Holocord pilocytic astrocytoma in a young woman with intracranial extension: case report and review of the MRI characteristics.

INTRODUCTION: Pilocytic astrocytoma is a low-grade glioma more frequently seen in patients <20. It is pretty uncommon in the spinal cord. Rarely, astrocytoma may involve the most or total length of the spinal cord; in that case, they are called "holo-cord astrocytoma." In this case report, we are reporting the third holo-cord pilocytic astrocytoma in an adult patient and the first with an extension to the Magendie foramen. CASE PRESENTATION: We presented a 24-year-old woman with complaints of progressively worsening neck and back pain since one year ago. The patient's MRI showed a very large intradural and intramedullary cystic lesion with a solid component within the spinal cord extending from the medulla to the conus medullaris. Partial resection of the solid part of the cervical portion of the tumor was performed. Histopathological evaluation of the resected tumor segments was compatible with grade I pilocytic astrocytoma. After one year of follow-up, neck and back pain has reduced, and neurological functions have improved. CONCLUSION: Spinal cord pilocytic astrocytoma may present as a holo-cord tumor and can rarely extend to the intracranial fossa. Although this tumor does not arise from the central canal, in this case, it was extended through the Magendie foramen. Symptoms could be subtle despite extensive cord involvement. On MRI, this tumor presents as an intramedullary holo-cord cystic lesion intermixed with a solid component with a variable enhancement of the solid component.

Differential tractography and whole brain connectometry in primary motor area gliomas resection: A feasibility study.

OBJECTIVE: Establish the evolution of the connectome before and after resection of motor area glioma using a comparison of connectome maps and high-definition differential tractography (DifT). METHODS: DifT was done using normalized quantitative anisotropy (NQA) with DSI Studio. The quantitative analysis involved obtaining mean NQA and fractional anisotropy (FA) values for the disrupted pathways tracing the corticospinal tract (CST), and white fiber network changes over time. RESULTS: We described the baseline tractography, DifT, and white matter network changes from two patients who underwent resection of an oligodendroglioma (Case 1) and an IDH mutant astrocytoma, grade 4 (Case 2). CASE 1: There was a slight decrease in the diffusion signal of the compromised CST in the immediate postop. The NQA and FA values increased at the 1-year follow-up (0.18 vs. 0.32 and 0.35 vs. 0.44, respectively). CASE 2: There was an important decrease in the immediate postop, followed by an increase in the follow-up. In the 1-year follow-up, the patient presented with radiation necrosis and tumor recurrence, increasing NQA from 0.18 in the preop to 0.29. Fiber network analysis: whole-brain connectome comparison demonstrated no significant changes in the immediate postop. However, in the 1-year follow up there was a notorious reorganization of the fibers in both cases, showing the decreased density of connections. CONCLUSIONS: Connectome studies and DifT constitute new potential tools to predict early reorganization changes in a patient's networks, showing the brain plasticity capacity, and helping to establish timelines for the progression of the tumor and treatment-induced changes.

Intraventricular Pilocytic Astrocytoma in Adults: A 25-year Single-Center Case Series and Systematic Review of the Literature.

BACKGROUND: Pilocytic astrocytomas (PA) are the most common gliomas in children/adolescents but are less common and poorly studied in adults. Here, we describe the clinical presentation, surgical management, and outcomes of surgically treated adult patients with intraventricular (IV) PA and review the literature. METHODS: Consecutive adult patients treated for IV brain tumors at a tertiary academic center over 25 years (1997-2023) were identified. Clinical data were reviewed retrospectively for adult IV PA patients. A systematic literature review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. RESULTS: Eight patients with IV PA were included. Median age was 25 years (range, 18-69 years), and 4 (50%) were female. The most common tumor location was the lateral ventricle (5, 63%), followed by the fourth ventricle (3, 37%). Subtotal and near total resection were the most common surgical outcomes (6 patients, 75%), followed by gross total resection in 2 (25%). Progression or recurrence occurred in 3 patients (37%), requiring repeat resection in 2 patients. The 5-year overall survival and progression-free survival were 67% and 40%, respectively. In addition, 42 cases were identified in the literature. CONCLUSIONS: PAs in adults are rare and an IV location is even more uncommon. The findings demonstrate the challenges in caring for these patients, with overall- and progression-free survival outcomes being poorer than the general adult PA population. Findings support the employment of surgical techniques and approaches that favor gross total resection when possible. Further studies are needed to better characterize this unique presentation.

