Pediatric hemispheric cerebellar low-grade gliomas: clinical approach, diagnosis, and management challenges-experience at a tertiary care children's hospital.

PURPOSE: This study aims to provide an exhaustive analysis of pediatric low-grade gliomas (pLGGs) in the cerebellar hemispheres, focusing on incidence, clinical characteristics, surgical outcomes, and prognosis. It seeks to enhance understanding and management of pLGGs in the pediatric population. METHODS: We conducted an observational, descriptive, retrospective, and cross-sectional study at a pediatric hospital, reviewing medical records of 30 patients with cerebellar hemispheric pLGGs treated from December 2014 to January 2023. Data collection included demographics, clinical presentation, imaging findings, surgical approach, postoperative complications, histopathological diagnosis, hydrocephalus management, and follow-up. Molecular markers and adjuvant therapies were also analyzed. RESULTS: The cohort predominantly presented with cerebellar symptoms, with 60% showing hydrocephalus at diagnosis. MRI with gadolinium was crucial for diagnosis. Surgical focus was on achieving gross total resection (GTR), accomplished in 70% of cases. Postsurgical hydrocephalus was less common, and cerebellar mutism was not reported. While a complete molecular analysis was not performed in all cases, available data suggest significant influence of molecular markers on prognosis and therapeutic options of pLGGs. CONCLUSIONS: This study highlights the unique clinical and molecular characteristics of cerebellar hemispheric pLGGs in children. The lower incidence of postoperative hydrocephalus and absence of cerebellar mutism are notable findings. Emphasizing a multidisciplinary approach, our findings contribute to a deeper understanding of pediatric pLGGs, underscoring the need for personalized treatment strategies and vigilant follow-up.

Fluorescein-guided resection for pediatric low-grade gliomas: institutional experience on two cases and a narrative literature review.

PURPOSE: Low-grade gliomas compose 30% of pediatric central nervous system tumors and outcomes of disease-free progression, and survival is directly correlated to the extent of resection. The use of sodium fluorescein (Na-Fl) is an intraoperative method in the localization of tumor cells in adult patients to optimize resection. Our purpose is to describe the use of Na-Fl in pediatric low-grade gliomas and its outcomes. METHODS: Patients under 18 years of age with low-grade gliomas at the author's institution underwent resection with the use of Na-Fl, with review of preoperative imaging findings, intraoperative results, and follow-up. Then, a comprehensive, narrative literature review of the use of Na-Fl in pediatric low-grade glioma was performed. RESULTS: Our single-institution use of Na-Fl in pediatric patients with suspected low-grade glioma demonstrated excellent results of intraoperative enhancement of tumor cells as well as gross total resection. The literature demonstrated 84% Na-Fl staining and 59.2% of gross total resection in pediatric low-grade gliomas with few small case studies, a range of reported findings, and few side effects. CONCLUSION: Na-Fl has a promising use in low-grade glioma resection in the pediatric patient population. Further research is warranted, such as randomized controlled studies, to assess Na-Fl as a potential tool in improving resection and long-term favorable outcomes.

Optimal Combinations of Chemotherapy and Radiotherapy in Low-Grade Gliomas: A Mathematical Approach.

Low-grade gliomas (LGGs) are brain tumors characterized by their slow growth and infiltrative nature. Treatment options for these tumors are surgery, radiation therapy and chemotherapy. The optimal use of radiation therapy and chemotherapy is still under study. In this paper, we construct a mathematical model of LGG response to combinations of chemotherapy, specifically to the alkylating agent temozolomide and radiation therapy. Patient-specific parameters were obtained from longitudinal imaging data of the response of real LGG patients. Computer simulations showed that concurrent cycles of radiation therapy and temozolomide could provide the best therapeutic efficacy in-silico for the patients included in the study. The patient cohort was extended computationally to a set of 3000 virtual patients. This virtual cohort was subject to an in-silico trial in which matching the doses of radiotherapy to those of temozolomide in the first five days of each cycle improved overall survival over concomitant radio-chemotherapy according to RTOG 0424. Thus, the proposed treatment schedule could be investigated in a clinical setting to improve combination treatments in LGGs with substantial survival benefits.

