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Handbook of Clinical Neurology 2016Pilocytic astrocytoma (PA) is the most common pediatric brain tumor in children. PAs are a distinct histologic and biologic subset of glioma that have a slow growth rate... (Review)
Review
Pilocytic astrocytoma (PA) is the most common pediatric brain tumor in children. PAs are a distinct histologic and biologic subset of glioma that have a slow growth rate and may even spontaneously regress. These tumors tend to arise in the cerebellum and chiasmatic/hypothalamic region, but can also occur in other regions of the central nervous system. Dissemination is uncommon, but may occur in newly diagnosed PAs. Alterations in the Ras/RAF/mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) pathway (Ras/ERK) have been discovered in a majority of PAs, with KIAA1549-BRAF fusions being the most commonly identified alteration. Children with neurofibromatosis 1 are predisposed to developing PAs, primarily within the optic pathway. When required, treatment consists of surgery, chemotherapy, and/or radiation, although new molecular agents targeting the Ras/ERK and related signaling pathways are promising new approaches. The 10-year survival rates are greater than 90% in pediatric patients; however, they are poorer in adults. Tumors that are amenable to complete resection (i.e., cerebellum and cortex) have the best overall survival.
Topics: Astrocytoma; Brain Neoplasms; Child; Humans
PubMed: 26948364
DOI: 10.1016/B978-0-12-802997-8.00020-7 -
Current Oncology Reports Mar 2019Temozolomide is a first-line treatment for newly diagnosed glioblastoma. In this review, we will examine the use of temozolomide in other contexts for treating gliomas,... (Review)
Review
PURPOSE OF REVIEW
Temozolomide is a first-line treatment for newly diagnosed glioblastoma. In this review, we will examine the use of temozolomide in other contexts for treating gliomas, including recurrent glioblastoma, glioblastoma in the elderly, diffuse low- and high-grade gliomas, non-diffuse gliomas, diffuse intrinsic pontine glioma (DIPG), ependymoma, pilocytic astrocytoma, and pleomorphic xanthoastrocytoma.
RECENT FINDINGS
Temozolomide improved survival in older patients with glioblastoma, anaplastic gliomas regardless of 1p/19q deletion status, and progressive ependymomas. Temozolomide afforded less toxicity and comparable efficacy to radiation in high-risk low-grade gliomas and to platinum-based chemotherapy in pediatric high-grade gliomas. The success of temozolomide in promoting survival has expanded beyond glioblastoma to benefit patients with non-glioblastoma tumors. Identifying practical biomarkers for predicting temozolomide susceptibility, and establishing complementary agents for chemosensitizing tumors to temozolomide, will be key next steps for future success.
Topics: Antineoplastic Agents, Alkylating; Brain Neoplasms; Evidence-Based Practice; Glioblastoma; Humans; Temozolomide
PubMed: 30835007
DOI: 10.1007/s11912-019-0783-5 -
Neurologic Clinics Aug 2018In the 2016 WHO classification of diffuse glioma, the diagnosis of an (anaplastic) oligodendroglioma requires the presence of both an IDH mutation (mt) and 1p/19q... (Review)
Review
In the 2016 WHO classification of diffuse glioma, the diagnosis of an (anaplastic) oligodendroglioma requires the presence of both an IDH mutation (mt) and 1p/19q codeletion, whereas (anaplastic) astrocytoma are divided in IDH wild-type and IDHmt tumors. Standard of care for grade II and III glioma consists of resection. For patients with tumors that require postoperative treatment, radiotherapy and chemotherapy are recommended. Trials in newly diagnosed grade II and III glioma have shown survival benefit of the addition of chemotherapy to radiotherapy compared with initial treatment with radiotherapy alone; both temozolomide and PCV have been shown to improve survival.
Topics: Astrocytoma; Brain Neoplasms; Humans; Oligodendroglioma
PubMed: 30072066
DOI: 10.1016/j.ncl.2018.04.005 -
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 -
Hematology/oncology Clinics of North... Feb 2022Isocitrate dehydrogenase (IDH) 1 and 2 mutations represent essential components for the diagnosis of diffuse astrocytic tumors and oligodendroglioma. IDH wild-type glial... (Review)
Review
Isocitrate dehydrogenase (IDH) 1 and 2 mutations represent essential components for the diagnosis of diffuse astrocytic tumors and oligodendroglioma. IDH wild-type glial tumors include a wide spectrum of tumors with differences in prognosis and recommended therapeutic approaches. Tumors characterized as molecular glioblastoma in the World Health Organization 2021 classification should be treated according to the glioblastoma therapeutic principles and included in glioblastoma trials. Improving on existing treatments options including targeted and immunotherapy approaches is imperative for most patients with IDH wild-type glial tumors, and enrollment in clinical trials is encouraged.