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 3 years. 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.

Association of Clinical, Tumor, and Treatment Characteristics With Seizure Control in Patients With IDH1/2-Mutant Lower-Grade Glioma.

BACKGROUND AND OBJECTIVES: Patients with IDH1/2-mutant lower-grade glioma have a high frequency of seizures. We aimed to investigate the correlations between seizures and tumor/patient characteristics and the impact of surgery and adjuvant treatments (AT) on seizure control along the disease trajectory. METHODS: We retrospectively included patients with IDH1/2-mutant lower-grade glioma who underwent surgery at the neurosurgery divisions of the University of Turin and Milan and were treated at the Division of Neuro-Oncology of Turin. Inclusion criteria were a diagnosis according to the 2021 WHO Classification and presentation with seizures; exclusion criteria were presence of CDKN2A/B homozygous deletion, intense/ring contrast enhancement on MRI at presentation, and small tissue biopsy. We evaluated seizure freedom for 2 months after surgery, 6 months from starting observation or AT, at recurrence, and for 6 months after treatments of recurrence. RESULTS: We included 150 patients. There were 77 (51%) and 31 (21%) patients with IDH-mutant/1p19q-codeleted grade 2 and 3 oligodendroglioma and 30 (20%) and 12 (8%) with IDH-mutant grade 2 and 3 astrocytoma, respectively. Total resection was accomplished in 68 (45%). Seventy-five patients (50%) received AT while the remaining 75 were observed with MRI. After 6 months after AT, 28 of 29 patients (96.5%) displayed seizure reduction, 5 of 28 (18%) being seizure-free. 66 of 124 patients (53%) had seizures at recurrence. After 6 months after second-line treatments, 60 of 66 patients (91%) had seizure reduction, 11 (17%) being seizure-free. In multivariable analyses, grade 3 histology positively correlated with seizure freedom at 2 months after surgery (OR 3.5, 1.4-8.9, p = 0.008), 6 months after AT (OR 9.0, 1.5-54.9, p = 0.017), and 6 months after treatment of recurrence (OR 4.9, 1.5-16.5, p = 0.009). Adjuvant radiotherapy reduced seizures at recurrence in a univariate analysis (OR 0.14, 0.03-0.7, p = 0.020). Patients with seizure freedom after surgery and AT displayed longer progression-free survival (PFS) (65, 24.5-105, vs 48 months, 32-63.5, p = 0.037). DISCUSSION: This study analyzed seizure control in patients with IDH1/2-mutant lower-grade glioma across multiple time points. Grade 3 correlated with better seizure control throughout the entire disease trajectory, and seizure freedom after surgery and AT correlated with a longer PFS regardless of tumor grade. These results could serve as an external control arm in clinical trials evaluating the efficacy on seizures of antitumor agents in patients with IDH-mutant lower-grade glioma.

A 3-Year-Old Girl with Brain Imaging Findings Suggesting Arachnoid Cyst, and Biopsy Diagnosis of Extra-Axial Multicystic Pilocytic Astrocytoma.

