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Virchows Archiv : An International... Feb 2023Pilocytic astrocytoma is mostly a pediatric tumor with the majority of patients under age 20. Although tumors can occur throughout neuraxis, most tumors are in the...
Pilocytic astrocytoma is mostly a pediatric tumor with the majority of patients under age 20. Although tumors can occur throughout neuraxis, most tumors are in the cerebellum and optic chiasm. Pilocytic astrocytoma in unusual locations is often associated with different genetic alterations than the classic KIAA1549::BRAF fusion. We report a rare adult pilocytic astrocytoma of the septum pellucidum that presented with progressive headache. A detailed genomic evaluation found a fusion between BRAF and a novel partner RIN2, a gene overexpressed in both low-grade glioma and glioblastoma. The RIN2::BRAF transcript encodes a chimeric protein containing a dimerization domain SH2 and an intact kinase domain, consistent with a prototypic oncogenic kinase rearrangement. In addition, we discuss the potential oncogenic mechanisms of BRAF signaling and its implication in targeted therapy with kinase inhibitors.
Topics: Child; Humans; Young Adult; Astrocytoma; Brain Neoplasms; Carrier Proteins; Glioma; Guanine Nucleotide Exchange Factors; Proto-Oncogene Proteins B-raf; Septum Pellucidum; Signal Transduction; Adolescent
PubMed: 36520196
DOI: 10.1007/s00428-022-03477-3 -
Cancer Sep 1985Cerebral pilocytic astrocytoma is a known intracranial tumor, but its biological characteristics are less well documented. The authors report 30 patients with cerebral...
Cerebral pilocytic astrocytoma is a known intracranial tumor, but its biological characteristics are less well documented. The authors report 30 patients with cerebral pilocytic astrocytoma who were accessioned by the Armed Forces Institute of Pathology between 1970 and 1980. Histological appearance of the tumor was correlated with clinical characteristics. Mean age of onset was 22.15 years, mean preoperative duration of symptoms was 3.77 years, and mean postoperative survival was 5.91 years, with 20 of 23 (87%) known to ultimately survive surgery. These cases of cerebral pilocytic astrocytoma exhibited histologic characteristics consistent with that of a low-grade tumor. Although several of these tumors were of guarded prognosis due to location, degree of infiltration or cyst recurrence, they generally demonstrated a natural course of a relatively low-grade neoplasm.
Topics: Adolescent; Adult; Astrocytoma; Brain Neoplasms; Child; Child, Preschool; Female; Follow-Up Studies; Humans; Infant; Male; Middle Aged; Postoperative Complications; Prognosis
PubMed: 4016701
DOI: 10.1002/1097-0142(19850901)56:5<1128::aid-cncr2820560529>3.0.co;2-j -
Acta Neurochirurgica Oct 2023We describe a 31-year-old male who presented with progressive myelopathy from a thoracic pilocytic astrocytoma (PA). Following multiple recurrences and resections,... (Review)
Review
Malignant transformation of adult-onset pilocytic astrocytoma to diffuse leptomeningeal glioneuronal tumor within the thoracic spine: a case report and review of the literature.
We describe a 31-year-old male who presented with progressive myelopathy from a thoracic pilocytic astrocytoma (PA). Following multiple recurrences and resections, 10 years after his index surgery, pathology revealed diffuse leptomeningeal glioneuronal tumor (DLGNT) with high-grade features. We discuss his clinical course, management, histopathological findings, and present a comprehensive review of spinal PA undergoing malignant transformation in adults and adult-onset spinal DLGNT. To our knowledge, we present the first reported case of adult-onset spinal PA malignant transformation to DLGNT. Our case adds to the paucity of clinical data characterizing such transformations and highlights the importance of developing novel management paradigms.
Topics: Male; Humans; Adult; Meningeal Neoplasms; Central Nervous System Neoplasms; Astrocytoma; Spinal Cord Neoplasms; Spine
PubMed: 36808007
DOI: 10.1007/s00701-023-05529-2 -
Neuro-oncology Sep 2020Pilocytic astrocytoma (PA) is the most common pediatric brain tumor. While genome and transcriptome landscapes are well studied, data of the complete methylome, tumor...
BACKGROUND
Pilocytic astrocytoma (PA) is the most common pediatric brain tumor. While genome and transcriptome landscapes are well studied, data of the complete methylome, tumor cell composition, and immune infiltration are scarce.
METHODS
We generated whole genome bisulfite sequence (WGBS) data of 9 PAs and 16 control samples and integrated available 154 PA and 57 control methylation array data. RNA sequence data of 49 PAs and 11 control samples as well as gene expression arrays of 248 PAs and 28 controls were used to assess transcriptional activity.
