Giant Cell Astrocytoma Research Articles

Periventricular and Intraventricular Tumors in a Low-Income Country: Hard Learning Curve and Outcome of a Young Neurosurgeon from Burkina Faso

Background: Periventricular and Intraventricular processes are life-threatening conditions because of their propensity to obstruct Cerebrospinal fluid pathways and to compress highly functional and vital structures. There are deep-seated lesions requiring rigorous microsurgical technic for their resection. Methods: We retrospectively analyzed the profile and outcome of Periventricular and intraventricular processes operated by the same author since his return in his country in 2015, after graduated abroad in WFNS Rabat training center program 2023. Result: We defined 15 patients operated over 8 years. There were 4 processes in lateral ventricle (26.6%), 1 in third ventricle (6.6%), 2 thalamus processes (13.3%), 4 in fourth ventricle (26.6%) and finally 4 in cerebellar hemisphere and violating the fourth ventricle (26.6%). Various surgical approaches were used, such as contralateral interhemispheric transcallosal, classical interhemispheric transcallosal, Subfrontal transbasal translamina terminalis, Frontal Transcortical, Temporal trans T2, ventriculoperitoneal shunting, endoscopy, cerebellar transcotical approach and Telovelar approach. Surgical procedure duration was more than 10 hours in 12 cases (80%) and one third of the patients have been operated in 2018. When neurosurgical operative microscope was not available, ophthalmologic microscope or binocular with headlight were used to achieve the resection. Pathological examination revealed High-grade glioma, subependymal giant cell astrocytoma (SEGA), central neurocytoma, Subependymoma, Hemangioblastoma, pilocytique astrocytoma, Medulloblastoma, gemiocytic astrocytoma, atypical papilloma of choroid plexus, craniopharygioma and cyst of septum pellucidum. We reported good postoperative outcome in 10 cases (66.6%), moderate postoperative deficit in 1 case and 4 cases of postoperative death (26.6%) among which 3 cases of postoperative meningitis. Conclusion: Periventricular and intraventricular processes can be safely approach in low-income country with acceptable result. However young African Neurosurgeon should be trained to be comfortable with multiple surgical approaches and also with binocular as well as with microscope. WFNS training program is a strong basement for the take-off of young African neurosurgeon. Backing home should be the rule after training, to develop neurosurgery.

Bleeding solitary SEGA in non-tuberous sclerosis complex adolescent: a case illustration and review of literature.

Subependymal giant cell astrocytoma (SEGA) represents a benign brain tumor occurring in 5-20% of individuals diagnosed with tuberous sclerosis complex (TSC), serving as a major diagnostic criterion. The presence of SEGA in a patient often prompts consideration of TSC as a probable diagnosis, given its unique association with this disorder. Typically, only one additional major criterion or two minor criteria are necessary to fulfill the diagnostic criteria for TSC. However, in rare instances, SEGA may manifest in patients without clinical features of TSC, termed solitary SEGA. The occurrence of solitary SEGA in patients lacking both clinical manifestations of TSC and genetic confirmation is extremely rare. Furthermore, the presentation of SEGA with intratumoral bleeding is exceedingly uncommon. Here, we presented a case of bleeding solitary SEGA in non-TSC adolescent who underwent surgery and has remained free of disease for a minimum of 3years. Genetic analysis of peripheral blood and tumor tissue yielded negative results for TSC-related mutations. While SEGA occurrence in non-TSC patients is uncommon, it remains one of the possible diagnoses of intraventricular tumors. However, comprehensive genetic and physical evaluations are imperative to confirm the TSC status and guide further investigations and follow-up appropriately.

Targeting the EGFR pathway: An alternative strategy for the treatment of tuberous sclerosis complex?