Topics: Brain Neoplasms; Glioblastoma; Glioma; Humans; Isocitrate Dehydrogenase; Oligodendroglioma
PubMed: 34756799
DOI: 10.1016/j.hoc.2021.08.007 -
Survey of Ophthalmology 2015An 81-year-old woman presented with light perception vision in her left eye and had pallid swelling of the left optic disk. Temporal artery biopsy was normal. Magnetic...
An 81-year-old woman presented with light perception vision in her left eye and had pallid swelling of the left optic disk. Temporal artery biopsy was normal. Magnetic resonance imaging revealed enlargement and enhancement of the left orbital optic nerve. There were vitreous cells, but a vitrectomy specimen showed only a benign lymphocytic population. Her vision deteriorated to no light perception in the left eye, and an optic nerve biopsy revealed a diffuse astrocytoma of World Health Organization grade II.
Topics: Aged, 80 and over; Astrocytoma; Biomarkers, Tumor; Female; Humans; Hypertrophy; Isocitrate Dehydrogenase; Magnetic Resonance Imaging; Optic Nerve; Optic Nerve Neoplasms; Papilledema; Tumor Suppressor Protein p53; Vision Disorders
PubMed: 26079932
DOI: 10.1016/j.survophthal.2015.06.002 -
BMJ Case Reports Aug 2016Psychotic symptoms are rarely documented in association with cortex-sparing central nervous system (CNS) lesions limited to the midbrain. We present the case of a... (Review)
Review
Psychotic symptoms are rarely documented in association with cortex-sparing central nervous system (CNS) lesions limited to the midbrain. We present the case of a 15-year-old boy with hereditary and environmental risk factors for psychiatric illness, as well as a history of midbrain pilocytic astrocytoma treated with chemotherapy and focused radiation, who presented with non-epileptic seizures, hyper-religiosity and frank psychosis. The space-occupying midbrain lesion has been radiographically stable while the patient has decompensated psychiatrically. Differential aetiology for the patient's psychiatric decompensation is discussed, including psychosis secondary to a lesion of the midbrain. Literature linking midbrain lesions to psychotic features, such as in peduncular hallucinosis, is briefly reviewed. This case suggests that a midbrain lesion in a susceptible patient may contribute to psychosis.
Topics: Adolescent; Astrocytoma; Brain Stem Neoplasms; Humans; Male; Psychotic Disorders
PubMed: 27511753
DOI: 10.1136/bcr-2016-216165 -
Cancer Reports (Hoboken, N.J.) Oct 2023A form of cancer called astrocytoma can develop in the brain or spinal cord and sometimes causes death. A detailed overview of the precise signaling cascade underlying... (Review)
Review
BACKGROUND
A form of cancer called astrocytoma can develop in the brain or spinal cord and sometimes causes death. A detailed overview of the precise signaling cascade underlying astrocytoma formation has not yet been revealed, although various factors have been investigated. Therefore, our objective was to unravel and summarize our current understanding of molecular genetics and associated signaling pathways with some possible therapeutic strategies for astrocytoma.
RECENT FINDINGS
In general, four different forms of astrocytoma have been identified in individuals, including circumscribed, diffuse, anaplastic, and multiforme glioblastoma, according to a recent literature review. All types of astrocytoma have a direct connection with some oncogenic signaling cascade. Common signaling is MAPK cascade, including Ras-Raf-ERK, up-regulated with activating EGFR/AKT/PTEN/mTOR and PDGFR. Recent breakthrough studies found that BRAF mutations, including KIAA1549: BRAF and BRAF V600E are responsible for astrocytoma progression. Additionally, cancer progression is influenced by mutations in some tumor suppressor genes, such as the Tp53/ATRX and MGMT mutant. As synthetic medications must cross the blood-brain barrier (BBB), modulating signal systems such as miRNA is the primary option for treating patients with astrocytoma. However, available surgery, radiation therapy, and experimental therapies such as adjuvant therapy, anti-angiogenic therapy, and EGFR-targeting antibody drug are the usual treatment for most types of astrocytoma. Similar to conventional anticancer medications, some phytochemicals slow tumor growth by simultaneously controlling several cellular proteins, including those involved in cell cycle regulation, apoptosis, metastatic spread, tyrosine kinase, growth factor receptor, and antioxidant-related proteins.
CONCLUSION
In conclusion, cellular and molecular signaling is directly associated with the development of astrocytoma, and a combination of conventional and alternative therapies can improve the malignancy of cancer patients.
