Pediatric cerebellar pilomyxoid astrocytoma: Clinical and radiological findings in three cases

Ghassen Gader; Ghassen Belkahla; Nadhir Karmani; Khalil Saadaoui; Mouna Rkhami; Jalel Kallel; Ihsèn Zammel; Mohamed Badri

doi:10.4103/ajns.AJNS_268_19

Asian Journal of Neurosurgery, Table of Contents

CC BY-NC-ND 4.0 · Asian J Neurosurg 2020; 15(02): 262-265
DOI: 10.4103/ajns.AJNS_268_19

Review Article

Pediatric cerebellar pilomyxoid astrocytoma: Clinical and radiological findings in three cases

Authors

Ghassen Gader

Department of Neurosurgery, Trauma and Burns Center, Ben Arous
Ghassen Belkahla

Department of Neurosurgery, Trauma and Burns Center, Ben Arous
Nadhir Karmani

¹Department of Neurosurgery, National Institute of Neurology, Tunis
Khalil Saadaoui

²Department of Neurosurgery, Universitary Hospital of Sahloul, Sousse
Mouna Rkhami

Department of Neurosurgery, Trauma and Burns Center, Ben Arous
Jalel Kallel

¹Department of Neurosurgery, National Institute of Neurology, Tunis
Ihsèn Zammel

Department of Neurosurgery, Trauma and Burns Center, Ben Arous
Mohamed Badri

Department of Neurosurgery, Trauma and Burns Center, Ben Arous

Abstract

Pilomyxoid astrocytomas (PMA) is a particular form of glial tumors distinct from pilocytic astrocytomas (PA). On the last 2016 WHO classification for CNS tumours, no definite grade assignment was proposed for these lesions. They may be more aggressive with a different clinical course compared to PA due to their greater propensity for local recurrence and cerebrospinal dissemination. Most cases arise from the hypothalamic region. Only few studies reported cerebellar localization of the lesion. We report 3 pediatric cases treated for pediatric PMA of the posterior fossa. Clinical, radiological, and prognostic features were reviewed. The age of our patients was between 1 and 9 years old. Signs of intracranial hypertension were found in all patients. One of them presented an increased head circumference and the 2 others had a cerebellar syndrome. Brain CT-scan and MRI displayed a large wellcircumscribed intra-axial solid and cystic posterior fossa tumor. Total surgical resection was performed for all tumors. After a 2 years follow up, no signs of recurrence were noticed. In the literature, PMA been reported with overwhelming majority in children aged between 2 months and 4 years. Despite of many pathological similarities with PAs, PMAs have some specific features in histology, leading to their identification as independent type of glioma. Radiological differential diagnosis between PMAs and Pas can be made using arterial spin labeling imaging, which shows low perfusion parameters in PAs. Clinical and radiological follow up are mandatory do to different natural history and higher rates of local recurrence of this tumor compared to PA. Prognosis is favorable when complete surgical exeresis is possible.

Key-words:

Astrocytoma - neurosurgery - pediatrics

Full Text

References

References
1 Jänisch W, Schreiber D, Martin H, Gerlach H. Diencephalic pilocytic astrocytoma with clinical onset in infancy. Biological behavior and pathomorphological findings in 11 children. Zentralbl Allg Pathol 1985;130:31-43.
2 Tihan T, Burger PC. A variant of pilocytic astrocytoma: A possible distinct clinicopathological entity with a less favorable outcome. J Neuropathol Exp Neurol 1998;57:500.
3 Louis DN, Ohgaki H, Wiestler OD, Cavenee WK, Burger PC, Jouvet A, et al. The 2007 WHO classification of tumours of the central nervous system. Acta Neuropathol 2007;114:97-109.
4 Komotar RJ, Burger PC, Carson BS, Brem H, Olivi A, Goldthwaite PT, et al. Pilocytic and pilomyxoid hypothalamic/chiasmatic astrocytomas. Neurosurgery 2004;54:72-9.
5 Ge PF, Wang HF, Qu LM, Chen B, Fu S, Luo Y. Pilomyxoid astrocytoma in cerebellum. Chin J Cancer Res 2011;23:242-4.
6 Forbes JA, Mobley BC, O'Lynnger TM, Cooper CM, Ghiassi M, Hanif R, et al. Pediatric cerebellar pilomyxoid-spectrum astrocytomas. J Neurosurg Pediatr 2011;8:90-6.
7 Morales H, Kwock L, Castillo M. Magnetic resonance imaging and spectroscopy of pilomyxoid astrocytomas: Case reports and comparison with pilocytic astrocytomas. J Comput Assist Tomogr 2007;31:682-7.
8 Linscott LL, Osborn AG, Blaser S, Castillo M, Hewlett RH, Wieselthaler N, et al. Pilomyxoid astrocytoma: Expanding the imaging spectrum. AJNR Am J Neuroradiol 2008;29:1861-6.
9 Buccoliero AM, Gheri CF, Maio V, Moncini D, Castiglione F, Garbini F, et al. Occipital pilomyxoid astrocytoma in a 14-year-old girl-case report. Clin Neuropathol 2008;27:373-7.
10 Alimohamadi M, Bidabadi MS, Ayan Z, Ketabchi E, Amirjamshidi A. Pilomyxoid astrocytoma with involvement of the sella turcica in an adolescent. J Clin Neurosci 2009;16:1648-9.
11 Komotar RJ, Mocco J, Zacharia BE, Wilson DA, Kim PY, Canoll PD, et al. Astrocytoma with pilomyxoid features presenting in an adult. Neuropathology 2006;26:89-93.
12 Sajadi A, Janzer RC, Lu TL, Duff JM. Pilomyxoid astrocytoma of the spinal cord in an adult. Acta Neurochir (Wien) 2008;150:729-31.
13 Komakula ST, Fenton LZ, Kleinschmidt-DeMasters BK, Foreman NK. Pilomyxoid astrocytoma: Neuroimaging with clinicopathologic correlates in 4 cases followed over time. J Pediatr Hematol Oncol 2007;29:465-70.
14 Koeller KK, Rushing EJ. From the archives of the AFIP: Pilocytic astrocytoma: Radiologic-pathologic correlation. Radiographics 2004;24:1693-708.
15 Arslanoglu A, Cirak B, Horska A, Okoh J, Tihan T, Aronson L, et al. MR imaging characteristics of pilomyxoid astrocytomas. AJNR Am J Neuroradiol 2003;24:1906-8.
16 Yeom KW, Mitchell LA, Lober RM, Barnes PD, Vogel H, Fisher PG, et al. Arterial spin-labeled perfusion of pediatric brain tumors. AJNR Am J Neuroradiol 2014;35:395-401.
17 Bing F, Kremer S, Lamalle L, Chabardes S, Ashraf A, Pasquier B, et al. Value of perfusion MRI in the study of pilocytic astrocytoma and hemangioblastoma: Preliminary findings. J Neuroradiol 2009;36:82-7.
18 Skovrlj B, Pain M, Bederson JB, Fowkes M. Pilomyxoid astrocytoma of the cerebellar vermis in an elderly patient. Surg Neurol Int 2014;5:29.