BACKGROUND Arachnoid cysts and pilocytic astrocytomas are distinct intracranial entities with differing clinical presentations, origins, and management strategies. Arachnoid cysts are benign fluid-filled sacs associated with congenital or acquired causes, while pilocytic astrocytomas are low-grade brain tumors, primarily affecting pediatric and young adult populations, originating from astrocytes. However, diagnosing pilocytic astrocytomas can be challenging due to their radiological features, sometimes resembling more common intracranial lesions, such as arachnoid cysts. This case underscores the need for vigilance and a multidisciplinary approach when confronted with neuroimaging findings that diverge from typical patterns. CASE REPORT We present a case of a 3-year-old girl who presented with persistent headaches, vomiting, and difficulty walking. Initial radiological assessment suggested an arachnoid cyst, given the patient's symptoms and imaging characteristics. Subsequently, the patient underwent a craniotomy, with intraoperative findings revealing a cystic lesion without a solid mural nodule, which was excised completely. Postoperatively, histopathological examination confirmed a diagnosis of extra-axial pilocytic astrocytoma. The patient's symptoms resolved, and she was discharged without neurological deficits. CONCLUSIONS Diagnosing extra-axial pilocytic astrocytomas presents challenges, due to their radiological similarities with more common intracranial lesions, like arachnoid cysts. This case underscores the importance of histopathological examination to confirm the diagnosis accurately. Surgical resection remains the primary treatment for extra-axial pilocytic astrocytomas, often resulting in a favorable prognosis.

Resection of an Intradural Intramedullary C7-T1 Tumor: Technical Nuances and Complication Management.

Primary spinal cord tumors are relatively rare, comprising approximately 4%-16% of all tumors originating from the central nervous system. These tumors are anatomically separable into 2 broad categories: intradural intramedullary and intradural extramedullary. Intramedullary tumors are composed predominantly of gliomas (infiltrative astrocytoma) and ependymomas.1-4 The primary treatment approach for these tumors is surgical resection, aiming to preserve neurologic function.5-9 In Video 1, the authors showcase a step-by-step approach for microsurgical resection of a primary spinal ependymoma, with emphasis on microsurgical technique and utility of adjunct equipment, such as intraoperative ultrasound and neuromonitoring.10,11 The patient consented to the procedure.

Epidemiology and Comparative Analysis of Outcomes of Intramedullary Spinal Cord Tumor Between Pediatric and Adult Patients.

STUDY DESIGN: This was as clinical retrospective study. OBJECTIVES: We sought to evaluate the characteristics of Pediatric intramedullary spinal cord tumors (PISCTs) and to identify differences between pediatric and adult intramedullary spinal cord tumors. SUMMARY OF BACKGROUND DATA: PISCTs represent a rare clinical entity with limited evidence-base in the literature. METHODS: This study is a subanalysis of the retrospective multicenter observational study authorized by the Neurospinal Society of Japan, including consecutive patients with spinal intramedullary tumors treated surgically at 58 institutions between 2009 and 2020. Data on 1080 intramedullary spinal cord tumors were obtained, consisting of 91 pediatric and 939 adult patients. Survival was compared using Cox hazard regression while clinical differences were evaluated using multivariable logistic regression that controlled for confounders. RESULTS: Pediatric patients had a shorter overall, and progression-free, survival than adults. Pediatric patients with ISCTs were likely to have scoliosis [odds ratio (OR) = 6.49, 95% CI: 2.26-18.7], short preoperative symptom duration (OR = 0.99, 95% CI: 0.98-0.99), lower incidence of paresthesia (OR = 0.41, 95% CI: 0.22-0.77), higher incidence of paresis (OR = 2.10, 95% CI: 1.01-4.35), histopathology of astrocytoma (OR = 2.97, 95% CI: 1.19-7.43), and postoperative functional deterioration upon discharge (OR = 2.83, 95% CI: 1.43-5.58). Age was not a statistically significant prognostic factor of overall survival among the pediatric cohort. CONCLUSION: We found that the clinical characteristics of ISCTs differed between pediatric and adult patients. In terms of histopathological types, astrocytoma was most common in pediatric patients. ISCT occurring at an early age may not be an indicator for poor prognosis.

What Factors Predict the Development of Neurologic Deficits Following Resection of Intramedullary Spinal Cord Tumors: A Multi-Center Study.

