Pediatric Astrocytoma Workup
- Author: Tobey J MacDonald, MD; Chief Editor: Max J Coppes, MD, PhD, MBA more...
The following studies are indicated in patients with suspected astrocytoma:
- Head CT imaging with and without contrast
- CT imaging has higher than 95% sensitivity for the detection of brain tumors.
- On CT scans, most supratentorial low-grade astrocytomas are hypodense with variable contrast enhancement. Calcifications may be present. High-grade tumors show a more heterogeneous density pattern and a more diffuse contrast enhancement.
- Patients with cerebellar astrocytomas may demonstrate hydrocephalus and contrast enhancement on CT scans. A prominent cystic component is often present.
- Brainstem astrocytomas typically enhance poorly after contrast and lack calcifications on CT scans. They may appear isodense or hypodense.
- Head and spine MRI with and without gadolinium
- MRI is the imaging modality of choice for brainstem astrocytomas. See the images shown below.
- MRI of the head must be performed in all patients with CT scan or clinical findings consistent with astrocytoma. Other tumors, such as medulloblastoma and ependymoma, may have a similar appearance on CT scans. MRI is useful in such instances by better demonstrating the anatomic origin and extent of tumor.
- MRI is the imaging modality of choice for detecting primary or disseminated spinal cord lesions. Perform an MRI of the spine in all tumors with malignant characteristics.
- A postoperative MRI is required to measure the extent of surgical resection and the detection of residual disease. Postoperative MRI evaluation must be performed within 72 hours of surgery in order to delineate residual tumor from the postsurgical inflammatory changes that are visualized on MRI at this time.
See the list below:
- CSF cytological examination: This examination is useful in malignant astrocytomas for the detection of microscopic leptomeningeal dissemination.
- Lumbar puncture: CT imaging or MRI must be performed prior to the lumbar puncture (LP) to rule out the presence of hydrocephaly in those patients suspected of having a brain tumor. Hydrocephaly places the patient at risk for herniation as a consequence of the procedure. In general, the LP is deferred as long as 2 weeks postoperatively in order to avoid identifying tumor cells that may have disseminated as a result of surgery.
See the list below:
- Childhood astrocytomas represent different histopathologic entities, such as pure astrocytoma (commonly pilocytic and fibrillary type in children), oligodendroglioma, and mixed tumors of both cell types. Astrocytomas are composed of glial fibrillary acidic protein (GFAP)–positive bipolar or stellate cells. Oligodendrogliomas are characterized by monotonous collections of spheroidal cells. The classification of gliomas is based primarily on their degree of anaplasia, rather than on histologic type.
- Tumors that are modestly cellular and contain few or none of the histologic criteria of malignancy are designated low-grade or grade I and II lesions, according to the WHO. Unifying features are their slowly evolving nonaggressive clinical behavior and relatively benign histological appearance.
- Grade I is primarily designated for the typical pilocytic astrocytoma (see image below), accounting for 85% of cerebellar low-grade gliomas. It is composed of astrocytes interwoven with a fine fibrillary background and often has a characteristic microcystic component and Rosenthal fibers. The newly described pilomyxoid variant of low-grade astrocytoma has unusual histologic features, including abundance of myxoid background, the absence of Rosenthal fibers, and the presence of an angiocentric pattern. Whether or not this is a variant of pilocytic astrocytoma or a distinct entity remains unclear. Grade II is reserved for diffuse astrocytomas composed of moderately cellular astrocytes, oligodendrocytes, or both.
- High-grade tumors are characterized by the presence of several histologic features of malignancy that include hypercellularity, cytologic and nuclear atypia, mitoses, necrosis, and endothelial proliferation (see top image below). These tumors are clinically aggressive, regionally invasive, and capable of neuraxial dissemination. Grade III refers to anaplastic astrocytoma (see top image below) and grade IV is designated for glioblastoma multiforme (see bottom image below).This section displays the high cellularity, mitosis, and nuclear atypia characteristic of an anaplastic astrocytoma (grade III).
- The most common lesions of the brain stem are diffuse intrinsic pontine gliomas (80%). They are not amenable to biopsy except in about 25% of cases, in which an exophytic portion is present. Autopsy reveals that most of these cases are found to be high-grade tumors. Tumors arising in other areas of the brain stem are more likely to be low-grade and may be focal (< 2 cm), cystic, or dorsal exophytic from the floor of the fourth ventricle, or they may arise from the cervicomedullary junction.
See Brain Cancer Staging for summarized information.
Hales RK, Shokek O, Burger PC, Paynter NP, Chaichana KL, Quiñones-Hinojosa A, et al. Prognostic factors in pediatric high-grade astrocytoma: the importance of accurate pathologic diagnosis. J Neurooncol. 2010 Aug. 99(1):65-71. [Medline].
