-
Operative Neurosurgery (Hagerstown, Md.) Jun 2022
Topics: Astrocytoma; Brain Stem Neoplasms; Humans
PubMed: 35383702
DOI: 10.1227/ons.0000000000000157 -
Neurosurgical Review Feb 2020Pilocytic astrocytomas (PAs) are benign glial tumors and one of the most common childhood posterior fossa tumors. Spontaneous intratumoral hemorrhage in PAs occurs... (Review)
Review
Pilocytic astrocytomas (PAs) are benign glial tumors and one of the most common childhood posterior fossa tumors. Spontaneous intratumoral hemorrhage in PAs occurs occasionally, in about 8-20% of cases. Cerebellar hemorrhages in pediatric population are rare and mainly due to head injuries, rupture of vascular malformations, infections, or hematological diseases. We have investigated the still controversial and unclear pathophysiology underlying intratumoral hemorrhage in PAs. Bleeding in low-grade tumors might be related to structural abnormalities and specific angio-architecture of tumor vessels, such as degenerative mural hyalinization, "glomeruloid" endothelial proliferation, presence of encased micro-aneurysms, and glioma-induced neoangiogenesis. The acute hemorrhagic presentation of cerebellar PA in childhood although extremely uncommon is of critical clinical importance and necessitates promptly treatment. We described a case of hemorrhagic cerebellar PA in a 9-year-old child and reviewed the English-language literature that reported spontaneous hemorrhagic histologically proven cerebellar PA in pediatric patients (0-18 years). According to our analysis, the mortality was not related to symptom onset, tumor location, hemorrhage distribution, presence of acute hydrocephalous, and timing of surgery, while the GCS at hospital admission resulted to be the only statistically significant prognostic factor affecting survival outcome. The abrupt onset of signs and symptoms of acute hydrocephalous and consequent raised intracranial pressure are life-threatening conditions, which need emergent medical and neurosurgical treatments. At a later time, the identification of posterior fossa hemorrhage etiology is crucial to select the appropriate treatment and address the surgical strategy, optimizing the postoperative results.
Topics: Astrocytoma; Cerebellar Neoplasms; Cerebral Hemorrhage; Child; Humans; Male
PubMed: 29569086
DOI: 10.1007/s10143-018-0969-6 -
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 -
Journal of Clinical Neuroscience :... Nov 2014This clinical series examines the presentation of three adult patients who were found to have de novo anaplastic pilocytic astrocytoma. Initial imaging demonstrated an...
This clinical series examines the presentation of three adult patients who were found to have de novo anaplastic pilocytic astrocytoma. Initial imaging demonstrated an intracranial mass with histological analysis diagnostic of pilocytic astrocytoma with anaplastic features including necrosis, marked nuclear pleomorphism and a very high mitotic rate leading to the diagnosis of anaplastic pilocytic astrocytoma. We discuss the clinical pitfalls, treatment and implications when managing this condition.
Topics: Adult; Astrocytoma; Brain; Female; Humans; Immunohistochemistry; Magnetic Resonance Imaging; Male; Mitotic Index; Necrosis; Neoplasm Grading; Neurofibromatoses; Papilledema
PubMed: 24954244
DOI: 10.1016/j.jocn.2014.02.014 -
Child's Nervous System : ChNS :... May 2020
Topics: Astrocytoma; Child; Humans; Imidazoles; Oximes
PubMed: 32002607
DOI: 10.1007/s00381-020-04527-4 -
Neurological Sciences : Official... Jul 2022Pilocytic astrocytoma (PA) rarely spreads along neuraxis, and association with superficial siderosis (SS) and chronic signs of intracranial hypertension is exceptional.
BACKGROUND
Pilocytic astrocytoma (PA) rarely spreads along neuraxis, and association with superficial siderosis (SS) and chronic signs of intracranial hypertension is exceptional.