BACKGROUND: Intramedullary spinal cord tumors are challenging to resect, and their postoperative neurological outcomes are often difficult to predict, with few studies assessing this outcome. METHODS: We reviewed the medical records of all patients surgically treated for Intramedullary spinal cord tumors at our multisite tertiary care institution (Mayo Clinic Arizona, Mayo Clinic Florida, Mayo Clinic Rochester) between June 2002 and May 2020. Variables that were significant in the univariate analyses were included in a multivariate logistic regression. "MissForest" operating on the Random Forest algorithm, was used for data imputation, and K-prototype was used for data clustering. Heatmaps were added to show correlations between postoperative neurological deficit and all other included variables. Shapley Additive exPlanations were implemented to understand each feature's importance. RESULTS: Our query resulted in 315 patients, with 160 meeting the inclusion criteria. There were 53 patients with astrocytoma, 66 with ependymoma, and 41 with hemangioblastoma. The mean age (standard deviation) was 42.3 (17.5), and 48.1% of patients were women (n = 77/160). Multivariate analysis revealed that pathologic grade >3 (OR = 1.55; CI = [0.67, 3.58], P = 0.046 predicted a new neurological deficit. Random Forest algorithm (supervised machine learning) found age, use of neuromonitoring, histology of the tumor, performing a midline myelotomy, and tumor location to be the most important predictors of new postoperative neurological deficits. CONCLUSIONS: Tumor grade/histology, age, use of neuromonitoring, and myelotomy type appeared to be most predictive of postoperative neurological deficits. These results can be used to better inform patients of perioperative risk.

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

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

A novel radiological classification of midbrain pilocytic astrocytomas and its implication for surgical management: a single-institution experience of 57 cases.

OBJECTIVE: Surgery for midbrain pilocytic astrocytoma (PA) remains a formidable challenge. To facilitate decision-making and achieve a better outcome in the management of patients with midbrain PA, the authors have proposed a novel radiological classification of midbrain PAs with long-term follow-up. METHODS: Fifty-seven midbrain PA patients who underwent surgery at Beijing Tiantan Hospital, Capital Medical University, from January 2008 to June 2021, were reviewed. Based on tumor location and the topological anatomical change identified on MRI, midbrain PAs were categorized into four types: crural (12/57, 21.1%), tegmental (25/57, 43.9%), aqueductal (5/57, 8.8%), and tectal (15/57, 26.3%) PAs. The relevant clinical, radiological, and pathological data; surgical procedures and results; and long-term outcomes were collected and analyzed. RESULTS: The 1-, 3-, and 5-year survival rates reached 98%, 96%, and 96%, respectively, with gross-total resection achieved in 66.7% of cases, followed by near-total resection in 17.5% cases. The clinical and radiological features, selection of surgical approaches, and long-term postoperative deficits were distinct among each type. Crural PAs were associated with younger age (median 9 years, IQR 5.0-12.8 years); the largest tumor volume (median 31.9 cm3, IQR 17.2-42.6 cm3); the lowest preoperative Karnofsky Performance Scale (KPS) score (median 65, IQR 50-70); the most frequent preoperative motor deficit (91.7%); a mixed solid-cystic component (75%); occupation of the crural cistern; elevation and rotation of the thalamus (medial and/or lateral); displacement of the anterior third ventricle, uncus, and anterior commissure; the most diverse surgical approaches; more frequent use of multimodality image-guided surgery (58.3%); and the most remarkable improvement in KPS score at long-term follow-up. Tegmental PAs were associated with adolescents and young adults (median age 21 years, IQR 8-33 years); tumor volume (median 13.9 cm3, IQR 9.5-20.5 cm3); a good preoperative KPS score (median 80, IQR 70-80); a mixed solid-cystic component (72%); occupation of the ambient cistern and cerebellomesencephalic fissure; a close relationship with the dorsal pons, superior cerebellar peduncle, and posterior inferior third ventricle; and a higher probability of permanent postoperative sensory deficits (40%). Aqueductal and tectal PAs were associated with small tumor volume (median 9.14 cm3, IQR 5.1-17.4 cm3 and median 11.84 cm3, IQR 5.7-18.3 cm3, respectively), a higher percentage of hydrocephalus (80% and 86.7%, respectively), and a straightforward selection of limited surgical approaches. CONCLUSIONS: A novel and comprehensive radiological classification of midbrain PAs was established, which will serve as a valuable tool in patient management and promote uniform communication and comparison across different studies and publications.

