AI-based Virtual Synthesis of Methionine PET from Contrast-enhanced MRI: Development and External Validation Study.

Background Carbon 11 (11C)-methionine is a useful PET radiotracer for the management of patients with glioma, but radiation exposure and lack of molecular imaging facilities limit its use. Purpose To generate synthetic methionine PET images from contrast-enhanced (CE) MRI through an artificial intelligence (AI)-based image-to-image translation model and to compare its performance for grading and prognosis of gliomas with that of real PET. Materials and Methods An AI-based model to generate synthetic methionine PET images from CE MRI was developed and validated from patients who underwent both methionine PET and CE MRI at a university hospital from January 2007 to December 2018 (institutional data set). Pearson correlation coefficients for the maximum and mean tumor to background ratio (TBRmax and TBRmean, respectively) of methionine uptake and the lesion volume between synthetic and real PET were calculated. Two additional open-source glioma databases of preoperative CE MRI without methionine PET were used as the external test set. Using the TBRs, the area under the receiver operating characteristic curve (AUC) for classifying high-grade and low-grade gliomas and overall survival were evaluated. Results The institutional data set included 362 patients (mean age, 49 years ± 19 [SD]; 195 female, 167 male; training, n = 294; validation, n = 34; test, n = 34). In the internal test set, Pearson correlation coefficients were 0.68 (95% CI: 0.47, 0.81), 0.76 (95% CI: 0.59, 0.86), and 0.92 (95% CI: 0.85, 0.95) for TBRmax, TBRmean, and lesion volume, respectively. The external test set included 344 patients with gliomas (mean age, 53 years ± 15; 192 male, 152 female; high grade, n = 269). The AUC for TBRmax was 0.81 (95% CI: 0.75, 0.86) and the overall survival analysis showed a significant difference between the high (2-year survival rate, 27%) and low (2-year survival rate, 71%; P < .001) TBRmax groups. Conclusion The AI-based model-generated synthetic methionine PET images strongly correlated with real PET images and showed good performance for glioma grading and prognostication. Published under a CC BY 4.0 license. Supplemental material is available for this article.

Schwannoma-like tumor in the anterior cranial fossa immunonegative for Leu7 but immunopositive for Schwann/2E.

Schwannoma arising from the olfactory system, often called olfactory groove schwannoma (OGS), is rare, as the olfactory bulb and tract, belonging to the central nervous system, should lack Schwann cells. Another rare entity called olfactory ensheathing cell tumor (OECT) has been reported, which mimics clinical and radiological characteristics of OGS. Here, we report two rare cases of schwannoma-like tumor in the anterior cranial fossa that showed negative staining for Leu7, but positive staining for Schwann/2E, and discuss their origin. Two cases of mass lesions in the anterior cranial fossa in a 26-year-old man and a 24-year-old woman were successfully removed. Morphological examination of these tumors was compatible with a diagnosis of schwannoma. Immunohistochemically, both cases were negative for Leu7, yielding a diagnosis of OECT, but were positive for the schwannoma-specific marker, Schwann/2E. Immunohistochemical staining results in our two cases question the current assumption that OGS and OECT can be distinguished only by Leu7 staining pattern. In conclusion, the origins of OGS and OECT remain to be determined, and further studies in larger numbers of cases are needed to characterize these rare tumors in the anterior cranial fossa.

Case report and review of the literature of primary central nervous system lymphoma of the fourth ventricle.

Background: Primary central nervous system lymphoma of the fourth ventricle is very rare. We present a case of primary central nervous system lymphoma originating from the fourth ventricle and review cases reported in the literature. Case Description: A 54-year-old man with no previous medical history presented with headache and nausea. Magnetic resonance imaging showed a homogeneously enhancing tumor in the fourth ventricle and obstructive hydrocephalus. We performed biopsy of the tumor, which was diagnosed pathologically as diffuse large B-cell lymphoma. Although the tumor disappeared after 5 cycles of R-MPV regimen, the patient required repeated ventricular drainage and finally received a ventriculoperitoneal shunt. Complete response was achieved after 2 cycles of high-dose cytarabine chemotherapy with an autologous peripheral blood stem cell transplant. There was no sign of recurrence at 20 months after biopsy. Conclusion: Morbidity arising due to radical resection/radiotherapy of resistant primary central nervous system lymphoma originating from the fourth ventricle could be prevented by ventriculoperitoneal shunting with chemotherapy and autologous blood stem cell transplantation.