"Next Door" intraoperative magnetic resonance imaging for awake craniotomy: Preliminary experience and technical note.

BACKGROUND: During glioma surgery "maximal safe resection" must be the main goal. Intraoperative magnetic resonance imaging (iMRI) associated with awake craniotomy (AC) is a valuable tool to achieve this objective. In this article, AC with a "next-door" iMRI concept is described in a stepwise protocol. METHODS: This is a retrospective analysis of 18 patients submitted to AC using iMRI; a stepwise protocol is also discussed. RESULTS: The mean age was 41.7 years. Hemiparesis, aphasia, and seizures were the main initial symptoms of the patients. Sixty-six percent of the tumors were located in the left hemisphere. All tumors were near or within eloquent areas. Fifty-three percent of the cases were glioblastomas multiforme and 47% of the patients had low grade gliomas. The mean surgical time and iMRI time were 4 h 4 min and 30 min, respectively. New resection was performed in 33% after iMRI. Extent of resection (EOR) higher than 95% was possible in 66.7% of the patients. The main reason of EOR lower than 95% was positive mapping of eloquent areas (6 patients). Eighty percent of the patients experienced improvement of their deficits immediately after the surgery or had a stable clinical status whereas 20% had neurological deterioration, however, all of them improved after 30 days. CONCLUSION: AC associated with "next-door" iMRI is a complex procedure, but if performed using a meticulous technique, it may improve the overall tumor resection and safety of the patients.

Gross-total resection of temporal low grade gliomas is a critically important factor in achieving seizure-freedom / A ressecção total de gliomas temporais de baixo grau é um importante fator no controle das crises convulsivas

Objective To present a surgical series of patients with low grade temporal gliomas causing intractable epilepsy, focusing on long-term seizure outcome.Method A retrospective study was conducted with patients with temporal low-grade gliomas (LGG).Results Sixty five patients with were operated in our institution. Males were more affected than females and the mean age at surgery was 32.3 ± 8.4 (9-68 years). The mean age at seizure onset was 25.7 ± 9.2 (11-66 years). Seizure outcome was classified according with Engel classification. After one year of follow up, forty two patients (64.6%) were Engel I; seventeen (26.2%) Engel II; four (6.2%) Engel III and two (3.1%) Engel IV. Statistically significant difference in seizure outcome was obtained when comparing the extension of resection. Engel I was observed in 39 patients (69.6%) with total resection and in only 3 (33.3%) patients with partial resection.Conclusion Gross-total resection of temporal LGGs is a critically important factor in achieving seizure-freedom.

Objetivo Apresentar uma série cirúrgica de pacientes com gliomas temporais de baixo grau, causando epilepsia de difícil controle.Método Estudo retrospectivo de pacientes com diagnóstico de glioma temporal de baixo grau temporais.Resultados 65 pacientes com foram operados em nossa instituição. A média de idade de início das crises foi de 25,7 ± 9,2 (11-66 anos). Após um ano de acompanhamento, quarenta e dois pacientes (64,6%) estavam Engel I; dezessete (26,2%) Engel II; quatro (6,2%) Engel III e dois (3,1%) Engel IV. Houve diferença estatisticamente significativa no resultado do controle das crises quando se compara a extensão da ressecção. Engel I foi observada em 39 pacientes (69,6%) com a ressecção total e em apenas 3 (33,3%) pacientes com ressecção parcial.Conclusão A ressecção total de glioma temporal de baixo grau temporais é um fator extremamente importante no controle das crises.

Dysembryoplastic neuroepithelial tumor originally diagnosed as astrocytoma and oligodendroglioma / Tumor neuroepitelial disembrioplásico diagnosticado originalmente como astrocitoma ou oligodendroglioma

Dysembryoplastic neuroepithelial tumor (DNT), described in 1988 and introduced in the WHO classification in 1993, affects predominantly children or young adults causing intractable complex partial seizures. Since it is benign and treated with surgical resection, its recognition is important. It has similarities with low-grade gliomas and gangliogliomas, which may recur and become malignant. OBJECTIVES: To investigate whether DNT was previously diagnosed as astrocytoma, oligodendroglioma, or ganglioglioma and to determine its frequency in a series of low-grade glial/glio-neuronal tumors. METHODS: Clinical, radiological, and histological aspects of 58 tumors operated from 1978 to 2008, classified as astrocytomas (32, including 8 pilocytic), oligodendrogliomas (12), gangliogliomas (7), and DNT (7), were reviewed. RESULTS: Four new DNT, one operated before 1993, previously classified as astrocytoma (3) and oligodendroglioma (1), were identified. One DNT diagnosed in 2002 was classified once more as angiocentric glioma. Therefore, 10 DNT (17.2%) were identified. CONCLUSIONS: Clinical-radiological and histopathological correlations have contributed to diagnose the DNT.

