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Journal of Child Neurology Oct 2020Pilocytic astrocytomas are the primary tumors most frequently found in children and adolescents, accounting for approximately 15.6% of all brain tumors and 5.4% of all... (Review)
Review
Pilocytic astrocytomas are the primary tumors most frequently found in children and adolescents, accounting for approximately 15.6% of all brain tumors and 5.4% of all gliomas. They are mostly found in infratentorial structures such as the cerebellum and in midline cerebral structures such as the optic nerve, hypothalamus, and brain stem. The present study aimed to list the main characteristics about this tumor, to better understand the diagnosis and treatment of these patients, and was conducted on search of the published studies available in NCBI, PubMed, MEDLINE, Scielo, and Google Scholar. It was possible to define the main histologic findings observed in these cases, such as mitoses, necrosis, and Rosenthal fibers. We described the locations usually most affected by tumor development, and this was associated with the most frequent clinical features. The comparison between the molecular diagnostic methods showed great use of fluorescent in situ hybridization, polymerase chain reaction (PCR), and reverse transcriptase-PCR, important techniques for the detection of mutation and fusion, characteristic molecular alterations in pilocytic astrocytomas.
Topics: Astrocytoma; Brain Neoplasms; Humans; In Situ Hybridization, Fluorescence; Polymerase Chain Reaction
PubMed: 32691644
DOI: 10.1177/0883073820937225 -
International Journal of Molecular... Nov 2020Astrocytomas and, in particular, their most severe form, glioblastoma, are the most aggressive primary brain tumors and those with the poorest vital prognosis. Standard... (Review)
Review
Astrocytomas and, in particular, their most severe form, glioblastoma, are the most aggressive primary brain tumors and those with the poorest vital prognosis. Standard treatment only slightly improves patient survival. Therefore, new therapies are needed. Very few risk factors have been clearly identified but many epidemiological studies have reported a higher incidence in men than women with a sex ratio of 1:4. Based on these observations, it has been proposed that the neurosteroids and especially the estrogens found in higher concentrations in women's brains could, in part, explain this difference. Estrogens can bind to nuclear or membrane receptors and potentially stimulate many different interconnected signaling pathways. The study of these receptors is even more complex since many isoforms are produced from each estrogen receptor encoding gene through alternative promoter usage or splicing, with each of them potentially having a specific role in the cell. The purpose of this review is to discuss recent data supporting the involvement of steroids during gliomagenesis and to focus on the potential neuroprotective role as well as the mechanisms of action of estrogens in gliomas.
Topics: Animals; Astrocytoma; Disease Progression; Female; Hormones; Humans; Male; Models, Biological; Receptors, Steroid; Sex Characteristics
PubMed: 33266110
DOI: 10.3390/ijms21239114 -
MedGenMed : Medscape General Medicine Dec 2004Pilomyxoid astrocytoma (PMA) is a recently described type of brain tumor. PMA shares similar features with pilocytic astrocytoma (PA), the most common central nervous... (Review)
Review
Pilomyxoid astrocytoma (PMA) is a recently described type of brain tumor. PMA shares similar features with pilocytic astrocytoma (PA), the most common central nervous system (CNS) tumor in the pediatric population, yet displays subtle histologic differences. Previous studies have shown PMA to behave more aggressively than PA, with shorter progression-free and overall survival as well as a higher rate of recurrence and CNS dissemination. These findings suggest that PMA may be a unique and distinct neoplasm. This review summarizes the histologic, clinical, and radiographic characteristics of PMA. In addition, the current treatment options and research endeavors involving this disease are described. Increased recognition of PMA within the medical community has the potential to affect the treatment and prognosis of pediatric low-grade astrocytomas.
Topics: Astrocytoma; Brain; Brain Neoplasms; Humans; Radiography
PubMed: 15775869
DOI: No ID Found -
World Neurosurgery Jun 2019Intramedullary glial neoplasms affecting the entire spinal cord from the cervicomedullary junction to conus medullaris are termed holocord tumors. Pilocytic astrocytomas... (Review)
Review
BACKGROUND
Intramedullary glial neoplasms affecting the entire spinal cord from the cervicomedullary junction to conus medullaris are termed holocord tumors. Pilocytic astrocytomas are relatively uncommon tumors forming holocord involvement. Hitherto 24 holocord astrocytoma cases were reported in the literature. Here, a case of an adult holocord pilocytic astrocytoma was presented.
CASE DESCRIPTION
A 29-year-old female patient presented with a subtotal resection. Histopathologic examination revealed pilocytic astrocytoma, World Health Organization grade 1, presenting holocord involvement. Magnetic resonance imaging showed a mass containing necrotic and cystic foci leading to an expansion along the entire spinal cord extending from C4 to conus medullaris.