Visualization of Resected Area in Endonasal Endoscopic Approach versus Transcranial Approach for Skull Base Meningiomas by Voxel-Based-Lesion Mapping.

BACKGROUND: We aimed to evaluate the resected area of endonasal endoscopic approach (EEA) and transcranial approach (TCA) for skull base meningiomas (SBMs) using voxel-based-lesion mapping and visualized the appropriate tumor location in each approach. METHODS: We retrospectively examined 182 patients with SBMs who underwent tumor resection in our hospital between 2014 and 2019. Pre- and post-operative SBMs were manually delineated on MRI to create the voxels-of-interest (VOIpre and VOIpost) and were registered onto the normalized brain (normalized VOIpre and normalized VOIpost). The resected map was created by subtracting normalized VOIpost from the normalized VOIpre divided by the number of cases. The resected maps of TCA and EEA were compared by subtracting them. RESULTS: Twenty patients underwent EEA and 135 patients underwent TCA. The tumor resected map demonstrated that the resected area of EEA frequently accumulated on the central skull base, while that of TCA accumulated near the central skull base. The border of both approaches matched the circle that connects neural foramens at the skull base. CONCLUSIONS: The resected area of SBMs by EEA and TCA was well visualized by voxel-based-lesion mapping. The circle connecting the neural foramens was the border of EEA and TCA.

Endoscopic Contralateral Interhemispheric Transfalcine Keyhole Approach for Large Falcine Meningiomas.

OBJECTIVE: Falcine meningioma is usually approached ipsilaterally, and the technique for tumor removal has traditionally been performed under microscopy. We report a surgical procedure for large falcine meningioma by an endoscopic contralateral interhemispheric transfalcine keyhole approach. METHODS: The study period was from September 2019 to March 2021. Study participants were patients with World Health Organization grade I meningioma showing falx attachment, excluding neurofibromatosis, who underwent initial surgery at our institution. The surgical procedure begins with a small contralateral craniotomy of about 3 cm, followed by insertion of an endoscope. The tumor attachment to the falx is excised, exposing the tumor. Internal decompression is performed, and the lesion is dissected from the surrounding brain before removal through the falx. RESULTS: An endoscopic contralateral interhemispheric transfalcine keyhole approach was used to resect 4 cases of large falcine meningioma. The mean operation time was 265 minutes (range: 216-294 minutes), achieving Simpson grade I removal in all cases. No evidence of cerebral infarction, cerebral edema, or new neurological complaints related to impaired venous return was seen using this surgical method. CONCLUSIONS: In the case of falcine meningioma, the endoscopic keyhole contralateral technique allows detachment of the tumor from the falx and safe manipulation in a minor field of view. In addition, because the craniotomy is smaller and the operation time is shorter, this procedure offers a less-invasive approach for the patient. This technique is thus, in our opinion, quite advantageous.

Maximum 11C-methionine PET uptake as a prognostic imaging biomarker for newly diagnosed and untreated astrocytic glioma.

This study aimed whether the uptake of amino tracer positron emission tomography (PET) can be used as an additional imaging biomarker to estimate the prognosis of glioma. Participants comprised 56 adult patients with newly diagnosed and untreated World Health Organization (WHO) grade II-IV astrocytic glioma who underwent surgical excision and were evaluated by 11C-methionine PET prior to the surgical excision at Osaka City University Hospital from July 2011 to March 2018. Clinical and imaging studies were retrospectively reviewed based on medical records at our institution. Preoperative Karnofsky Performance Status (KPS) only influenced progression-free survival (hazard ratio [HR] 0.20; 95% confidence interval [CI] 0.10-0.41, p < 0.0001), whereas histology (anaplastic astrocytoma: HR 5.30, 95% CI 1.23-22.8, p = 0.025; glioblastoma: HR 11.52, 95% CI 2.27-58.47, p = 0.0032), preoperative KPS ≥ 80 (HR 0.23, 95% CI 0.09-0.62, p = 0.004), maximum lesion-to-contralateral normal brain tissue (LN max) ≥ 4.03 (HR 0.24, 95% CI 0.08-0.71, p = 0.01), and isocitrate dehydrogenase (IDH) status (HR 14.06, 95% CI 1.81-109.2, p = 0.011) were factors influencing overall survival (OS) in multivariate Cox regression. OS was shorter in patients with LN max ≥ 4.03 (29.3 months) than in patients with LN max < 4.03 (not reached; p = 0.03). OS differed significantly between patients with IDH mutant/LN max < 4.03 and patients with IDH mutant/LN max ≥ 4.03. LN max using 11C-methionine PET may be used in prognostic markers for newly identified and untreated WHO grade II-IV astrocytic glioma.