CASE REPORT
A 48-year-old woman presented with slow onset hearing loss in the past year. Clinical examination revealed dysarthria, positive Romberg test, and severe optic neuropathy. Cerebrospinal fluid (CSF) analysis showed numerous red blood cells, increased proteins and LDH, and high opening pressure. Brain and spine MRI demonstrated extensive superficial siderosis, bone remodeling of the skull base and spine, and diffuse nodular leptomeningeal enhancement. Histological examination of a nodule in the dorsal spine evidenced PA.
CONCLUSION
We report a case of PA associated with dural remodeling and SS. The mechanism of SS is unclear but might be related to meningeal tumor infiltration and altered CSF composition and resorption.
Topics: Astrocytoma; Brain; Female; Humans; Intracranial Hypertension; Magnetic Resonance Imaging; Middle Aged; Siderosis
PubMed: 35460451
DOI: 10.1007/s10072-022-06077-w -
Cellular and Molecular Life Sciences :... Jun 2012Pilocytic astrocytoma (PA) is the most common tumor of the pediatric central nervous system (CNS). A body of research over recent years has demonstrated a key role for... (Review)
Review
Pilocytic astrocytoma (PA) is the most common tumor of the pediatric central nervous system (CNS). A body of research over recent years has demonstrated a key role for mitogen-activated protein kinase (MAPK) pathway signaling in the development and behavior of PAs. Several mechanisms lead to activation of this pathway in PA, mostly in a mutually exclusive manner, with constitutive BRAF kinase activation subsequent to gene fusion being the most frequent. The high specificity of this fusion to PA when compared with other CNS tumors has diagnostic utility. In addition, the frequency of alteration of this key pathway provides an opportunity for molecularly targeted therapy in this tumor. Here, we review the current knowledge on mechanisms of MAPK activation in PA and some of the downstream consequences of this activation, which are now starting to be elucidated both in vitro and in vivo, as well as clinical considerations and possible future directions.
Topics: Animals; Astrocytoma; Disease Models, Animal; Gene Fusion; Humans; MAP Kinase Signaling System; Mice; Models, Genetic; Neurofibromin 1; Proto-Oncogene Proteins B-raf
PubMed: 22159586
DOI: 10.1007/s00018-011-0898-9 -
Journal of Neuro-oncology Jan 2021The aim of this study was to understand the use of chemotherapy (CMT) and radiotherapy (RT) in pilocytic astrocytoma (PA) and their impact on overall survival (OS). (Review)
Review
PURPOSE
The aim of this study was to understand the use of chemotherapy (CMT) and radiotherapy (RT) in pilocytic astrocytoma (PA) and their impact on overall survival (OS).
METHODS
Data from the National Cancer Database (NCDB) for patients with non-metastatic WHO grade I PA from 2004 to 2014 were analyzed. Pearson's chi-squared test and multivariate logistic regression analyses were performed to assess the distribution of demographic, clinical, and treatment factors. Inverse probability of treatment weighting (IPTW) was used to account for differences in baseline characteristics. Kaplan-Meier analyses and doubly-robust estimation with multivariate Cox proportional hazards modeling were used to analyze OS.
RESULTS
Of 3865 patients analyzed, 294 received CMT (7.6%), 233 received RT (6.0%), and 42 (1.1%) received both. On multivariate analyses, decreasing extent of surgical resection was associated with receipt of both CMT and RT. Brainstem tumors were associated with RT, optic nerve tumors were associated with CMT. Cerebellar tumors were inversely associated with both CMT and RT. Younger age was associated with receipt of CMT; conversely, older age was associated with receipt of RT. After IPTW, receipt of CMT and/or RT were associated with an OS decrement compared with matched patients treated with surgery alone or observation (HR 3.29, p < 0.01).
CONCLUSIONS
This is the largest study to date to examine patterns of care and resultant OS outcomes in PA. We identified patient characteristics associated with receipt of CMT and RT. After propensity score matching, receipt of CMT and/or RT was associated with decreased OS.
