a better pathophysiological understanding of intracranial ependymal tumors.

The clinical and imaging features of infratentorial germinomas compared with supratentorial ectopic germinomas.

BACKGROUND: Intracranial germinoma is very sensitive to chemoradiotherapy, while the risk of infratentorial operation is high. The accurate diagnosis can provide the more reasonable treatment, avoiding the unnecessary therapeutic risks. PURPOSE: To evaluate the clinical and imaging features of infratentorial germinomas. MATERIAL AND METHODS: The clinical and imaging data of 13 infratentorial germinomas were collected and compared with 17 supratentorial germinomas in the same period. The clinical and imaging findings were retrospectively analyzed. RESULTS: Infratentorial germinomas were more common in female patients than supratentorial ones (53.85% vs. 11.76%, P = 0.020). The mean age of the infratentorial group (23.0 ± 10.2 years) was significantly older than that of supratentorial group (12.4 ± 3.3 years, P = 0.003). Most infratentorial germinomas (12/13, 92.31%) underwent surgical resection, while stereotactic biopsy was more common in the supratentorial group (11/17, 64.71%, P = 0.002). Infratentorial germinomas were significantly smaller than supratentorial ones (25.85 ± 8.13 mm vs. 37.18 ± 18.11 mm, P = 0.031). Cystic lesions were more common in supratentorial germinomas (12/17, 70.59%), while most infratentorial germinomas were solid lesions (10/13, 76.92%, P = 0.025). On post-contrast T1-weighted imaging, obvious enhancement was more common in infratentorial germinomas than in supratentorial ones (100% vs. 64.71%, P = 0.024). CONCLUSION: In addition to the common findings with supratentorial germinomas, infratentorial lesions have some specific clinical and imaging features.

Supratentorial pediatric cortical ependymomas: a comprehensive retrospective study.

Pediatric cortical ependymomas (CEs) are rare; the clinical features and optimal treatment remain ill-defined. We aimed to clarify the clinical characteristics and outcome of pediatric CEs based on institutional series and literature review. Thirteen children with CEs from our department were included in the present study. Furthermore, a search of English language peer-reviewed articles yielded 43 patients with CEs. The clinical data, treatment, and outcome were retrospectively reviewed and statistically analyzed. Our institutional series consisted of nine males and four females. The literature review yielded 56 pediatric CE cases (including ours) for further analysis. Of these 56 cases, frontal lobe (n = 19, 41.3%) was the most common location and most of the tumors were located in the right hemisphere (n = 27, 58.7%). Seizures (n = 23, 41.1%) were the most frequent preoperative symptoms. Thirty patients (n = 30, 53.6%) were WHO grade II. Five continuous patients in our series screened for C11orf95-RELA fusion and all the patients (100%) were RELA fusion positive. Fourteen (26.4%) patients experienced tumor recurrence and 4 (7.5%) patients died during the follow-up. Multivariate survival analysis depicted extent of surgery resection was the only prognostic factor for PFS and patient with gross total resection (P = 0.037, HR 3.682, 95% CI 1.082-13.79) had longer PFS. Furthermore, Log-rank testing for Kaplan-Meier survival analysis showed the extent of surgery resection (P = 0.007) was the only prognostic factor for OS. Pediatric CEs are rare, commonly seen in frontal lobe and right hemisphere. Seizures are the most common symptoms. They may have higher rate of RELA fusions, but favorable outcome. A low incidence of anaplastic histology has been depicted. Gross total resection is significantly associated with longer PFS and OS. Careful follow-up is necessary because the tumors may progress.

Minimally invasive trans-sulcal parafascicular surgical resection of cerebral tumors: translating anatomy to early clinical experience.