Tuberous sclerosis complex (TSC) is caused by variants in TSC1/TSC2, leading to constitutive activation of the mammalian target of rapamycin (mTOR) complex 1. Therapy with everolimus has been approved for TSC, but variations in success are frequent. Recently, caudal late interneuron progenitor (CLIP) cells were identified as a common origin of the TSC brain pathologies such as subependymal giant cell astrocytomas (SEGA) and cortical tubers (CT). Further, targeting the epidermal growth factor receptor (EGFR) with afatinib, which is expressed in CLIP cells, reduces cell growth in cerebral TSC organoids. However, investigation of clinical patient-derived data is lacking. Observation of EGFR expression in SEGA, CT and focal cortical dysplasia (FCD) 2B human brain specimen and investigation of whether its inhibition could be a potential therapeutic intervention for these patients. Brain specimens of 23 SEGAs, 6 CTs, 20 FCD2Bs and 17 controls were analysed via immunohistochemistry to characterise EGFR expression, cell proliferation (via Mib1) and mTOR signalling. In a cell-based assay using primary patient-derived cells (CT n= 1, FCD2B n= 1 and SEGA n= 4), the effects of afatinib and everolimus on cell proliferation and cell viability were observed. EGFR overexpression was observed in histological sections of SEGA, CT and FCD2B patients. Both everolimus and afatinib decreased the proliferation and viability in primary SEGA, tuber and FCD2B cells. Our study demonstrates that EGFR suppression might be an effective alternative treatment option for SEGAs and tubers, as well as other mTOR-associated malformations of cortical development, including FCD2B.

Polymorphism of clinical manifestations of orphan diseases in children with ARID1A and ARID1B gene mutations

Polymorphism of clinical manifestations of orphan diseases in children with ARID1A and ARID1B gene mutations

Subependymal giant cell astrocytoma as presentation of tuberous sclerosis: a case report

BackgroundA case of tuberous sclerosis patient on long-term follow-up is reported here.Case presentationA 22-year-old female patient with epilepsy was diagnosed with tuberous sclerosis at the age of 12 years. At that time, a small subependymal giant cell astrocytoma has been detected along with the other signs of the disease. But the patient was not symptomatic of the intracranial lesion at that time. So, she was kept under follow-up with treatment for the epilepsy. Within 10 years, the lesion gradually enlarged and caused symptoms and the tumour had to be resected at the age of 22 years of age.ConclusionsSubependymal giant cell astrocytoma is very slow-growing low-grade tumour. If small and asymptomatic at the time of the initial diagnosis, resection is not advised. The patient should be kept under close follow-up.

Utility of combining OLIG2 and SOX10 IHC expression in CNS tumours: promising biomarkers for subtyping paediatric- and adult-type gliomas.

The SOX10 transcription factor is important for the maturation of oligodendrocytes involved in central nervous system (CNS) myelination. Currently, very little information exists about its expression and potential use in CNS tumour diagnoses. The aim of our study was to characterize the expression of SOX10 in a large cohort of CNS tumours and to evaluate its potential use as a biomarker. We performed immunohistochemistry (IHC) for SOX10 and OLIG2 in a series of 683 cases of adult- and paediatric-type CNS tumours from different subtypes. The nuclear immunostaining results for SOX10 and OLIG2 were scored as positive (≥10% positive tumour cells) or negative. OLIG2 and SOX10 were positive in diffuse midline gliomas (DMG), H3-mutant, and EZHIP-overexpressed. However, in all DMG, EGFR-mutant, SOX10 was constantly negative. In diffuse paediatric-type high-grade gliomas (HGG), all RTK1 cases were positive for both OLIG2 and SOX10. RTK2 cases were all negative for both OLIG2 and SOX10. MYCN cases variably expressed OLIG2 and were all immunonegative for SOX10. In glioblastoma, IDH-wildtype, OLIG2 was mostly positive, but SOX10 was variably expressed, depending on the epigenetic subtype. All circumscribed astrocytic gliomas were positive for both OLIG2 and SOX10 except pleomorphic xanthoastrocytomas, astroblastomas, MN1-altered, and subependymal giant cell astrocytomas. SOX10 was negative in ependymomas, meningiomas, pinealoblastomas, choroid plexus tumours, intracranial Ewing sarcomas, and embryonal tumours except neuroblastoma, FOXR2-activated. To conclude, SOX10 can be incorporated into the IHC panel routinely used by neuropathologists in the diagnostic algorithm of embryonal tumours and for the subtyping of paediatric and adult-type HGG.

Diagnostic utility of genetic alterations in distinguishing IDH-wildtype glioblastoma from lower-grade gliomas: Insight from next-generation sequencing analysis of 479 cases.