CONCLUSIONS
Reported holocord pilocytic astrocytomas in the relevant literature cases were reviewed. When evaluating magnetic resonance imaging scans of adult patients with various neurologic symptoms, i.e., weakness and fecal and urinary incontinence, pilocytic astrocytoma should be considered among differential diagnoses of intramedullary mass lesions.
Topics: Adult; Astrocytoma; Female; Humans; Spinal Cord; Spinal Cord Neoplasms
PubMed: 30902768
DOI: 10.1016/j.wneu.2019.03.103 -
Neurology India 2022Intraventricular pilocytic astrocytomas are a rare occurrence, accounting for approximately 4% -15.6% of all pilocytic astrocytomas .The aim of the study was to describe...
BACKGROUND
Intraventricular pilocytic astrocytomas are a rare occurrence, accounting for approximately 4% -15.6% of all pilocytic astrocytomas .The aim of the study was to describe the radiology, surgical management and outcome in 15 patients with histopathologically proven intraventricular pilocytic astrocytoma(IVPA).
OBJECTIVE
To study the clinical presentation radiology and operative challenges in rare intra ventricular pilocytic astrocytomas.
MATERIALS AND METHODS
Between January 2010 and August 2018, 15 patients with histopathologically proven IVPA were identified. The radiological images were obtained from PACS. Patient and surgical details were obtained from the computerized discharge summary, OT records and operative notes, whereas follow up was obtained from the record section.
RESULTS
Headache with progressive loss of vision was the most common presentation. Duration of symptoms varied from 4 months to 2 years (mean 9. 88 months). Except one patient, all patients with preoperative CT scan revealed calcifications in the lesion, with extensive calcification in 3 patients. All the tumors were predominantly hypointense on T1WI and iso to hyperintense on T2WI. Lesion in all patients showed heterogenous contrast enhancement on post gadolinium images. Mean blood loss in the series was 1969 ml (range 250 ml- 4500 ml).There was one death in this series due to meningitis and septic shock.
CONCLUSION
IVPAs are rare tumors and are difficult to diagnose in the preoperative period based on the radiologic profile alone. These tumors can be extremely vascular with potential for massive blood loss. These tumors can be associated with extensive calcification and the calcified tumors have less bleeding as expected.
Topics: Astrocytoma; Brain Neoplasms; Calcinosis; Gadolinium; Humans; Tomography, X-Ray Computed
PubMed: 36076645
DOI: 10.4103/0028-3886.355185 -
Clinical and Translational Medicine Feb 2024Paediatric and adult astrocytomas are notably different, where clinical treatments used for adults are not as effective on children with the same form of cancer and... (Review)
Review
Paediatric and adult astrocytomas are notably different, where clinical treatments used for adults are not as effective on children with the same form of cancer and these treatments lead to adverse long-term health concerns. Integrative omics-based studies have shown the pathology and fundamental molecular characteristics differ significantly and cannot be extrapolated from the more widely studied adult disease. Recent clinical advances in our understanding of paediatric astrocytomas, with the aid of next-generation sequencing and epigenome-wide profiling, have led to the identification of key canonical mutations that vary based on the tumour location and age of onset. These driver mutations, in particular the identification of the recurrent histone H3 mutations in high-grade tumours, have confirmed the important role epigenetic dysregulations play in cancer progression. This review summarises the current updates of the classification, epidemiology, pathogenesis and clinical management of paediatric astrocytoma based on their grades and the ongoing clinical trials. It also provides novel insights on genetic and epigenetic alterations as diagnostic biomarkers, highlighting the potential of targeting these pathways as therapeutics for this devastating childhood cancer.
Topics: Adult; Humans; Child; Brain Neoplasms; Astrocytoma; Histones; Epigenesis, Genetic; Epigenomics
PubMed: 38299304
DOI: 10.1002/ctm2.1560 -
Neuro-oncology Jan 2015Despite 6 decades of research, only 3 drugs have been approved for astrocytomas, the most common malignant primary brain tumors. However, clinical drug development is... (Review)
Review
Despite 6 decades of research, only 3 drugs have been approved for astrocytomas, the most common malignant primary brain tumors. However, clinical drug development is accelerating with the transition from empirical, cytotoxic therapy to precision, targeted medicine. Preclinical animal model studies are critical for prioritizing drug candidates for clinical development and, ultimately, for their regulatory approval. For decades, only murine models with established tumor cell lines were available for such studies. However, these poorly represent the genomic and biological properties of human astrocytomas, and their preclinical use fails to accurately predict efficacy in clinical trials. Newer models developed over the last 2 decades, including patient-derived xenografts, genetically engineered mice, and genetically engineered cells purified from human brains, more faithfully phenocopy the genomics and biology of human astrocytomas. Harnessing the unique benefits of these models will be required to identify drug targets, define combination therapies that circumvent inherent and acquired resistance mechanisms, and develop molecular biomarkers predictive of drug response and resistance. With increasing recognition of the molecular heterogeneity of astrocytomas, employing multiple, contemporary models in preclinical drug studies promises to increase the efficiency of drug development for specific, molecularly defined subsets of tumors.