Disconnection surgery to cure or palliate medically intractable epileptic spasms: a retrospective study.

OBJECTIVE: Surgery is a treatment option for medically intractable epileptic spasms (ESs). However, outcomes of ES after surgery are not well understood, especially when surgeries aimed at seizure palliation are included. The purpose of the present study was to 1) investigate the proportion of favorable postoperative ES outcomes, 2) explore the preoperative factors related to favorable postoperative ES outcomes, and 3) examine the timing of ES recurrence after disconnection surgeries, including both curative and palliative indications. METHODS: This retrospective study included patients who underwent disconnection surgery for medically intractable ES at the authors' institution between May 2015 and April 2021. Patients with suggested focal-onset ES based on preoperative evaluations initially underwent lobar disconnection. Patients with suggested generalized or unknown-onset ES underwent corpus callosotomy (CC). If evaluations after initial CC showed focalized or lateralized change, they were considered secondarily revealed focal-onset ES, and lobar disconnection was performed. ES outcomes were evaluated using the International League Against Epilepsy classification. ES outcomes were divided into classes 1-4 as favorable outcomes and classes 5 and 6 as unfavorable outcomes. The relationship between the favorable postoperative ES outcomes and the following preoperative factors was analyzed: sex, age at onset (< or > 1 year), duration between seizure onset and initial surgery (< or > 2 years), type of seizure at onset (ES or others), presence of other types of seizures, substrate, hypsarrhythmia, and MRI abnormalities. The period between the last surgery and ES recurrence was also analyzed. RESULTS: A total of 41 patients were included, of whom 75.6% achieved favorable ES outcomes. A longer seizure duration between seizure onset and initial surgery, presence of hypsarrhythmia, and positive MRI findings led to poorer postoperative ES outcomes (p = 0.0028, p = 0.0041, and p = 0.0241, respectively). A total of 60.9% of patients had ES recurrence during the follow-up period, and their ES recurred within 13 months after the last surgery. CONCLUSIONS: Disconnection surgery is an effective treatment option for medically intractable ES, even when the preoperative evaluation suggests a generalized or unknown onset.

Combination of p53 and Ki67 as a Promising Predictor of Postoperative Recurrence of Meningioma.

BACKGROUND: Meningioma is a common intracranial tumor originating from arachnoid cap cells. Meningiomas are generally benign tumors curable by one-time resection. However, some meningiomas regrow and invade into the dura mater, and thus frequently require additional treatment. A useful marker to predict the regrowth of meningioma is desired. This study aimed to clarify the significance of p53 and Ki67 for postoperative recurrence of meningioma. MATERIALS AND METHODS: The expression of p53 and Ki67 in 215 intracranial or intraspinal meningiomas was investigated by immunohistochemistry. RESULTS: Of the 215 meningiomas, 35 cases (16.3%) were p53-positive and 49 cases (22.8%) were Ki67-positive. Multivariate analysis revealed Ki67 and p53 status as being significantly correlated with recurrence. Positivity for either Ki67- or p53 was significantly associated with poor recurrence-free survival. CONCLUSION: Combined p53 and Ki67 status might represent a useful independent predictive marker for recurrence of meningioma.

Specific Oscillatory Power Changes and Their Efficacy for Determining Laterality in Mesial Temporal Lobe Epilepsy: A Magnetoencephalographic Study.