Tihan T, Ersen A, Qaddoumi I, Sughayer MA, Tolunay S, Al-Hussaini M, et al. Pathologic characteristics of pediatric intracranial pilocytic astrocytomas and their impact on outcome in 3 countries: a multi-institutional study. Am J Surg Pathol. 2012 Jan. 36(1):43-55. [Medline].
Leroy HA, Baroncini M, Delestret I, Florent V, Vinchon M. Anorexia: an early sign of fourth ventricle astrocytoma in children. Childs Nerv Syst. 2014 Dec. 30(12):2089-95. [Medline].
Belirgen M, Berrak SG, Ozdag H, Bozkurt SU, Eksioglu-Demiralp E, Ozek MM. Biologic tumor behavior in pilocytic astrocytomas. Childs Nerv Syst. 2012 Mar. 28(3):375-89. [Medline].
Chintagumpala MM, Friedman HS, Stewart CF, et al. A phase II window trial of procarbazine and topotecan in children with high-grade glioma: a report from the children's oncology group. J Neurooncol. 2006 Apr. 77(2):193-8. [Medline].
Geyer JR, Sposto R, Jennings M, et al. Multiagent chemotherapy and deferred radiotherapy in infants with malignant brain tumors: a report from the Children's Cancer Group. J Clin Oncol. 2005 Oct 20. 23(30):7621-31. [Medline].
Pollack IF, Hamilton RL, Sobol RW, et al. O6-methylguanine-DNA methyltransferase expression strongly correlates with outcome in childhood malignant gliomas: results from the CCG-945 Cohort. J Clin Oncol. 2006 Jul 20. 24(21):3431-7. [Medline].
Akyüz C, Demir HA, Varan A, Yalçin B, Kutluk T, Büyükpamukçu M. Temozolomide in relapsed pediatric brain tumors: 14 cases from a single center. Childs Nerv Syst. 2012 Jan. 28(1):111-5. [Medline].
Ait Khelifa-Gallois N, Laroussinie F, Puget S, Sainte-Rose C, Dellatolas G. Long-term functional outcome of patients with cerebellar pilocytic astrocytoma surgically treated in childhood. Brain Inj. 2014 Nov 10. 1-8. [Medline].
Chen L, Du C, Wang L, Yang C, Zhang JR, Li N, et al. Human positive coactivator 4 (PC4) is involved in the progression and prognosis of astrocytoma. J Neurol Sci. 2014 Sep 19. [Medline].
Bouffet E, Jakacki R, Goldman S, et al. Phase II Study of weekly vinblastine in recurrent/refractory pediatric low-grade gliomas. Neuro-Oncology. 2008. 10(3):450.
Bredel M, Pollack IF, Hamilton RL, James CD. Epidermal growth factor receptor expression and gene amplification in high-grade non-brainstem gliomas of childhood. Clin Cancer Res. 1999 Jul. 5(7):1786-92. [Medline].
Cokgor I, Friedman AH, Friedman HS. Gliomas. Eur J Cancer. 1998 Nov. 34(12):1910-5; discussion 1916-8. [Medline].
Fernandez C, Figarella-Branger D, Girard N, et al. Pilocytic astrocytomas in children: prognostic factors--a retrospective study of 80 cases. Neurosurgery. 2003 Sep. 53(3):544-53; discussion 554-5. [Medline].
Finlay JL, Boyett JM, Yates AJ, et al. Randomized phase III trial in childhood high-grade astrocytoma comparing vincristine, lomustine, and prednisone with the eight-drugs-in-1-day regimen. Childrens Cancer Group. J Clin Oncol. 1995 Jan. 13(1):112-23. [Medline].
Finlay JL, Wisoff JH. The impact of extent of resection in the management of malignant gliomas of childhood. Childs Nerv Syst. 1999 Nov. 15(11-12):786-8. [Medline].
Gilbertson RJ, Hill DA, Hernan R, et al. ERBB1 is amplified and overexpressed in high-grade diffusely infiltrative pediatric brain stem glioma. Clin Cancer Res. 2003 Sep 1. 9(10 Pt 1):3620-4. [Medline].
Grill J, Couanet D, Cappelli C, et al. Radiation-induced cerebral vasculopathy in children with neurofibromatosis and optic pathway glioma. Ann Neurol. 1999 Mar. 45(3):393-6. [Medline].
Gururangan S, Fisher MJ, Allen JC, Herndon JE 2nd, Quinn JA, Reardon DA, et al. Temozolomide in children with progressive low-grade glioma. Neuro Oncol. 2007 Apr. 9(2):161-8. [Medline].
Guthrie BL, Laws ER Jr. Supratentorial low-grade gliomas. Neurosurg Clin N Am. 1990 Jan. 1(1):37-48. [Medline].