The minimally invasive port-based trans-sulcal parafascicular surgical corridor (TPSC) has incrementally evolved to provide a safe, feasible, and effective alternative to access subcortical and intraventricular pathologies. A detailed anatomical foundation is important in mitigating cortical and white matter tract injury with this corridor. Thus, the aims of this study are (1) to provide a detailed anatomical construct and overview of TPSCs and (2) to translate an anatomical framework to early clinical experience. Based on regional anatomical constraints, suitable parafascicular entry points were identified and described. Fiber tracts at both minimal and increased risks for each corridor were analyzed. TPSC-managed cases for metastatic or primary brain tumors were retrospectively reviewed. Adult patients 18 years or older with Karnofsky Performance Status (KPS) ≥ 70 were included. Subcortical brain metastases between 2 and 6 cm or primary brain tumors between 2 and 5 cm were included. Patient-specific corridors and trajectories were determined using MRI-tractography. Anatomy: The following TPSCs were described and translated to clinical practice: superior frontal, inferior frontal, inferior temporal, intraparietal, and postcentral sulci. Clinical: Eleven patients (5 males, 6 females) were included (mean age = 52 years). Seven tumors were metastatic, and 4 were primary. Gross total, near total, and subtotal resection was achieved in 7, 3, and 1 patient(s), respectively. Three patients developed intraoperative complications; all recovered from their intraoperative deficits and returned to baseline in 30 days. A detailed TPSC anatomical framework is critical in conducting safe and effective port-based surgical access. This review may represent one of the few early translational TPSC studies bridging anatomical data to clinical subcortical and intraventricular surgical practice.

Intraparenchymal supratentorial papillary meningioma: a case report.

Although intraparenchymal meningiomas have rarely been reported in the literature, the papillary type has been reported only as infratentorial. Here we report the case of a 21-year-old female patient with intraparenchymal lesion. To our knowledge, this case describes the first report of a patient with a supratentorial intraparenchymal papillary meningioma.

Conventional and Advanced Magnetic Resonance Imaging Features of Supratentorial Extraventricular Ependymomas.

OBJECTIVE: To describe the magnetic resonance imaging characteristics of supratentorial ependymomas. METHODS: The magnetic resonance imaging and computed tomography imaging characteristics of 49 cases of supratentorial ependymomas were analyzed retrospectively. The location, size, degree of perilesional edema, gross appearance, computed tomography attenuation characteristics, T1 and T2 signal intensity characteristics, degree of diffusion restriction, presence of calcification, and hemorrhage were documented for each lesion. The intratumoral susceptibility scores (ITSS), apparent diffusion coefficient (ADC) values, relative cerebral blood volume, and choline/N-acetyl aspartate ratios were documented where available. RESULTS: The frontal lobe was the most common location with a mean size of 6.37 × 4.8 cm. Severe perilesional edema was evident in 30%. Heterogenous, solid-cystic appearance was present in 96% lesions, with 95% of extraventricular lesions extending from pial surface to the ventricular margin. Calcification was seen in 55% of cases. The ITSS was 3 in 85.7% of lesions. The mean ADC value calculated was 600 × 10 mm/s. The mean relative cerebral blood volume on dynamic susceptibility contrast perfusion was 4.83. The mean choline/N-acetyl aspartate ratio was 5.87. Leptomeningeal dissemination was demonstrable in 5 lesions. Four lesions were abutting the dura with frank dural invasion in one. One patient presented with disseminated disease without evidence of a primary lesion. CONCLUSIONS: A large lesion with relatively well-defined margins, heterogeneous solid cystic appearance, extending from the pial surface to the ventricular margin, presence of calcification, and ADC values approaching those of white matter should raise a suspicion of supratentorial ependymoma. High ITSS, MR perfusion parameters, and magnetic resonance spectroscopy characteristics are similar to those of other high-grade gliomas.

Influence of wide opening of the lateral ventricle on survival for supratentorial glioblastoma patients with radiotherapy and concomitant temozolomide-based chemotherapy.