Topics: Humans; Proto-Oncogene Proteins B-raf; Brain Neoplasms; Astrocytoma; Glioblastoma; ErbB Receptors
PubMed: 37675821
DOI: 10.1002/cnr2.1889 -
Histology and Histopathology Jul 2023According to the fifth edition of the World Health Organization (WHO) Classification, diffuse gliomas typically occurring in adults are classified as oligodendroglioma... (Review)
Review
According to the fifth edition of the World Health Organization (WHO) Classification, diffuse gliomas typically occurring in adults are classified as oligodendroglioma IDH-mutant and 1p/19q codeleted, astrocytoma IDH-mutant, and glioblastoma IDH-wildtype. Among these, the former has the most favorable clinical course, whereas the latter has the worst prognosis. In IDH-mutant gliomas, the IDH1 p. R132H is the most frequent IDH mutation. Other mutations in IDH1 are rare and predominantly found in astrocytomas, whereas IDH2 mutations are mostly observed in oligodendrogliomas. Astrocytomas IDH-mutant display frequent immunohistochemical loss of ATRX, which is mutually exclusive with 1p/19q codeletion. They are graded based on histopathological features and the presence of CDKN2A/B homozygous deletion, whereas the criteria for grading oligodendrogliomas are less defined. DNA methylation profiling has recently shown three additional distinct tumor types among diffuse IDH-mutant gliomas: infratentorial astrocytoma IDH mutant; primary mismatch repair deficient IDH-mutant astrocytoma (PMRDIA); and oligosarcoma. Infratentorial astrocytoma IDH-mutant is enriched in IDH1 or IDH2 mutations that differ from the IDH1 p.R132H mutation and are detectable only by gene sequencing, displays less frequent ATRX loss and MGMT promoter methylation than supratentorial IDH-mutant astrocytomas, and may additionally harbor the H3 K27M mutation, which is typically found in H3 K27-altered diffuse midline glioma. PMRDIA occurs in the context of primary mismatch repair deficiency, is characterized by frequent MSH6 mutations, hypermutation, low frequency of MGMT promoter methylation, and poor clinical outcomes. Finally, oligosarcoma is a tumor featuring oligodendroglial and sarcomatous areas, and is characterized by worse outcome and frequent 1p/19q copy number loss of heterozygosity.
Topics: Adult; Humans; Oligodendroglioma; Homozygote; Sequence Deletion; Glioma; Brain Neoplasms; Astrocytoma; Mutation; Isocitrate Dehydrogenase; Genomics
PubMed: 36651583
DOI: 10.14670/HH-18-582 -
Journal of Neuro-oncology May 2023Astrocytomas and oligodendrogliomas are mainly diffuse primary brain tumors harboring a diagnostic and prognostically favorable isocitrate dehydrogenase mutation. They... (Review)
Review
PURPOSE
Astrocytomas and oligodendrogliomas are mainly diffuse primary brain tumors harboring a diagnostic and prognostically favorable isocitrate dehydrogenase mutation. They are still incurable besides growing molecular knowledge and therapy options. Circumscribed astrocytomas are also discussed here, although they represent a separate entity despite similarities in the nomenclature.
METHODS
We reviewed clinical trials, preclinical approaches as well as guideline recommendations form the major scientific Neuro-Oncology organizations for astrocytomas and oligodendrogliomas according to PRISMA guidelines.
RESULTS
After histopathological diagnosis and eventually a maximal safe resection, patients with good prognostic factors may be followed by magnetic resonance imaging (MRI). If further treatment is necessary, either after diagnosis or at progression, diffuse astrocytomas and oligodendrogliomas are mainly treated with combined radiochemotherapy or maximal safe resection followed by combined radiochemotherapy according to current guidelines based on randomized trials. Circumscribed gliomas like pilocytic astrocytomas, CNS WHO grade 1, or pleomorphic xanthoastrocytomas, CNS WHO grade 2, are often treated with surgery alone. Current approaches for therapy optimization include decision of the best chemotherapy regimen. The IDH mutation presents a rational target for small molecule inhibition and immune therapy in diffuse astrocytomas and oligodendrogliomas, while the BRAF pathway is frequently mutated and treatable in circumscribed gliomas.
CONCLUSION
Despite establishment of standard treatment approaches for gliomas that include resection, radio- and chemotherapy, there is a lack of effective treatments for progressive disease. Immune- and targeted therapies are currently investigated.
Topics: Humans; Oligodendroglioma; Astrocytoma; Glioma; Magnetic Resonance Imaging; Mutation
PubMed: 36566461
DOI: 10.1007/s11060-022-04216-z