The accurate diagnosis and classification of gliomas are essential for appropriate treatment planning and prognosis prediction. This study aimed to investigate the molecular diagnostics of IDH-wildtype diffuse astrocytic gliomas and identify potential genetic variants that could differentiate glioblastoma (GBM) from lower-grade gliomas when DNA methylation analysis is not feasible. In total, 479 H3-and IDH-wildtype diffuse astrocytic gliomas were included in this study. All the cases were diagnosed according to the 2021 World Health Organization (WHO) classification of central nervous system (CNS) tumors. Panel sequencing data were collected, and clinicopathological information was retrieved from medical records. Genetic alterations and histological findings were analyzed to determine their diagnostic utility and prognostic implications. Out of 479 cases, 439 (91.6%) were diagnosed with GBM, including 28 cases that were molecularly diagnosed as GBM. However, 40 (8.4%) cases could not be classified according to the 2021 WHO classification and were diagnosed as lower-grade diffuse astrocytic glioma, IDH-wildtype, not elsewhere classified (LGNEC). In addition to the three genetic alterations included in the diagnostic criteria of GBM, PTEN and EGFR mutations were found to be enriched in GBM. Patients harboring mTOR pathway mutations demonstrated a more favorable prognosis and often exhibited morphology resembling subependymal giant cell astrocytoma, along with a high tumor mutational burden. Among patients with mTOR pathway mutations, those lacking molecular diagnostic features of GBM exhibited outstanding survival outcomes, even in the presence of grade 4 histology. Integration of molecular features enhanced the diagnostic accuracy of IDH-wildtype gliomas. Some molecular alterations enriched in GBM offer valuable insights for molecular diagnosis and glioma classification. Furthermore, high-grade diffuse astrocytic gliomas featuring mTOR pathway mutations in the absence of molecular diagnostic features of GBM could represent more favorable tumor types distinct from GBM.

Subependymal giant cell astrocytoma (SEGA), unrelated to tuberous sclerosis, NTRK positive

Subependymal giant cell astrocytoma (SEGA), unrelated to tuberous sclerosis, NTRK positive

Pediatric-Like Brain Tumors in Adults.

Pediatric brain tumors are different to those found in adults in pathological type, anatomical site, molecular signature, and probable tumor drivers. Although these tumors usually occur in childhood, they also rarely present in adult patients, either as a de novo diagnosis or as a delayed recurrence of a pediatric tumor in the setting of a patient that has transitioned into adult services.Due to the rarity of pediatric-like tumors in adults, the literature on these tumor types in adults is often limited to small case series, and treatment decisions are often based on the management plans taken from pediatric studies. However, the biology of these tumors is often different from the same tumors found in children. Likewise, adult patients are often unable to tolerate the side effects of the aggressive treatments used in children-for which there is little or no evidence of efficacy in adults. In this chapter, we review the literature and summarize the clinical, pathological, molecular profile, and response to treatment for the following pediatric tumor types-medulloblastoma, ependymoma, craniopharyngioma, pilocytic astrocytoma, subependymal giant cell astrocytoma, germ cell tumors, choroid plexus tumors, midline glioma, and pleomorphic xanthoastrocytoma-with emphasis on the differences to the adult population.

Congenital Tumors-Magnetic Resonance Imaging Findings with Focus on Rare Tumors.

Congenital tumors are rare and, owing to this rarity, there is limited information on many of them. A total of 839 fetal and postnatal MRI studies performed in the first 3 months of life were retrospectively reviewed. They were performed with the use of 1.5 T scanners. Seventy-six tumors were diagnosed based on fetal MRI between 20 and 37 gestational weeks, and 27 were found after birth, from 1 day of age to 3 months of life. Teratomas were the most common tumors in our dataset, mainly in the sacrococcygeal region (SCT), followed by cardiac rhabdomyomas and subependymal giant cell astrocytomas (SEGA) associated with TSC, and neuroblastomas. The group of less common tumors consisted of infantile fibrosarcomas, malignant rhabdoid tumors, mesoblastic nephromas and Wilms tumor, craniopharyngiomas, brain stem gliomas, desmoplastic infantile astrocytoma, choroid plexus carcinoma, glioblastoma, hemangiopericytoma, rhabdomyosarcoma, melanoma, mesenchymal hamartomas of the chest wall and the liver, and juvenile xanthogranuloma, with special consideration of blue rubber bleb nevus syndrome. MRI plays a significant role in further and better characterization of congenital tumors, leading to a correct diagnosis in many cases, which is crucial for pregnancy and neonatal management and psychological preparation of the parents. No diagnosis is impossible and can be absolutely excluded.