The prognosis for glioblastoma (GBM) varies among patients. Ventricular opening during surgery has been reported as a prognostic factor for GBM patients, but the influence of ventricular opening itself on patient prognosis remains controversial. We presumed that the degree of ventricular opening would correlate with the degree of subventricular zone (SVZ) resection and with prognosis in GBM patients. This study therefore investigated whether the degree of ventricular opening correlates with prognosis in GBM patients treated with the standard protocol of chemo-radiotherapy. Participants comprised 111 patients with newly diagnosed GBM who underwent surgery and received postoperative radiotherapy and temozolomide-based chemotherapy from 2005 to 2018. We classified 111 patients into "No ventricular opening (NVO)", "Ventricular opening, small (VOS; distance < 23.2 mm)", and "Ventricular opening, wide (VOW; distance ≥ 23.2 mm)" groups. We evaluated the relationship between degree of ventricular opening and prognosis using survival analyses that included other clinicopathological factors. Log-rank testing revealed age, Karnofsky performance status (KPS), extent of resection, O6-methylguanine-DNA methyltransferase (MGMT) status, isocitrate dehydrogenase (IDH)1 mutation, and degree of ventricular opening correlated significantly with overall survival. Multivariate analysis identified the degree of ventricular opening (small vs. wide) as the most significant prognostic factor (hazard ratio = 3.674; p < 0.0001). We demonstrated that wide opening of the lateral ventricle (LV) contributes to longer survival compared with small opening among GBM patients. Our results indicate that wide opening of the LV may correlate with the removal of a larger proportion of tumor stem cells from the SVZ.

Investigating dynamic susceptibility contrast-enhanced perfusion-weighted magnetic resonance imaging in posterior fossa tumors: differences and similarities with supratentorial tumors.

PURPOSE: To assess the accuracy of dynamic susceptibility contrast-enhanced perfusion-weighted magnetic resonance imaging in glioma grading and brain tumor characterization of infratentorial tumors, and to investigate differences from supratentorial tumors. METHODS: This retrospective study, approved by the institutional review board, included 246 patients with brain tumors (184 supratentorial, 62 infratentorial), grouped by tumor type: high-grade gliomas (HGG), low-grade gliomas (LGG), metastases (Met), and primary central nervous system lymphoma (PCNSL). Relative cerebral blood volume (rCBV) and mean percentage of signal recovery (PSR) were calculated. For statistical analyses, lesions were grouped by location and histology. Differences were tested with Mann-Whitney U tests. From ROC curves, we calculated accuracy, sensitivity, specificity, PPV, and NPV, for rCBV and PSR. RESULTS: For infratentorial tumors, rCBV was highly accurate in differentiating HGG from LGG (AUC = 0.938). Mean PSR showed high accuracy in differentiating PCNSL and HGG from Met (AUC = 0.978 and AUC = 0.881, respectively). Infratentorial and supratentorial tumors had similarly high rCBV in HGG, high mean PSR in PCNSL, and low mean PSR in Met. The main differences were the optimum threshold rCBV values (3.04 for supratentorial, 1.77 for infratentorial tumors) and the mean PSR, which was significantly higher in LGG than in HGG in supratentorial (p = 0.035), but not infratentorial gliomas. Using infratentorial rCBV threshold values for supratentorial tumors decreased the sensitivity and specificity. CONCLUSION: rCBV and mean PSR were useful in grading and differentiating infratentorial tumors. Proper cutoff values were important in the accuracy of perfusion-weighted imaging in posterior fossa tumors.

[Comparative analysis of mono- and bipolar pyramidal tract mapping in patients with supratentorial tumors adjacent to motor areas: comparison of data at 64 stimulation points]. / Sravnitel'nyi analiz potochechnogo mono- i bipolyarnogo kartirovaniya piramidnogo trakta u patsientov s supratentorial'nymi opukholyami, prilezhashchimi k motornym zonam golovnogo mozga: sravnenie dannykh v 64 tochkakh stimulyatsii.