Topics: Adult; Astrocytoma; Chemoradiotherapy; Child; Humans; Prognosis
PubMed: 33131004
DOI: 10.1007/s11060-020-03653-y -
Seminars in Pediatric Neurology Mar 2015Pilocytic astrocytoma (PA) is the most common astrocytic neoplasm of childhood. Patients have an extremely favorable prognosis after surgical resection, qualifying... (Review)
Review
Pilocytic astrocytoma (PA) is the most common astrocytic neoplasm of childhood. Patients have an extremely favorable prognosis after surgical resection, qualifying tumors for a grade I designation by the World Health Organization. The molecular data on PA support a key role for the BRAF oncogene in the pathogenesis of these tumors, with the KIAA1549-BRAF fusion being the most common alteration identified in sporadic cases, particularly those occurring in the posterior fossa. Constitutive activation of BRAF leads to downstream activation of the MEK/MAPK/ERK/p16 pathway, which interestingly is also used by cells to activate oncogene-induced senescence (OIS). In fact, the presence of an active OIS pathway might explain the periods of dormancy or spontaneous regression or both, that can be seen in PA. In addition to reviewing the historical evolution, clinicopathologic, predictive, prognostic, and molecular features of PA, we discuss current therapeutic strategies and the caveats that should be considered for the development of therapies that could be used to more effectively treat challenging cases. Individualized treatment requires identification of the type of MAPK alteration, as several alterations in BRAF have been described in addition to the KIAA1549-BRAF fusion. Combination regimens would also appear crucial to achieve tumor eradication and prevent the development of drug resistance. Balancing mitogen-activated protein kinases (MAPK) pathway inhibition with abrogation of an active OIS should be carefully considered as well to preserve any existing protective pathways. Importantly, PAs are largely indolent tumors, and care should be taken to avoid overtreatment, as aggressive therapy could cause more harm than good.
Topics: Astrocytoma; Central Nervous System Neoplasms; Genetic Testing; Humans
PubMed: 25976257
DOI: 10.1016/j.spen.2014.12.001 -
International Journal of Radiation... Oct 2012To determine the patient, tumor, and treatment characteristics of patients with pilocytic astrocytoma (PA) and leptomeningeal dissemination (LMD). (Review)
Review
PURPOSE
To determine the patient, tumor, and treatment characteristics of patients with pilocytic astrocytoma (PA) and leptomeningeal dissemination (LMD).
METHODS AND MATERIALS
A PubMed search of English-language studies pertaining to PA with LMD was performed using a combination of keywords that included juvenile pilocytic astrocytoma, low-grade astrocytoma, low-grade glioma, leptomeningeal dissemination, neuraxis spread, and radiotherapy. We found 26 studies with 58 patients between 1976 and 2005 that met these criteria.
RESULTS
The median survival for PA patients with LMD was 65 months. The 1-, 2-, and 5-year overall survival (OS) rate after the diagnosis of LMD was 81.1%, 75.7%, and 55.5%. The 1-, 2-, and 5-year progression-free survival (PFS) rate after the diagnosis of LMD was 69.3%, 66.5%, and 34.6%, respectively. Age, gender, primary site location, timing of LMD presentation (synchronous vs. metachronous), and LMD location did not significantly influence OS or PFS. No statistically significant difference was found in OS or PFS between the chemotherapy and radiotherapy groups. Likewise, no difference was found in OS or PFS according to the use of craniospinal irradiation vs. less extensive RT fields.
CONCLUSIONS
Approximately one-half of PA patients were alive 5 years after the diagnosis of LMD. Both chemotherapy and radiotherapy have efficacy against LMD. Although the use of craniospinal irradiation did not have an effect on PFS, the patient numbers were small and a larger number treated with craniospinal irradiation is needed to determine its efficacy.
Topics: Adolescent; Adult; Astrocytoma; Brain Neoplasms; Child; Child, Preschool; Combined Modality Therapy; Diagnostic Imaging; Female; Humans; Infant; Male; Meningeal Neoplasms; Neoplasm Invasiveness; Survival Analysis; Young Adult
PubMed: 22401918
DOI: 10.1016/j.ijrobp.2011.12.044