A rare case of subependymal giant cell astrocytoma presenting with spontaneous intratumoral hemorrhage

ABSTRACT Subependymal giant cell astrocytomas (SEGAs) are low-grade gliomas usually arising in the periventricular regions near the foramen of Monro seen exclusively with tuberous sclerosis complex. Incidence of hemorrhage in SEGA is less than 1% with only 10 cases reported in English literature. We present a similar case of SEGA with spontaneous intratumoral hemorrhage in a 35-year-old male with cutaneous manifestations of tuberous sclerosis complex and acute onset headache with convulsion.

Tuberous sclerosis complex, Clinic and pathology manifestations, Mini -review

Tuberous sclerosis complex (TSC) is an autosomal dominant neurocutaneous syndrome that affects almost all of the organs of the body, including the brain, heart, lungs, liver, and kidneys. Brain tumors in TSC patients include cortical tubers, subependymal nodules (SENs), and Subependymal giant cell astrocytomas (SEGAs). Seizures that occur in 92% of patients with TSC are an important cause of sudden deaths in them. Other organ involvement includes renal angiomyolipomas, lymphangioleiomyomatosis, cardiac rhabdomyomas, and cutaneous manifestations (hypomelanotic macules, angiofibroma, ungual fibromas, shagreen patch, and ‘confetti’ skin lesions). There is a criterion for tuberous sclerosis complex that consists of 11 major and 6 minor clinical features that diagnosis occurs based on it. The best way for a definitive diagnosis of TSC in a patient is by using genetic tests and histopathology. Immunohistochemistry is a helpful method in confirming the diagnosis of brain tumors in TSC. Immunostaining of SEGA shows positivity for GFAP and S-100 protein while neurofilament and synaptophysin are negative. Ki-67, which indicates nuclear proliferation, has a low proliferation index in immunostain. In an aggressive tumor, hydrocephalus, rising intracranial pressure and focal neurologic deficit, surgery is a necessity and can improve outcomes. Brain and kidney involvement in this disease is life-threatening. Brain involvement in these patients can lead to extensive neuropsychological complications, so the aim of this study is a concise review of the variable manifestations of this disease with a focus on the histopathological findings of brain involvement.

Imaging of supratentorial intraventricular masses in children: a pictorial review-part 2.

This article is the second in a two-part series aimed at exploring the spectrum of supratentorial intraventricular masses in children. In particular, this part delves into masses originating from cells of the ventricular lining, those within the septum pellucidum, and brain parenchyma cells extending into the ventricles. The aim of this series is to offer a comprehensive understanding of these supratentorial intraventricular masses, encompassing their primary clinical findings and histological definitions. We conducted a review and analysis of relevant epidemiological data, the current genetics/molecular classifications as per the fifth edition of the World Health Organization (WHO) Classification of Tumors of the Central Nervous System (WHO CNS5), and imaging findings. Each supratentorial intraventricular mass was individually evaluated, with a detailed discussion on its clinical and histological features. This article covers a range of supratentorial intraventricular masses observed in children. These include colloid cysts, subependymal giant cell astrocytomas, ependymomas, gangliogliomas, myxoid glioneuronal tumors, central neurocytomas, high-grade gliomas, pilocytic astrocytomas, cavernous malformations, and other embryonal tumors. Each mass type is characterized both clinically and histologically, offering an in-depth review of their individual imaging characteristics. The WHO CNS5 introduces notable changes, emphasizing the vital importance of molecular diagnostics in classifying pediatric central nervous system tumors. These foundational shifts have significant potential to impact management strategies and, as a result, the outcomes of intraventricular masses in children.

Subependymal giant cell astrocytoma, report of a rare case

Tuberous sclerosis complex (TSC) is a rare genetic disease that is inherited autosomal dominantly and may be associated with subependymal giant cell astrocytoma (SEGA) in 10-20% of cases. Different phenotypes are related to the form of lesions in different parts of the body, including skin, brain, kidneys, lungs, and heart. The age of the patient, the location of the tumor, and associated skin or neurological lesions may guide the pathologist for a definite diagnosis. Here we report a case of SEGA in an adolescent with TSC. Neurological clues including seizure and mental retardation, facial angiofibroma, renal mass, and histopathology examination of the brain tumor culminated in the diagnosis of TSC and SEGA.