RESULTS
DNA-methylation patterns of partially methylated domains suggested high stability of the methylomes during tumorigenesis. Comparing tumor and control tissues of infra- and supratentorial location using methylation arrays revealed a site specific pattern. Analysis of WGBS data revealed 9381 significantly differentially methylated regions (DMRs) in PA versus control tissue. Enhancers and transcription factor (TF) motifs of five distinct TF families were found to be enriched in DMRs. Methylation together with gene expression data-based in silico tissue deconvolution analysis indicated a striking variation in the immune cell infiltration in PA. A TF network analysis showed a regulatory relation between basic leucine zipper (bZIP) transcription factors and genes involved in immune-related processes.
CONCLUSION
We provide evidence for a link of focal methylation differences and differential gene expression to immune infiltration.
Topics: Astrocytoma; Basic-Leucine Zipper Transcription Factors; Child; DNA Methylation; Demethylation; Humans; Immunity
PubMed: 32052037
DOI: 10.1093/neuonc/noaa035 -
Cancer Reports (Hoboken, N.J.) Aug 2022Pilocytic astrocytoma is the most common brain tumour type in childhood located in the posterior fossa, and treated mainly with surgery. These tumours have low...
BACKGROUND
Pilocytic astrocytoma is the most common brain tumour type in childhood located in the posterior fossa, and treated mainly with surgery. These tumours have low mortality, but knowledge concerning its long-term outcome is sparse.
AIMS
The aim was to investigate if patients treated for pilocytic astrocytoma in the posterior fossa had motor complications, including balance, motor and process skills.
METHODS AND RESULTS
This descriptive single-centre study includes eight children and 12 adults, treated for pilocytic astrocytoma as children. Motor performance was investigated with Bruininks-Oseretsky Test of Motor Proficiency, Second Edition, and dynamic balance with the mini-balance evaluation systems test. Physiological cost index, six-minute walk test, hand grip strength and assessment of motor and process skills were also evaluated. Ten patients reported motor difficulties, mainly from the upper limbs. The motor performance test showed results within normal limits except for manual dexterity, which was significantly below mean (p = .008). In the dynamic balance test patients had significantly lower results compared with controls (p = .036). Physiological cost index, six-minute walk tests and hand grip strength showed results within normal limits. In the Assessment of Motor and Process Skills, patients over 16 years had significantly lower results compared with test norms for motor activities of daily living (ADL) and 30% of all patients scored below the cut-off level for difficulties with motor skills.
CONCLUSIONS
Motor performance for patients treated for pilocytic astrocytoma in the posterior fossa in childhood is satisfactory but some patients display difficulties with balance, manual dexterity and ADL motor skills. Thus, it is important to identify those in need of motor follow-up and training.
Topics: Activities of Daily Living; Adult; Astrocytoma; Brain Neoplasms; Child; Hand Strength; Humans
PubMed: 34643060
DOI: 10.1002/cnr2.1548 -
Ryoikibetsu Shokogun Shirizu 2000
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Pediatric Neurosurgery 2019Pilomyxoid astrocytoma (PMA) is a rare brain tumour generally located in the chiasmatic-hypothalamic region. In comparison to pilocytic astrocytoma, PMA has distinct...
Pilomyxoid astrocytoma (PMA) is a rare brain tumour generally located in the chiasmatic-hypothalamic region. In comparison to pilocytic astrocytoma, PMA has distinct histopathological features, aggressive clinical behaviour, a high recurrence rate, and early cerebrospinal fluid dissemination. Only 14 cases of PMA have been reported in the spinal cord since its pathological description in 1999. Here, we report the 15th case in a 3-year-old girl who was treated with chemoradiotherapy and followed up for 5 years. In this report, we also present a review of spinal PMA including treatment options and prognosis.
Topics: Astrocytoma; Chemoradiotherapy, Adjuvant; Child, Preschool; Dose Fractionation, Radiation; Female; Humans; Magnetic Resonance Imaging; Neoplasm Recurrence, Local; Salvage Therapy; Spinal Cord Neoplasms
PubMed: 31593949
DOI: 10.1159/000502615 -
World Neurosurgery Oct 2020Rapid recurrence of a pilocytic astrocytoma with anaplastic transformation is extremely rare. The case of an elderly patient with a cerebellar pilocytic astrocytoma with... (Review)
Review
BACKGROUND
Rapid recurrence of a pilocytic astrocytoma with anaplastic transformation is extremely rare. The case of an elderly patient with a cerebellar pilocytic astrocytoma with anaplastic transformation during short-term follow-up is reported.