Appropriate determination of the epileptic focus and its laterality are important for the diagnosis of mesial temporal lobe epilepsy (MTLE). The aims of this study are to establish a specific oscillatory distribution and laterality of the oscillatory power in unilateral MTLE with frequency analysis of magnetoencephalography (MEG), and to confirm their potential to carry significant information for determining lateralization of the epileptic focus. Thirty-five patients with MTLE [left (LtMTLE), 16; right (RtMTLE), 19] and 102 healthy control volunteers (CTR) were enrolled. Cortical oscillatory powers were compared among the groups by contrasting the source images using a one-way ANOVA model for each frequency band. Further, to compare the lateralization of regional oscillatory powers between LtMTLEs and RtMTLEs, the laterality index (LI) was calculated for four brain regions (frontal, temporal, parietal, and occipital) in each frequency band, which were compared between patient groups (LtMTLE, RtMTLE, and CTR), and used for machine learning prediction of the groups with support vector machine (SVM) with linear kernel function. Significant oscillatory power differences between MTLE and CTR were found in certain areas. In the theta to high-frequency oscillation bands, there were marked increases in the parietal lobe, especially on the left side, in LtMTLE. In the theta, alpha, and high-gamma bands, there were marked increases in the parietal lobe, especially on the right side in RtMTLE. Compared with CTR, LIs were significantly higher in 24/28 regions in LtMTLE, but lower in 4/28 regions and higher in 10/28 regions in RtMTLE. LI at the temporal lobe in the theta band was significantly higher in LtMTLE and significantly lower in RtMTLE. Comparing LtMTLE and RtMTLE, there were significant LI differences in most regions and frequencies (21/28 regions). In all frequency bands, there were significant differences between LtMTLE and RtMTLE in the temporal and parietal lobes. The leave-one-out cross-validation of the linear-SVM showed the classification accuracy to be over 91%, where the model had high specificity over 96% and mild sensitivity ~68-75%. Using MEG frequency analysis, the characteristics of the oscillatory power distribution in the MTLE were demonstrated. Compared with CTR, LIs shifted to the side of the epileptic focus in the temporal lobe in the theta band. The machine learning approach also confirmed that LIs have significant predictive ability in the lateralization of the epileptic focus. These results provide useful additional information for determining the laterality of the focus.

Diagnostic Performance of [11C]Methionine Positron Emission Tomography in Newly Diagnosed and Untreated Glioma Based on the Revised World Health Organization 2016 Classification.

BACKGROUND: The relationship between uptake of amino acid tracer with positron emission tomography (PET) and glioma subtypes/gene status is still unclear. OBJECTIVE: To assess the relationship between uptake of [11C]methionine using PET and pathology, IDH (isocitrate dehydrogenase) mutation, 1p/19q codeletion, and TERT (telomerase reverse transcriptase) promoter status in gliomas. METHODS: The participants were 68 patients with newly diagnosed and untreated glioma who underwent surgical excision and preoperative [11C]methionine PET examination at Osaka City University Hospital between July 2011 and March 2018. Clinical and imaging studies were reviewed retrospectively based on the medical records at our institution. RESULTS: The mean lesion/contralateral normal brain tissue (L/N) ratio of diffuse astrocytomas was significantly lower than that of anaplastic astrocytomas (P = 0.00155), glioblastoma (P < 0.001), and oligodendrogliomas (P = 0.0157). The mean L/N ratio of IDH mutant gliomas was significantly lower than that of IDH wild-type gliomas (median 1.75 vs. 2.61; P = 0.00162). A mean L/N ratio of 2.05 provided the best sensitivity and specificity for distinguishing between IDH mutant and IDH wild-type gliomas (69.2% and 76.2%, respectively). The mean L/N ratio of TERT promoter mutant gliomas was significantly higher than that of TERT promoter wild-type gliomas (P = 0.0147). Multiple regression analysis showed that pathologic diagnosis was the only influential factor on L/N ratio. CONCLUSIONS: Distinguishing glioma subtypes based on the revised 2016 World Health Organization classification of the central nervous system tumors on the basis of [11C]methionine PET alone seems to be difficult. However, [11C]methionine PET might be useful for predicting the IDH mutation status in newly diagnosed and untreated gliomas noninvasively before tumor resection.

Phase-amplitude coupling of interictal fast activities modulated by slow waves on scalp EEG and its correlation with seizure outcomes of disconnection surgery in children with intractable nonlesional epileptic spasms.