Effectiveness and safety of everolimus treatment in patients with tuberous sclerosis complex in real-world clinical practice

BackgroundThe randomised double-blinded placebo-controlled EXIST-1–3 studies have showed everolimus effective with adverse effects reported as acceptable in treatment of symptoms in patients with tuberous sclerosis complex (TSC), although evidence of outcomes in clinical practice remains limited. This study aimed to investigate, in clinical practice, the effectiveness and safety of everolimus for epilepsy, renal angiomyolipoma (rAML), and subependymal giant cell astrocytoma (SEGA) in patients with TSC.ResultsThe study included 64 patients with TSC (median age: 19, range 0.9–54 years) receiving everolimus treatment (Norway: n = 35; Denmark: n = 29). Among 45 patients with epilepsy, 14 (31%) were responders experiencing ≥ 50% reduction in seizure frequency in the last 3 months of treatment compared with the last 3 months before treatment. Nineteen (42%) patients changed their anti-seizure medications (ASMs). Responders were more common among patients < 18 years (46%) than among patients ≥ 18 years (14%, p = 0.03). In 29 patients with rAML, everolimus reduced (≥ 30% decrease) and stabilized (< 20% increase, ≤ 30% decrease) longest diameter of rAML in 38% and 59%, respectively, after a mean treatment duration of 37 months. SEGA volume was reduced in three patients by 71%, 43%, and 48% after 39, 34, and 82 months. Adverse effects were reported in 61 of 64 patients (95%) after a median treatment duration of 31 months (range 0–106), with oral ulceration/stomatitis (63%) and upper respiratory tract infections (38%) being the most common. The most common laboratory abnormalities were increased cholesterol (41%), anaemia (30%), and leucopoenia (25%). Grade 3–4 adverse effects were reported in 36% of cases, and life-threatening conditions were reported in two patients. Nine patients discontinued everolimus treatment.ConclusionsSeizure reduction in this study sample was consistent with results from EXIST, but might be lower than expected, given that changes in concomitant ASMs are part of clinical practice. Seizure reduction was associated with younger age. As with EXIST, everolimus reduced or stabilised rAML size in most patients. SEGA volume was reduced in all three patients. Close follow-up is needed for this group, especially for children and patients who may not be able to report adverse effects.

10006-PEDT-1 PEDIATRIC LOWER GRADE GLIOMA SURGERY IN THE ERA OF GENOMIC MEDICINE

Abstract INTRODUCTION In the new WHO Brain Tumor Classification of 2021, pediatric-type gliomas are classified separately from adult-type tumors. Additionally, with the advancement of cancer genomics, treatment options have expanded. Here we consider surgery for pediatric low-grade gliomas. METHODS We retrospectively analyzed 41 cases of low-grade gliomas or glioneuronal tumors in patients under 18 years of age who underwent surgery at our institute from 2002 to March 2023. We discussed surgical strategies based on molecular classification. RESULTS Among the cases, there were 34 gliomas and 7 glioneuronal tumors. According to the new WHO classification, they corresponded to 1) Adult-type diffuse gliomas, 2) Pediatric-type diffuse low-grade gliomas, 3) Circumscribed astrocytic tumors, or 4) Glioneuronal and neuronal tumors. Cases without molecular diagnosis were also considered in light of the new WHO classification. DISCUSSION Among molecularly diagnosed astrocytomas involving the cerebral hemisphere, brain stem, spinal cord, there were no cases of 1), and 2) 3) were the main cases. It is important in surgical selection to note that these cases generally have a more favorable prognosis compared to the adult type and have usefulness in diagnosing MAPK pathway abnormalities leading to the selection of molecularly targeted drugs. 3) includes pilocytic astrocytoma, subependymal giant cell astrocytoma, and pleomorphic xanthoastrocytoma. Among these, in the treatment of pilocytic astrocytomas located in the optic pathway and hypothalamus, biopsy becomes necessary for molecular diagnosis and the selection of appropriate therapeutic agents. Conversely, for unilateral optic nerve gliomas, options other than resection may be considered. 4) is primarily associated with epilepsy-related tumors. Surgical resection holds the promise of controlling epilepsy in these cases. However, various genetic abnormalities have been identified, which could prove useful in diagnosis and treatment. CONCLUSION Based on the new WHO classification, a reevaluation of treatment strategies for pediatric brain tumors is necessary.