CASE DESCRIPTION
An 83-year-old woman presented initially with dizziness and a gait deviation to the right. Magnetic resonance imaging demonstrated a homogeneously enhanced mass in the right cerebellar hemisphere, and the tumor was subtotally removed by right suboccipital craniotomy. Histologic examination showed that the tumor cells contained eosinophilic cytoplasm and spindle-shaped processes with Rosenthal fibers and eosinophilic granular bodies, diagnosed as a typical pilocytic astrocytoma (PA). The MIB-1 index was <1%. The patient did not receive postoperative adjuvant radiation and chemotherapy. Two months after surgery, magnetic resonance imaging showed growth of the residual tumor adjacent to the fourth ventricle, causing obstructive hydrocephalus. She underwent surgery again, and the tumor was totally removed. Histologic findings showed mitotic cells and increased cellularity compared with the primary tumor, which was compatible with anaplastic transformation of PA with a MIB-1 index of 50%. Postoperatively, she was observed with best supportive care without postoperative adjuvant therapy. Nine months after the second operation, she died due to tonsillar herniation and obstructive hydrocephalus caused by a recurrent tumor. An autopsy was performed.
CONCLUSIONS
It is extremely rare, as in the present case, that a cerebellar PA in an elderly patient recurs rapidly with anaplastic transformation, despite deferred postoperative adjuvant therapy including radiation and chemotherapy. A novel molecular-targeted therapy is needed for anaplastic PA showing aggressive biological behavior.
Topics: Aged, 80 and over; Astrocytoma; Cell Transformation, Neoplastic; Cerebellar Neoplasms; Female; Humans; Neoplasm Recurrence, Local
PubMed: 32634636
DOI: 10.1016/j.wneu.2020.06.173 -
Arkhiv Patologii 2022In the latest revisions of the WHO Classification of CNS Tumors, carried out in 2016 and 2021, the traditional histogenetic classification of gliomas is rebuilt on a new... (Review)
Review
In the latest revisions of the WHO Classification of CNS Tumors, carried out in 2016 and 2021, the traditional histogenetic classification of gliomas is rebuilt on a new molecular genetic basis, according to which diffuse midline glioma with alteration of histone H3 K27 is distinguished as a specific pediatric oncosyndrome. The rationale was the association of this feature of midline gliomas in children with a worse prognosis and the prospective possibilities of targeted therapy. A thematic review of the literature and our own observation of H3 K27M-positive glioma in the area of the right thalamus in a 6-year-old child, which initially had the appearance of pilocytic astrocytoma, recurred three times (within 1.5 years) and underwent tumor progression with anaplastic transformation into diffuse glioma of the glioblastoma type, are presented. The authors are inclined to believe that although the determination of the molecular genetic status of H3 K27 provides important information regarding the probable prognosis, at the same time there is no reason to doubt that histological verification should continue to be the basis of oncological diagnosis.
Topics: Child; Humans; Glioblastoma; Brain Neoplasms; Prospective Studies; Mutation; Glioma; Astrocytoma
PubMed: 36469716
DOI: 10.17116/patol20228406140 -
World Neurosurgery Aug 2019Pilocytic astrocytoma is a benign glial tumor typically presenting in children. It is rare for adults to present with pilocytic astrocytoma and even less likely to...
BACKGROUND
Pilocytic astrocytoma is a benign glial tumor typically presenting in children. It is rare for adults to present with pilocytic astrocytoma and even less likely to manifest with multiple foci of lesions especially in nonoptic or hypothalamic locations.
CASE DESCRIPTION
Our patient was a 37-year old man presenting with varied cranial neuropathies, cerebellar dysfunction, and long tract signs, with imaging demonstrating 3 discrete ill-defined contrast-enhancing lesions affecting the cerebellar peduncles, brainstem, and cervicomedullary junction. Neuronavigation-guided biopsy confirmed World Health Organization grade 1 pilocytic astrocytoma; the patient was treated with radiotherapy.
CONCLUSIONS
To our knowledge, we believe this is the first reported case with multifocal infratentorial pilocytic astrocytoma on presentation in an adult patient in the absence of a prior history of associated risk factors such as neurofibromatosis 1 or chemoradiotherapeutic intervention.
Topics: Adult; Astrocytoma; Brain Stem Neoplasms; Cerebellar Neoplasms; Humans; Image-Guided Biopsy; Infratentorial Neoplasms; Magnetic Resonance Imaging; Male; Neoplasms, Multiple Primary; Neuronavigation; Radiotherapy
PubMed: 31082554
DOI: 10.1016/j.wneu.2019.05.006