Huncharek M, Wheeler L, McGarry R, Geschwind JF. Chemotherapy response rates in recurrent/progressive pediatric glioma; results of a systematic review. ALYSIS. 1999 Jul-Aug. 19(4C):3569-74. [Medline].
Jacobson DM. Gliomas of the anterior visual pathways. Neurosurg Clin N Am. 1999 Oct. 10(4):683-98, ix. [Medline].
Khatua S, Peterson KM, Brown KM, et al. Overexpression of the EGFR/FKBP12/HIF-2alpha pathway identified in childhood astrocytomas by angiogenesis gene profiling. Cancer Res. 2003 Apr 15. 63(8):1865-70. [Medline].
Khaw SL, Coleman LT, Downie PA, Heath JA, Ashley DM. Temozolomide in pediatric low-grade glioma. Pediatr Blood Cancer. 2007 Nov. 49(6):808-11. [Medline].
Komotar RJ, Mocco J, Carson BS, et al. Pilomyxoid astrocytoma: a review. MedGenMed. 2004. 6(4):42. [Medline].
Kuo DJ, Weiner HL, Wisoff J, et al. Temozolomide is active in childhood, progressive, unresectable, low-grade gliomas. J Pediatr Hematol Oncol. 2003 May. 25(5):372-8. [Medline].
Lafay-Cousin L, Holm S, Qaddoumi I, et al. Weekly vinblastine in pediatric low-grade glioma patients with carboplatin allergic reaction. Cancer. 2005 Jun 15. 103(12):2636-42. [Medline].
MacDonald TJ, Arenson EB, Ater J, et al. Phase II study of high-dose chemotherapy before radiation in children with newly diagnosed high-grade astrocytoma: final analysis of Children's Cancer Group Study 9933. Cancer. 2005 Dec 15. 104(12):2862-71. [Medline].
Nadkarni TD, Rekate HL. Pediatric intramedullary spinal cord tumors. Critical review of the literature. Childs Nerv Syst. 1999 Jan. 15(1):17-28. [Medline].
Nicholson HS, Krailo M, Ames MM, et al. Phase I study of temozolomide in children and adolescents with recurrent solid tumors: a report from the Children's Cancer Group. J Clin Oncol. 1998 Sep. 16(9):3037-43. [Medline].
Packer RJ. Brain tumors in children. Arch Neurol. 1999 Apr. 56(4):421-5. [Medline].
Pencalet P, Maixner W, Sainte-Rose C, et al. Benign cerebellar astrocytomas in children. J Neurosurg. 1999 Feb. 90(2):265-73. [Medline].
Pollack IF. The role of surgery in pediatric gliomas. J Neurooncol. 1999 May. 42(3):271-88. [Medline].
Pollack IF, Boyett JM, Finlay JL. Chemotherapy for high-grade gliomas of childhood. Childs Nerv Syst. 1999 Oct. 15(10):529-44. [Medline].
Pollack IF, Finkelstein SD, Woods J, et al. Expression of p53 and prognosis in children with malignant gliomas. N Engl J Med. 2002 Feb 7. 346(6):420-7. [Medline].
Prados MD, Edwards MS, Rabbitt J, Lamborn K, Davis RL, Levin VA. Treatment of pediatric low-grade gliomas with a nitrosourea-based multiagent chemotherapy regimen. J Neurooncol. 1997 May. 32(3):235-41. [Medline].
Reddy AT, Packer RJ. Chemotherapy for low-grade gliomas. Childs Nerv Syst. 1999 Oct. 15(10):506-13. [Medline].
Rubin G, Michowitz S, Horev G, et al. Pediatric brain stem gliomas: an update. Childs Nerv Syst. 1998 Apr-May. 14(4-5):167-73. [Medline].
Sharif S, Ferner R, Birch JM, et al. Second primary tumors in neurofibromatosis 1 patients treated for optic glioma: substantial risks after radiotherapy. J Clin Oncol. 2006 Jun 1. 24(16):2570-5. [Medline].
Stupp R, Mason WP, van den Bent MJ, et al. Radiotherapy plus concomitant and adjuvant temozolomide for glioblastoma. N Engl J Med. 2005 Mar 10. 352(10):987-96. [Medline].
Thorarinsdottir HK, Rood B, Kamani N, et al. Outcome for children 111111111111111111Pediatr Blood Cancer</i>. 2006 Feb 2. [Medline].
Vredenburgh JJ, Desjardins A, Herndon JE 2nd, et al. Bevacizumab plus irinotecan in recurrent glioblastoma multiforme. J Clin Oncol. 2007 Oct 20. 25(30):4722-9. [Medline].
Wisoff JH, Boyett JM, Berger MS, et al. Current neurosurgical management and the impact of the extent of resection in the treatment of malignant gliomas of childhood: a report of the Children's Cancer Group trial no. CCG-945. J Neurosurg. 1998 Jul. 89(1):52-9. [Medline].