Leat-associated seizures the possible role of EAAT2, pyruvate carboxylase and glutamine synthetase

BackgroundDrug-resistant epilepsy is a common condition in patients with brain neoplasms. The pathogenesis of tumor-associated seizures is poorly understood. Among the possible pathogenetic mechanisms, the increase in glutamate concentration has been proposed. Glutamate transporters, glutamine synthetase and pyruvate carboxylase are involved in maintaining the physiological concentration of glutamate in the intersynaptic spaces. In our previous research on angiocentric gliomas, we demonstrated that all tumors lacked the expression of the main glutamate transporter EAAT2, while the expression of glutamine synthetase and pyruvate carboxylase was mostly preserved. MethodsIn the present study, we evaluated the immunohistochemical expression of EAAT2, glutamine synthetase and pyruvate carboxylase in a heterogeneous series of 25 long-term epilepsy-associated tumors (10 dysembryoplastic neuroepithelial tumors, 7 gangliogliomas, 3 subependymal giant cell astrocytomas, 3 rosette forming glioneuronal tumors, 1 diffuse astrocytoma MYB- or MYBL1-altered and 1 angiocentric glioma). In order to evaluate the incidence of variants in the SLC1A2 gene, encoding EAAT2, in a large number of central nervous system tumors we also queried the PedcBioPortal. ResultsEAAT2 protein expression was lost in 9 tumors (36 %: 3 dysembryoplastic neuroepithelial tumors, 1 ganglioglioma, 3 subependymal giant cell astrocytomas, 1 diffuse astrocytoma MYB- or MYBL1-altered and 1 angiocentric glioma). Glutamine synthetase protein expression was completely lost in 2 tumors (8 %; 1 ganglioglioma and 1 diffuse astrocytoma MYB- or MYBL1-altered). All tumors of our series but rosette forming glioneuronal tumors (in which neurocytic cells were negative) were diffusely positive for pyruvate carboxylase. Consultation of the PedcBioPortal revealed that of 2307 pediatric brain tumors of different histotype and grade, 20 (< 1%) had variants in the SLC1A2 gene. Among the SLC1A2-mutated tumors, there were no angiocentric gliomas or other LEATs ConclusionsIn conclusion, unlike angiocentric gliomas where the EAAT2 loss is typical and constant, the current study shows the loss of EAAT2 expression only in a fraction of the LEATs. In these cases, we may hypothesize some possible epileptogenic role of the EAAT2 loss. The retained expression of pyruvate carboxylase may contribute to determining a pathological glutamate excess unopposed by glutamine synthetase that resulted expressed to a variable extent in the majority of the tumors. Furthermore, we can assume that the EAAT2 loss in brain tumors in general and in LEATs in particular is more conceivably epigenetic.

Laser interstitial thermal therapy compared with open resection for treating subependymal giant cell astrocytoma.

Subependymal giant cell astrocytomas (SEGAs) are WHO grade 1 tumors associated with tuberous sclerosis that classically arise from the ventricular wall near the caudate groove and foramen of Monro. Laser interstitial thermal therapy (LITT) is a minimally invasive surgical technique, which works by heating a stereotactically placed laser fiber to ablative temperatures under MRI thermometry monitoring. In this paper, the authors present LITT as a surgical alternative to open resection of SEGAs. Twelve patients with SEGAs who underwent 16 procedures between 2007 and 2022 at a single institution were retrospectively reviewed. These patients underwent either open resection or LITT. Clinical data, imaging, recurrence rate, further treatments, and related complications were analyzed. Among the 16 procedures, 9 were open resection and 7 were LITT. An external ventricular drain was placed in 66% (6/9) of open procedures and 57.1% (4/7) of LITT cases. A septostomy was performed in 56% (5/9) of open procedures and 29% (2/7) of LITT cases. Complication rates were higher in open cases than in LITT procedures (44% vs 0%, p < 0.05). Complications included hydrocephalus, transient venous ischemia, wound infection, and bone flap migration. The median length of hospital stay was 4 days (IQR 3.3-5.5 days) for open cases and 4 days (IQR 3.0-7.0 days) for LITT procedures. Recurrence or progression occurred after 3 open cases and 2 LITT cases (33% vs 33%, p = 0.803). For the recurrences, 2 open cases underwent stereotactic radiosurgery, 1 open case underwent LITT, and 1 LITT case underwent repeat LITT. Among the LITT cases, only the patients with no decrease in tumor size by 6 months experienced tumor progression afterward. The 2 LITT cases with progression were the only ones with calcification present on preoperative imaging. The median follow-up times for cases assessed for progression were 8.4 years (IQR 3.8-14.4 years) for open resection and 3.9 years (IQR 3.4-5.1 years) for LITT. The small size of this case series limits generalizability or adequate comparison of safety. However, this series adds to the literature supporting LITT as a less invasive surgical alternative to open resection of SEGAs and demonstrates that LITT has similar recurrence and/or progression rates to open resection. Additional studies with more data are necessary for comprehensive comparisons between open resection and LITT for treating SEGA.