OBJECTIVE: Epileptic spasms (ESs) are classified as focal, generalized, or unknown onset ESs. The classification of ESs and surgery in patients without lesions apparent on MRI is challenging. Total corpus callosotomy (TCC) is a surgical option for diagnosis of the lateralization and possible treatment for ESs. This study investigated phase-amplitude coupling (PAC) of fast activity modulated by slow waves on scalp electroencephalography (EEG) to evaluate the strength of the modulation index (MI) before and after disconnection surgery in children with intractable nonlesional ESs. The authors hypothesize that a decreased MI due to surgery correlates with good seizure outcomes. METHODS: The authors studied 10 children with ESs without lesions on MRI who underwent disconnection surgeries. Scalp EEG was obtained before and after surgery. The authors collected 20 epochs of 3 minutes each during non-rapid eye movement sleep. The MI of the gamma (30-70 Hz) amplitude and delta (0.5-4 Hz) phase was obtained in each electrode. MIs for each electrode were averaged in 4 brain areas (left/right, anterior/posterior quadrants) and evaluated to determine the correlation with seizure outcomes. RESULTS: The median age at first surgery was 2.3 years (range 10 months-9.1 years). Two patients with focal onset ESs underwent anterior quadrant disconnection (AQD). TCC alone was performed in 5 patients with generalized or unknown onset ESs. Two patients achieved seizure freedom. Three patients had residual generalized onset ESs. Disconnection surgeries in addition to TCC consisted of TCC + posterior quadrant disconnection (PQD) (1 patient); TCC + AQD + PQD (1 patient); and TCC + AQD + hemispherotomy (1 patient). Seven patients became seizure free with a mean follow-up period of 28 months (range 5-54 months). After TCC, MIs in 4 quadrants were significantly lower in the 2 seizure-free patients than in the 6 patients with residual ESs (p < 0.001). After all 15 disconnection surgeries in 10 patients, MIs in the 13 target quadrants for each disconnection surgery that resulted in freedom from seizures were significantly lower than in the 26 target quadrants in patients with residual ESs (p < 0.001). CONCLUSIONS: In children with nonlesional ESs, PAC for scalp EEG before and after disconnection surgery may be a surrogate marker for control of ESs. The MI may indicate epileptogenic neuronal modulation of the interhemispheric corpus callosum and intrahemispheric subcortical network for ESs. TCC may be a therapeutic option to disconnect the interhemispheric modulation of epileptic networks.

Comparison of the keyhole trans-middle temporal gyrus approach and transsylvian approach for selective amygdalohippocampectomy: A single-center experience.

Several approach routes exist for selective amygdalohippocampectomy (SAH); however, previous reports regarding a comparison of these routes are limited. Here, we compared trans-middle temporal gyrus (T2) SAH and transsylvian (TS) SAH in terms of seizure outcome, visual-field defect, memory function, and operation time in our institution. This retrospective study examined the data of 16 patients with medically intractable mesial temporal lobe epilepsy. Six patients underwent trans-T2 SAH and 10 patients underwent TS SAH between July 2014 and February 2019 in Osaka City University Hospital. In trans-T2 SAH, we performed a keyhole temporal craniotomy and a small corticotomy on T2. In TS SAH, we performed a 1.5 cm corticotomy along the inferior periinsular sulcus after opening the sylvian fissure. Amygdalohippocampectomy after reaching the inferior horn of the lateral ventricle was performed in the same manner in both procedures. The seizure outcome, visual-field defect, memory function, and operation time were retrospectively compared between the procedures. Seizure-free outcomes were achieved for six patients in the trans-T2 SAH and eight patients in the TS SAH group. There were no significant differences in the seizure outcome, visual-field defect, and memory function. The operation time was significantly shorter for trans-T2 SAH than TS SAH. The postoperative scar was less conspicuous for trans-T2 SAH. Trans-T2 SAH and TS SAH were comparable in terms of the seizure outcome, visual-field defect, and memory function. The operation time and length of the skin incision were shorter for trans-T2 SAH, suggesting that it may be preferable for general epilepsy surgeons.

Changes in cognitive function after resection of lesions in the anterior part of the lateral ventricle via an interhemispheric transcallosal approach.