OBJECTIVE: To compare monopolar and bipolar mapping in point-by-point fashion by using of threshold amperage, frequency of positive motor responses and the number of muscles involved in response. MATERIAL AND METHODS: A prospective non-randomized study included 14 patients with supratentorial tumors who underwent surgery in 2018-2019. All neoplasms were localized within 2 cm from the motor cortex and pyramidal tract. Age of patients ranged from 25 to 74 years. There were 9 women and 5 men. Eight patients had malignant glioma (grade III - 4, grade IV - 4), 6 patients - meningioma. Motor functions were assessed in all patients before and after surgery (1, 7 days and 3 months later) by using of a 5-point scale. In addition to routine neurophysiological monitoring, comparative mono- and bipolar mapping of the pyramidal tract within the bed of excised tumor was carried out at the end of surgery. The points of motor responses were marked. Comparative analysis of mono- and bipolar stimulation at identical points included threshold amperage, frequency of positive motor responses and the number of muscles involved in response (leg, forearm, hand, facial muscles). Brain MRI was performed in early postoperative period for assessment of resection quality. RESULTS: There were 64 points of motor responses in 14 patients. The number of these points ranged from 2 to 8 per a patient (mean 5 points). Motor responses were recorded in 57 points during monopolar and bipolar stimulation, in other 7 points - only during monopolar stimulation. Amperage of monopolar stimulation was 3-15 mA, bipolar stimulation - 2.5-25 mA. Threshold amperage (7.37 mA for monopolar stimulation and 8.88 mA for bipolar stimulation; p=0.12), frequency of positive motor responses and the number of muscles involved in response (p=0.1 and p=0.73) were similar. Seven (50%) patients had neurological deterioration in early postoperative period (4 patients with glial tumors and 3 patients with meningiomas). At the same time, only 2 patients (14.3%) had persistent neurological deficit (both patients with infiltrative meningioma). According to postoperative MRI in T1+C mode, resection volume was 100% in 1 patient with contrast-enhanced glioma and 94% in another one. According to FLAIR MRI data, resection volume exceeded 70% in 2 patients with non-enhancing glioma and less than 70% in 2 patients. Meningioma resection volume was estimated according to postoperative T1+C MRI data and made up over 90% in 4 patients. CONCLUSION: Monopolar stimulation is a reliable method of pyramidal tract identification in supratentorial brain tumor surgery.

Pathological factors contributing to crossed cerebellar diaschisis in cerebral gliomas: a study combining perfusion, diffusion, and structural MR imaging.

PURPOSE: To investigate imaging features of crossed cerebellar diaschisis (CCD) in cerebral gliomas, and its underlying pathophysiological mechanisms. METHODS: Thirty-three pre-surgical patients with cerebral gliomas and 33 healthy controls underwent arterial spin-labeling, diffusion tensor imaging, and high-resolution T1-weighted imaging using MRI, in order to estimate cerebral blood flow (CBF), white matter integrity, and lesion volume, respectively. Asymmetry indices of CBF in the cerebellum were used for evaluating the level of CCD in the patients. These indices were correlated with clinical variables (lesion size and position, tumor histological grade, and CBF asymmetry) and diffusion tensor imaging parameters (fractional anisotropy and number of fibers in the cortico-ponto-cerebellar pathway and across the cerebral hemispheres), respectively. RESULTS: The patients showed decreased CBF in the cerebellar hemisphere contralateral to the supratentorial tumor, and increased CBF asymmetry in the cerebellum (both P < 0.05). CCD levels in high-grade gliomas were higher than those of low-grade gliomas (P < 0.05). CCD levels were negatively correlated with the size of the supratentorial lesions, and positively correlated with FA asymmetry in the cerebral fibers (both P < 0.05). CONCLUSIONS: CCD in cerebral gliomas was specifically associated with tumor histological grade, lesion size, and white matter impairments in the hemisphere ipsilateral to the tumor. The findings implicated that observing CCD might have potential for assisting grading diagnosis of cerebral gliomas.

Image-guided resection of glioblastoma in eloquent brain areas facilitated by laser surface thermal therapy: clinical outcomes and long-term results.