Topics: Animals; Antineoplastic Agents; Astrocytoma; Brain Neoplasms; Cell Line, Tumor; Disease Models, Animal; Drug Discovery; Glioblastoma; Humans; Mice
PubMed: 25246428
DOI: 10.1093/neuonc/nou288 -
CNS Oncology Apr 2017Astrocytomas are responsible for 30% of all primitive intramedullary tumors with cervicothoracic predominance. However, only about one hundred cases of intramedullary... (Review)
Review
Astrocytomas are responsible for 30% of all primitive intramedullary tumors with cervicothoracic predominance. However, only about one hundred cases of intramedullary pilocytic astrocytomas were described. The authors described the case of a 69 year-old patient presenting with a broad-base gait, bilateral pain and dysesthesia of inferior limbs with a diagnosis of an intra-axial cystic lesion centered to the conus medullaris, diagnosed as pilocytic astrocytoma of conus medullaris (PACM) after surgery. To the best of our knowledge, only two previous reports concerning PACM were made. As benign lesions associated with long survivals, function should be the mainstay of treatment of PACM. Surgical resection should be performed. Adjuvant radiotherapy or chemotherapy has no establish role in pilocytic astrocytic lesions.
Topics: Aged; Astrocytoma; Female; Humans; Magnetic Resonance Imaging; Spinal Cord; Spinal Cord Neoplasms
PubMed: 28425761
DOI: 10.2217/cns-2016-0030 -
The Lancet. Neurology Jul 2003Because of its unpredictable clinical course, treatment strategies for low-grade (grade II) astrocytoma vary from "wait and see" to gross tumour resection followed by... (Review)
Review
Because of its unpredictable clinical course, treatment strategies for low-grade (grade II) astrocytoma vary from "wait and see" to gross tumour resection followed by immediate radiotherapy. Clinical studies on grade II astrocytoma show that 5-year-survival ranges from 27% to 85% of patients with very few consistent prognostic variables besides the patient's age and the presence of neurological deficit. There is no universally recognised choice of therapy for patients with astrocytoma grade II, partly because of the shortcomings of histological classification systems. Routine microscopy tends to underestimate malignancy grading of astrocytomas and in most cases cannot distinguish between indolent and progressive subtypes. Recent studies suggest that proliferation and genetic markers can be used to identify subgroups of astrocytoma grade II with a rapid progressive clinical course. Therefore these markers should be included in ongoing and future clinical studies of patients with astrocytoma grade II.
Topics: Adult; Age Factors; Astrocytoma; Cell Transformation, Neoplastic; Disease Progression; Humans; Middle Aged; Mutation; Prognosis; Supratentorial Neoplasms; Treatment Outcome
PubMed: 12849117
DOI: 10.1016/s1474-4422(03)00434-4 -
Journal of Neuropathology and... Jun 2018The histological and molecular features and even the mere existence of diffuse astrocytoma, IDH-wildtype, remain unclear. We therefore examined 212 diffuse astrocytomas...
The histological and molecular features and even the mere existence of diffuse astrocytoma, IDH-wildtype, remain unclear. We therefore examined 212 diffuse astrocytomas (grade II WHO) in adults using IDH1(R132H) immunohistochemistry followed by IDH1/IDH2 sequencing and neuroimaging review. DNA methylation status and copy number profiles were assessed by Infinium HumanMethylation450k BeadChip. Only 25/212 patients harbored tumors without IDH1/IDH2 hotspot mutations and without contrast enhancement. By DNA methylation profiling, 10/25 tumors were classified as glioblastoma, IDH-wildtype, and an additional 7 cases could not be classified using methylome analysis, but showed genetic characteristics of glioblastoma. Histologically, all of these 17 tumors were low-grade diffuse astrocytomas. Nevertheless, 10/17 patients experienced early malignant progression. Other methylation classes included diffuse midline glioma, H3 K27M-mutant, diffuse astrocytoma, IDH-mutant, pilocytic astrocytoma, and normal or reactive brain tissue (total n = 8). In conclusion, no convincing diffuse astrocytoma, IDH-wildtype, was identified. Most IDH-wildtype tumors showing histopathological and radiological features of low-grade diffuse astrocytoma exhibit molecular and clinical features of high-grade glioma and may represent an early stage of primary glioblastoma. Our findings have implications for the biology, classification and neuropathological diagnosis of diffuse astrocytoma, IDH-wildtype in adults.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Astrocytoma; Brain Neoplasms; DNA Methylation; Disease Progression; Female; Glioblastoma; Humans; Immunohistochemistry; Isocitrate Dehydrogenase; Male; Middle Aged; Molecular Diagnostic Techniques; Mutation; Young Adult
PubMed: 29444314
DOI: 10.1093/jnen/nly012