Anterior callosotomy to about 20 mm has been considered relatively safe empirically. The present study aimed to compare cognitive function before and after resection of tumors in the anterior part of the lateral ventricle. We analyzed 6 patients with intraventricular tumors located in the anterior horn or body of the lateral ventricle who underwent surgical excision via interhemispheric transcallosal approach at Osaka City University Hospital between March 2015 and August 2018. And clinical and imaging studies, neuropsychological function using MMSE, WAIS-III and WMS-R and surgical complications were retrospectively reviewed based on the medical records at our institution. As a result, 4 patients achieved gross total resection of the tumor and 2 patients achieved subtotal resection. 4 patients showed hydrocephalus, which disappeared in each case within 6 months after tumor resection. Mean length of callosotomy was 16.9 mm (range, 15.5-26.1 mm). One patient showed postoperative transient deficits including aphasia, microphonia, ballism in all extremities and hemiplegia, and another patient experienced subjective difficulty when talking. These symptoms disappeared within 3 months after tumor resection. Scores from the MMSE and WAIS-III showed no significant postoperative deterioration. Performance intelligence quotient (P = 0.04), full intelligence quotient (P = 0.04) and perceptual organization (P = 0.03) of WAIS-III were significantly improved after surgery compared with preoperatively. In conclusion, anterior corpus callosotomy of about 20 mm for intraventricular tumor in the anterior horn or body of the lateral ventricle might have little effect on cognitive function in the chronic phase, although the influence of hydrocephalus cannot be ignored.

Anatomic Understanding of Subtotal Hemispherotomy Using Cadaveric Brain, 3-Dimensional Simulation Models, and Intraoperative Photographs.

BACKGROUND: When the epileptogenic foci skip the motor area, the epilepsy can be cured by surgery while preserving the motor function. This surgery has been reported as subtotal hemispherectomy. The disconnective variant of this surgery, subtotal hemispherotomy, is described. OBJECTIVE: To demonstrate each step clearly, a cadaveric brain, 3-dimensional reconstruction and simulation model, and intraoperative photographs were used. METHODS: A formalin-fixed cadaveric brain was dissected to show each step of this surgery. For the 3-dimensional model, several brain structures were reconstructed from preoperative images, and the surgery was simulated. Intraoperative photographs and postoperative magnetic resonance images were taken from the representative cases. RESULTS: Temporo-parieto-occipital disconnection is performed to disconnect these lobes and the insula, limbic system, and splenium of the corpus callosum. The postcentral sulcus is the anterior border of the disconnection. Next, prefrontal disconnection is performed to disconnect the frontal lobe and the insula, frontal lobe and basal ganglia, and the anterior part of the corpus callosum. The precentral sulcus is the posterior border of the disconnection. Finally, corpus callosotomy of the central part is performed. After these steps, subtotal hemispherotomy, with preservation of the pre- and postcentral gyrus, is achieved. The 3-dimensional model clearly shows the anatomic relationships between deep brain structures. In the representative cases, postoperative motor deterioration was transient or none, and seizure-free status was achieved after surgery. CONCLUSION: Subtotal hemispherotomy is generally difficult because of the complicated anatomy and narrow and deep surgical corridors. Combined use of these methods facilitates a clearer understanding of this surgery.

Intracavernous Hemangiopericytoma: Case Report and Review of the Literature.

Intracavernous hemangiopericytoma/solitary fibrous tumor is an extremely rare tumor, with only seven cases reported. We present a case of intracavernous hemangiopericytoma/solitary fibrous tumor and review all cases reported in the literature. A 67-year-old man experienced numbness over the left half of the face. Magnetic resonance imaging revealed a left intracavernous tumor extending into Meckel's cave and the posterior fossa. We performed gamma knife surgery (GKS) which a prescribed dose to the tumor of 12 Gy, but tumor recurred 43 months after GKS. We performed partial tumor resection via a subtemporal interdural approach. The pathological diagnosis was hemangiopericytoma. Postoperatively, we performed second GKS with a prescribed dose of 15 Gy. Diplopia and ptosis improved markedly and the tumor initially reduced in size, but tumor regrowth was seen again 29 months after second GKS. Third GKS was performed with a prescribed dose of 15 Gy. Recurrence was not seen at 18 months after third GKS, but was identified about 2 years after third GKS. We performed fourth GKS with a prescribed dose to the residual tumor of 16 Gy. We report a rare case of intracavernous hemangiopericytoma originating in the cavernous sinus, but distinguishing between hemangiopericytoma and schwannoma is difficult for round, intracavernous tumors showing homogeneous enhancement without flow voids. GKS might be one of the options for residual and recurrent intracavernous hemangiopericytomas.