The increased interest in the application of lasers in neuro-oncology prompted us to present our experience of using the laser technologies in the treatment of cerebral gliomas. The aim of the study was to evaluate the clinical efficacy of image-guided laser surface thermal therapy (LSTT) and its influence on survival of patients with glioblastoma (GBM).Data of 91 patients (49 males, 42 females, mean age 51.4 years, range 23-70 years) with supratentorial GBMs located in close vicinity to or within the eloquent brain areas were retrospectively analyzed.All patients were divided into two groups: LSTT group (n = 28) and control group (n = 63). There were no significant differences by gender, age, Karnofsky Performance Scale (KPS) score, and tumor location between groups. Total removal in the LSTT group was performed in 67.9%, in the control group-31.7% (p < 0.01); on the contrary, subtotal removal prevailed in the control group-52.4%; in the LSTT group, it was 32.1%. In postoperative period, there was no significant difference in KPS score between the groups (p = 0.89). A higher degree of resection provided an increase in survival rates (p < 0.01). The median overall survival was 15.5 ± 10.5 months, in the LSTT group 18.4 ± 11.7 and in the control group 14.3 ± 9.1 (p = 0.03). The application of image-guided LSTT in patients with GBMs of eloquent brain areas allowed the high rate of complete resection and improved overall survival without the negative effect on the functional status after surgery.

Historadiological correlations in high-grade glioma with the histone 3.3 G34R mutation.

BACKGROUND AND PURPOSE: Molecular alterations were recently added to the World Health Organization (WHO) 2016 classification of central nervous system (CNS) tumors. We correlated the histological and radiological features of G34R mutant high-grade gliomas, a recently described hemispheric and supratentorial glioma of children and young adults. MATERIALS AND METHODS: We performed a retrospective multicenter study on the histopathological and MRI results of 12 patients. RESULTS: All tumors were supratentorial. Several radiological aspects were observed. Height over 12 were bulky and well delineated tumors, without visible peritumoral infiltration on MRI and pathologically characterized by highly cellular tissue associated with a moderate peritumoral infiltrative component. Two tumors were ill-defined and hyperintense on T2 sequences and pathologically characterized by diffuse tumoral infiltration. Two tumors were bulky and well delineated with an infiltrative component, both radiologically and histopathologically. CONCLUSIONS: These different patterns may correspond to different pathological mechanisms and a potential link with prognosis should be assessed in further studies.

[Astroblastoma: A rare glial tumor]. / L'astroblastome : une tumeur gliale rare.

Astroblastoma is a rare neuroepithelial tumor most commonly seen in children and young adults. Due to its rarity, this tumor can be easily misdiagnosed as its classification, histogenesis and therapeutic management are still being discussed. We report the case of a 21 year old man, who presented at the Emergency Room for loss of consciousness. He reported a history of headaches, vomiting and decreased visual acuity. The CT and MRI showed a left temporoparietal solid-cystic mass with heterogeneous enhancement and perilesional edema. The patient underwent a total mass resection. On histopathological examination, tumor cells were organized in perivascular pseudorosettes which are typically encountered in astroblastoma, without neither necrosis nor endothelial hyperplasia. They had broad processes and rounded nuclei without any mitotic activity. Immunochemistry stains confirmed the diagnosis by showing a positive reactivity for GFAP, EMA, vimentin and S100. Astroblastoma is a rare glial tumor of uncertain origin. Clinical presentation and imaging are nonspecific. Therefore, its diagnosis is based on histopathologic findings: typical perivascular pseudorosettes. However, similar histological pattern may be seen in other glial neoplasms. In the 2016 WHO Classification, astroblastoma is among the "other glial neoplasms" without a grading system. So far, there are no reliable prognosis factors for this tumor; however, two entities have been described: well differenciated astroblastoma (considered as low grade) and anaplastic/malignant astroblastomas (considered as high grade). Gross total resection is the treatment of choice for astroblastomas. Adjuvant therapy is still controversial. This case illustrates a cerebral tumor which is rarely encountered in practice and that can cause diagnostic problems and subsequently, inadequate treatment.

[Magnetic Resonance Imaging Features of the Supratentorial Extra-axial Hemangioblastoma:A Case Report].

We reported a case of supratentorial extra-axial hemangioblastoma diagnosed by magnetic resonance imaging (MRI). As a simple solid mass,this tumor has its unique MRI features due to its tissue structures.