Supramaximal resection based on en-bloc technique reduces tumor burden and prolongs survival in primary supratentorial lobar glioblastoma.

PURPOSE: Resection beyond the contrast-enhanced zone contributed to reduce tumor burden and prolong survival in glioblastomas. The optimal extent of resection (EOR) and how to achieve it are worthy of continuous investigation for obtaining a satisfactory balance between maximal resection and the preservation of neurological function. METHODS: A total of 340 adult supratentorial lobar glioblastomas (included astrocytoma, WHO 4, IDH mutation and glioblastoma) were retrospectively evaluated. The clinical data, EOR, technique of resection, postoperative complications, overall survival (OS) and progression-free survival (PFS) were assessed by univariate, multivariate and propensity score matched analysis. Histological staining was performed to comprehend the effect of the membranous structures and the cell distribution in tumoral and peritumoral regions. RESULTS: Supramaximal resection (SMR) was confirmed as resection with 100% EORCE and > 50% EORnCE in glioblastomas by Cox proportional hazards model. Histological results showed SMR reduced the cell density of surgical edge compared to total resection. En-bloc technique based on membranous structures, which had blocking effect on tumoral invasion, contributed to achieve SMR. Moreover, applying en-bloc technique and achieving SMR did not additionally deteriorate neurological function and had similarly effects on the improvement of neurological function. Multivariate analysis confirmed that IDH1 status, technique of resection and EOR were independently correlated with PFS, and > 64 years old, IDH1 status, technique of resection, EOR and preoperative NIHSS were independently correlated with OS. CONCLUSIONS: Applying en-bloc technique and achieving SMR, which could reduce tumor burden and did not increase additional complications, both had remarkedly positive effects on clinical outcomes in patients with primary supratentorial lobar glioblastomas.

Considerations on surgical strategies and associated risk profiles for endoscopic tumor biopsies within the third ventricle and periaqueductal region.

INTRODUCTION: Neuroendoscopic techniques have proven to be a successful and minimally-invasive technique for tumor biopsies within the third ventricle in pediatric patients. However, a comprehensive assessment of associated surgical strategies, techniques, and morbidity is essential to optimize patient outcomes. METHODS: This retrospective study analyzed full endoscopic tumor biopsies in pediatric patients with tumors in the third ventricle and periaqueductal region. Data from 1995 to 2022 were collected from medical records, imaging, and intraoperative video documentation. RESULTS: In this study, 16 shear endoscopic tumor biopsies were performed using the transventricular transforaminal approach. Tumors were located in the anterior or mid part of the third ventricle (50%) or in the periaqueductal and pineal recess region (50%). Preoperative hydrocephalus was seen in 81.25%. Tumor biopsies were harvested successfully in all cases. Simultaneous ETV was performed in 12 (75%) cases and additional septostomy in 3 (18.75%). Significant intraoperative bleeding occurred in 3 cases (18.75%). All bleeding situations could be successfully managed with continuous irrigation. Histopathology revealed astrocytoma as the predominant diagnosis (75%). No new neurologic deficits were observed, except for one case of transient oculomotor nerve paralysis after ETV. Hydrocephalus persisted in 18.6% of all cases with the need of urgent ventriculoperitoneal shunting in two patients. CONCLUSION: In conclusion, neuroendoscopy emerges as an effective technique for tumor biopsies within the third ventricle in pediatric patients, offering the added advantage of simultaneous treatment of obstructive hydrocephalus. However, it is essential to acknowledge the specific intra- and postoperative risks associated with various surgical strategies. The safe management and achievement of favorable clinical results demand extensive experience and expertise.

Supramaximal versus gross total resection in Glioblastoma, IDH wild-type and Astrocytoma, IDH-mutant, grade 4, effect on overall and progression free survival: systematic review and meta-analysis.