PAEDIATRIC-12 MANAGEMENT OF PAEDIATRIC LOW-GRADE GLIOMA IN CAPE TOWN, SOUTH AFRICA

Abstract OBJECTIVE To assess the management of paediatric low-grade gliomas by the combined neuro-oncology services of the University of Cape Town. METHODS A retrospective analysis was performed on the folders of patients diagnosed at the Red Cross War Memorial Children’s Hospital (RCWMCH) and Groote Schuur Hospital (GSH) between 2000 and 2022. The data includes 2 patient cohorts, the first cohort being patient data collected from 2000-2016 and the second from 2017-2022. RESULTS A total of 127 patients, aged 0.38-13.76 years (mean 5.71) were treated at RCWMCH and GSH. Predisposition syndromes observed included Neurofibromatosis 1 11, Tuberous sclerosis 6, and Trisomy 21 1. The most common sites were the cerebellum 27%, hypothalamus 17%, cerebrum 12%, and optic pathway 13%. Metastatic disease was noted in 12 patients (9%). Gross total resection (or debulking) was performed in 67 (53%) of patients, 40 had biopsy only, and 20 had no surgery (mostly OPGs). Histology was predominantly Juvenile Pilocytic Astrocytoma 70%, Diffuse Astrocytoma 9%, Low-Grade Glioma Nos 8%,5% Subependymal Giant cell Astrocytoma, and 5% Pilomyxoid Astrocytoma. BRAF v600E mutation was tested in 17 patients: all were negative. Forty-four (35%) received chemotherapy and 36 (82%) as first-line therapy with vincristine and carboplatin as the most used agents. Newer therapies Bevacizumab/irinotecan and Trametinib were recently used in 10 patients as third or fourth-line regimens. There was an increase in chemotherapy usage for patients with irresectable tumours between the 2 cohorts, from 27% in the first cohort to 49% in the second. Thirty (23.6%) patients received radiotherapy and of those 8 were in an upfront setting. There was no difference in the 5-year OS between the 2 cohorts, 84% in the first and 85.7% in the second. CONCLUSION Multi-disciplinary treatment of paediatric LGG in LMIC is essential. Patterns of management have changed without affecting outcomes.

Cytological features of diffuse and circumscribed gliomas.

The current World Health Organization classification of gliomas is based on morphological, genetic, and molecular parameters. In this review, we intend to present the most relevant cytological features of these tumours, with a particular focus on their analysis during intraoperative studies. Rapid diagnosis is required in this context, and at present it is not possible to evaluate the genetic or molecular profile of a tumour intraoperatively. New terminology and diagnostic parameters have been introduced, but the essence of intraoperative recognition remains the same. The main challenge in astrocytoma IDH-mutant, grade 2 is recognising the tissue as neoplastic. Since glioma grades 3 and 4 are assigned based on histological and genetic variables that are not necessarily measurable on cytology, the term high-grade glioma is often used for intraoperative diagnosis. Oligodendroglioma, IDH-mutant and 1p/19q-codeleted shows peculiar cytological findings as well as the common subtypes of glioblastoma IDH-wildtype (giant cell, epithelioid, gliosarcoma and small cell). Many of the paediatric-type-diffuse gliomas have been described very recently and there are no cytological reports of proven cases. Finally, pilocytic astrocytoma, pleomorphic xanthoastrocytoma, subependymal giant cell astrocytoma, chordoid glioma, and astroblastoma MN1-altered constitute the group of circumscribed astrocytic gliomas. They are remarkable entities that the pathologist must be able to recognise since most are low-grade neoplasms that can show atypical morphological features.