O tumor neuroepitelial disembrioplásico (DNT), descrito em 1988 e incorporado na classificação da OMS em 1993, acomete predominantemente crianças ou adultos jovens, causando crises convulsivas parciais complexas farmacorresistentes. Como é benigno e tratável com ressecção cirúrgica, seu reconhecimento é importante. Tem semelhanças com gliomas de baixo grau e gangliogliomas, que podem recidivar e malignizar. OBJETIVOS: Investigar se o DNT foi originalmente diagnosticado como astrocitoma, oligodendroglioma ou ganglioglioma e determinar sua frequência numa série de neoplasias gliais/glioneuronais de baixo grau. MÉTODOS: Foram revistos aspectos clínicos, radiológicos e histológicos de 58 neoplasias operadas entre 1978 e 2008, classificadas como astrocitomas (32, sendo 8 pilocíticas), oligodendrogliomas (12), gangliogliomas (7) e DNT (7). RESULTADOS: Foram identificados quatro novos DNT, um operado antes de 1993, originalmente diagnosticado como astrocitoma (3) e oligodendroglioma (1). Um DNT diagnosticado em 2002 foi reclassificado como glioma angiocêntrico. Portanto, 10 DNT (17,2%) foram identificados. CONCLUSÕES: Correlações clínico-radiológicas e histopatológicas contribuíram para o diagnóstico do DNT.

Cognitive impairments in patients with low grade gliomas and high grade gliomas / Comprometimentos cognitivos em pacientes com gliomas de baixo grau e gliomas de alto grau

OBJECTIVE: The relationship between brain tumors and cognitive deficits is well established in the literature. However, studies investigating the cognitive status in low and high-grade gliomas patients are scarce, particularly in patients with average or lower educational level. This study aimed at investigating the cognitive functioning in a sample of patients with low and high-grade gliomas before surgical intervention. METHOD: The low-grade (G1, n=19) and high-grade glioma (G2, n=8) patients underwent a detailed neuropsychological assessment of memory, executive functions, visuo-perceptive and visuo-spatial abilities, intellectual level and language. RESULTS: There was a significant impairment on verbal and visual episodic memory, executive functions including mental flexibility, nominal and categorical verbal fluency and speed of information processing in G2. G1 showed only specific deficits on verbal and visual memory recall, mental flexibility and processing speed. CONCLUSION: These findings demonstrated different levels of impairments in the executive and memory domains in patients with low and high grade gliomas.

OBJETIVO: A associação entre tumores cerebrais e déficits cognitivos é bem estabelecida na literatura. No entanto, estudos sobre a cognição de pacientes com gliomas de baixo e alto grau são escassos, especialmente, em sujeitos com baixa escolaridade. Este estudo investigou o funcionamento cognitivo de uma amostra de pacientes com gliomas de baixo e alto grau antes da intervenção cirúrgica. MÉTODO: Os pacientes com glioma de baixo grau (G1, n=19) e alto grau (G2, n=8) foram avaliados quanto à memória, funções executivas, habilidades visuo-perceptivas e visuo-espaciais, nível intelectual e linguagem. RESULTADOS: Houve prejuízo significativo em G2 na memória episódica verbal e visual, funções executivas incluindo flexibilidade mental, fluência verbal nominal e categórica e velocidade de processamento de informações. G1 demonstrou apenas déficits específicos de evocação verbal e visual, flexibilidade mental e velocidade de processamento. CONCLUSÃO: Estes achados demonstraram níveis diferenciados de comprometimento nos domínios executivos e mnésticos de pacientes com gliomas de baixo e alto grau.