PURPOSE: To synthesize the evidence on the impact on progression-free survival (PFS) and overall survival (OS) of supramaximal resection (SMR) over gross total resection (GTR) in Glioblastoma, IDH wild-type and Astrocytoma, IDH-mutant, grade 4 (Glioblastoma). METHODS: The PubMed, Scopus, Web of Science, Ovid and Cochrane databases were systematically searched (up to November 30, 2022). Studies reporting OS and PFS on adult humans with a suspected Glioblastoma, treated either with a SMR or GTR were included. Hazard ratios were estimated for each study and treatment effects were calculated through DerSimonian and Laird random effects models. RESULTS: The literature search yielded 14 studies published between 2013 and 2022, enrolling a total of 6779 patients. Analysis of the included studies reveals significantly better clinical outcomes favoring SMR over GTR in terms of PFS (HR 0.67; p = 0.0007), and OS (HR 0.7; p = 0.0001). CONCLUSION: Glioblastoma, IDH wild-type and Astrocytoma, IDH-mutant, grade 4, are aggressive tumors with a very short long-term OS. SMR is an effective therapeutic approach contributing to increased PFS and OS in patients with this catastrophic disease.

Supratotal Resection: An Emerging Concept of Glioblastoma Multiforme Surgery-Systematic Review And Meta-Analysis.

BACKGROUND: The severe neurologic tumor known as glioblastoma (GBM), also referred to as a grade IV astrocytoma, is rapidly progressive and debilitating. Supratotal resection (SpTR) is an emerging concept within glioma surgery, which aims to achieve a more extensive resection of the tumor than is possible with conventional techniques. METHODS: We performed a language-independent search of PubMed, Scopus, and Cochrane CENTRAL to identify all available literature up to August 2022 of patients undergoing SpTR assessing survival outcomes in comparison to other surgical modalities. RESULTS: After screening for exclusion, a total of 13 studies, all retrospective in design, were identified and included in our meta-analysis. SpTR was associated with significantly increased overall survival (hazard ratio 0.77, 95% CI 0.71-0.84; P < 0.01, I2 = 96%) and progression-free survival (hazard ratio 0.2, 95% CI 0.07-0.56; P = 0.002, I2 = 88%). CONCLUSION: SpTR is associated with greater overall survival and PFS when compared with other glioblastoma surgeries like GTR or SubTR.

Could Fluorescein Staining in Low-Grade Glial Tumors Guide for Peroperative Differentiation of Pathological Types?

AIM: To define whether characteristics of fluorescein staining help to distinguish low grade gliomas intraoperatively. MATERIAL AND METHODS: We studied 46 patients with supratentorial newly diagnosed noncontrast-enhancing LGGs removed by fluorescence guidance under the YELLOW 560 nm filter. Patients who were treated between July 2019 and 2022 were retrospectively analyzed. Clinical data were collected from patient records. Patients? intraoperative video recordings, pathological examination, and preoperative magnetic resonance imaging (MRI) were analyzed and compared for each patient after the operation. Histopathologically, patients were divided into WHO Grade 2 oligodendrogliomas, diffuse astrocytomas (IDH mutant, 1p19q negative tumors), and pre-glioblastomas (IDH wild type, 1p19q negative tumors). Resection margins were checked using controls contrastenhanced cranial MRI at the postoperative 24 and72 hours. RESULTS: Our observations indicate that fluorescein primarily stains diffuse astrocytomas (IDH mutant, 1p19q negative tumors) and pre-glioblastomas (IDH wild type, 1p19q negative tumors) rather than WHO Grade 2 oligodendrogliomas. CONCLUSION: Fluorescein staining might be an option to determine tumor borders in WHO Grade 2 glial tumors, particularly for those with a higher malignancy potential.

A Comparison of Clinical Outcomes for Subependymal Giant Cell Astrocytomas Treated with Laser Interstitial Thermal Therapy, Open Surgical Resection, and mTOR Inhibitors.