Surgically treated intracranial supratentorial calcifying pseudoneoplasms of the neuraxis (CAPNON) with drug-resistant left temporal lobe epilepsy: A case report and review of the literature.

Calcifying pseudoneoplasms of the neuraxis (CAPNON) are rare pathological lesions that can present anywhere in the central nervous system. Symptoms vary depending on the location, though they often include seizures, especially in intracranial and supratentorial lesions. A case of intracranial supratentorial CAPNON presenting with drug-resistant left temporal lobe epilepsy is reported. The patient had a history of drug-resistant focal seizures for over 36 years. The lesion was located in the left mesial temporal lobe, but hippocampal sclerosis and hippocampal invasion were not apparent. The lesion was removed without hippocampectomy, and the patient has been seizure-free for one year.

Oligodendrocytes Up-regulate the Invasive Activity of Glioblastoma Cells via the Angiopoietin-2 Signaling Pathway.

BACKGROUND/AIM: Glioblastoma (GBM) is one of the most lethal solid cancers due to its highly invasive nature. The malignant potential of GBM cells might be partially regulated by surrounding normal cells, such as oligodendrocytes or fibroblasts. The aim of this study was to examine the interaction between stromal cells and GBM cells. MATERIALS AND METHODS: Two GBM cell lines were used. The effect of stromal cells, oligodendrocytes or fibroblasts, on the invasive ability of GBM cells was examined by wound-healing assay and invasion assay. RESULTS: Oligodendrocytes, in contrast to fibroblasts, significantly increased the migration and invasive ability of GBM cells. Angiopoietin-2 levels were high in the conditioned medium obtained from oligodendrocytes. Angiopoietin-2 significantly increased the motility of GBM, and the motility-stimulating activity of the oligodendrocytes-derived conditioned medium was significantly decreased by anti-angiopoietin-2-neutralizing antibody. CONCLUSION: Glioma stromal cells, oligodendrocytes, might up-regulate the invasiveness of GBM cells via angiopoietin-2 signaling.

Case Report and Review of the Literature of Schwannomas That Originate from Falx Cerebri.

BACKGROUND: Schwannomas not related to cranial nerves are rare. Here, we present a case of a schwannoma that originated from the falx cerebri and review reported cases in the literature. CASE DESCRIPTION: A 36-year-old male experienced generalized seizures following right hemiparesis predominantly in his lower extremity. Magnetic resonance imaging revealed a round tumor attached to the falx cerebri on the left side. Radiologically, the tumor appeared to be a falx meningioma. We performed gross total removal of the tumor. Pathology showed a schwannoma that originated from the falx cerebri. Right hemiparesis disappeared soon after surgery. CONCLUSION: Although distinguishing a schwannoma of the falx cerebri from a falx meningioma and metastasis is difficult preoperatively, inclusion of schwannoma of the falx cerebri in the differential diagnosis is important, especially when the patient is relatively young and/or the tumor lacks a dural tail sign.

Adult-Onset Mixed Germ Cell Tumor Composed Mainly of Yolk Sac Tumor Around the Pineal Gland: A Case Report and Review of the Literature.

BACKGROUND: Mixed germ cell tumors (MGCTs) usually occur in children. In the present report, we discuss an extremely rare case of adult-onset MGCT composed mainly of yolk sac tumor (YST) around the pineal gland. CASE DESCRIPTION: A 54-year-old Japanese man presented with disturbance of consciousness, Parinaud's syndrome, and gait disturbance. Magnetic resonance imaging revealed a pineal mass lesion, and subtotal resection of the tumor was achieved. The histologic diagnosis was MGCT, consisting mainly of YST. Although he underwent 5 courses of chemotherapy and craniospinal irradiation after surgery, tumor dissemination could not be controlled, and he died 10 months postoperatively. CONCLUSION: The present case highlights the need for clinicians to include YST in the differential diagnosis of acute progressive lesions around the pineal region, even in adult patients.