INTRODUCTION: Subependymal giant cell astrocytoma (SEGA) is the most common CNS tumor in patients with tuberous sclerosis complex (TSC). Although these are benign, their proximity to the foramen of Monroe frequently causes obstructive hydrocephalus, a potentially fatal complication. Open surgical resection has been the mainstay of treatment; however, this can cause significant morbidity. The development of mTOR inhibitors has changed the treatment landscape, but there are limitations to their use. Laser interstitial thermal therapy (LITT) is an emerging treatment modality that has shown promise in treatment of a variety of intracranial lesions, including SEGAs. We present a single institution, retrospective study of patients treated for SEGAs with LITT, open resection, mTOR inhibitors, or a combination of these modalities. The primary study outcome was tumor volume at most recent follow-up compared with volume at treatment initiation. The secondary outcome was clinical complications associated with treatment modality. METHODS: Retrospective chart review was performed to identify patients with SEGAs treated at our institution from 2010 to 2021. Demographics, treatment information, and complications were collected from the medical record. Tumor volumes were calculated from imaging obtained at initiation of treatment and at most recent follow-up. Kruskal-Wallis nonparametric testing was used to assess differences in tumor volume and follow-up duration between groups. RESULTS: Four patients underwent LITT (3 with LITT only), three underwent open surgical resection, and four were treated with mTOR inhibitors only. Mean percent tumor volume reduction for each group was 48.6 ± 13.8, 90.7 ± 39.8, and 67.1 ± 17.2%, respectively. No statistically significant difference was identified comparing percent tumor volume reduction between the three groups (p = 0.0513). Additionally, there was no statistically significant difference in follow-up duration between groups (p = 0.223). Only 1 patient in our series required permanent CSF diversion and 4 discontinued or decreased the dose of mTOR inhibitor due to either cost or side effects. CONCLUSIONS: Our study suggests that LITT could be considered as a treatment option for SEGAs as it was effective in reducing tumor volume with very few complications. This modality is less invasive than open resection and may be an alternative for patients who are not candidates for mTOR inhibitors. We recommend an updated paradigm for SEGA treatment which includes LITT in select cases after consideration of patient-specific factors.

Radiosurgery outcomes in infratentorial juvenile pilocytic astrocytomas.

PURPOSE: To assess survival and neurological outcomes for patients who underwent primary or salvage stereotactic radiosurgery (SRS) for infratentorial juvenile pilocytic astrocytomas (JPA). METHODS: Between 1987 and 2022, 44 patients underwent SRS for infratentorial JPA. Twelve patients underwent primary SRS and 32 patients underwent salvage SRS. The median patient age at SRS was 11.6 years (range, 2-84 years). Prior to SRS, 32 patients had symptomatic neurological deficits, with ataxia as the most common symptom in 16 patients. The median tumor volume was 3.22 cc (range, 0.16-26.6 cc) and the median margin dose was 14 Gy (range, 9.6-20 Gy). RESULTS: The median follow-up was 10.9 years (range, 0.42-26.58 years). Overall survival (OS) after SRS was 97.7% at 1-year, and 92.5% at 5- and 10-years. Progression free survival (PFS) after SRS was 95.4% at 1-year, 79.0% at 5-years, and 61.4% at 10-years. There is not a significant difference in PFS between primary and salvage SRS patients (p = 0.79). Younger age correlated with improved PFS (HR 0.28, 95% CI 0.063-1.29, p = 0.021). Sixteen patients (50%) had symptomatic improvements while 4 patients (15.6%) had delayed onset of new symptoms related to tumor progression (n = 2) or treatment related complications (n = 2). Tumor volumetric regression or disappearance after radiosurgery was found in 24 patients (54.4%). Twelve patients (27.3%) had delayed tumor progression after SRS. Additional management of tumor progression included repeat surgery, repeat SRS, and chemotherapy. CONCLUSIONS: SRS was a valuable alternative to initial or repeat resection for deep seated infratentorial JPA patients. We found no survival differences between patients who had primary and salvage SRS.