Astrocytoma other diagnostic studies

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Fahimeh Shojaei, M.D.

Overview

Biopsy is helpful in the diagnosis of astrocytomas. Findings suggestive diagnostic of astrocytoma include normal cells with slow growth rate, biphasic pattern (dense fibrillar tissue within loose myxoid tissue), Calcification, Vascular hyalinization and Nested fibrotic pattern in pilocytic astrocytoma, atypical cells, relatively slow mitosis rate, diffusely infiltrate neuropil and poorly defined cytoplasm in diffuse astrocytoma, pleomorphic and malignant cells, High mitosis rate, hyperchromatosis and prominent small vessels in anaplastic astrocytoma, Pleomorphic cells, Naked nuclei, Multi-focal necrosis, Pseudopalisading pattern, Scattered pyknotic nuclear debris in the center, Micro-vascular proliferation and Vascular thrombi in glioblastoma multiform.

Biopsy is helpful in the diagnosis of astrocytomas:^[1]^[2]^[3]

Astrocytomas are histologically heterogenous.
Obtaining small specimen from astrocytomas might lead to false diagnosis.
For lesions with areas of contrast enhancement the specimen should be obtained from those areas.
For lesions with no intra-tumor enhancement the specimen should be obtained from the center of the tumor.

Pathological findings diagnostic of astrocytoma include:^[4]^[5]^[6]

Pilocytic:
- Cells appearance is normal and growth rate is slow.
- Biphasic pattern (dense fibrillar tissue within loose myxoid tissue)
- Calcification
- Vascular hyalinization
- Nested fibrotic pattern
Diffuse:
- There might be some atypical cells inside tumor.
- Mitosis rate is relatively slow.
- Diffusely infiltrate neuropil
- Poorly defined cytoplasm
Anaplastic:
- Tumor cells are pleomorphic and malignant
- High mitosis rate
- Hyperchromatosis
- Prominent small vessels
Glioblastoma:
- Pleomorphic cells
- Naked nuclei
- Multi-focal necrosis
- Pseudopalisading pattern
- Scattered pyknotic nuclear debris in the center
- Micro-vascular proliferation
- Vascular thrombi

Molecular findings diagnostic of astrocytoma include:^[7]

• Stem cell
• Precursor cell
• Glial cell

IDH1 mutation

• 10q loss
• PTEN mutation
• EGFR overexpression
• MDM2 overexpression

• KIAA1549-BRAF fusion
• MAPK/ERK abnormalities

• p53 mutation
• PDGF/PDGFRA overexpression

Primary glioblastoma grade IV

Pilocytic astrocytoma grade I

Diffuse astrocytoma grade II

Chr 19q loss

Anaplastic astocytoma grade III

10q loss

Glioblastoma (secondary) grade IV

↑ Jackson RJ, Fuller GN, Abi-Said D, Lang FF, Gokaslan ZL, Shi WM, Wildrick DM, Sawaya R (July 2001). “Limitations of stereotactic biopsy in the initial management of gliomas”. Neuro-oncology. 3 (3): 193–200. doi:10.1093/neuonc/3.3.193. PMC 1920616. PMID 11465400.
↑ McGirt MJ, Villavicencio AT, Bulsara KR, Friedman AH (April 2003). “MRI-guided stereotactic biopsy in the diagnosis of glioma: comparison of biopsy and surgical resection specimen”. Surg Neurol. 59 (4): 277–81, discussion 281–2. PMID 12748009.
↑ Son BC, Kim MC, Choi BG, Kim EN, Baik HM, Choe BY, Naruse S, Kang JK (2001). “Proton magnetic resonance chemical shift imaging (1H CSI)-directed stereotactic biopsy”. Acta Neurochir (Wien). 143 (1): 45–9, discussion 49–50. PMID 11345717.
↑ Mattle, Heinrich (2017). Fundamentals of neurology : an illustrated guide. Stuttgart New York: Thieme. ISBN 9783131364524.
↑ Nafussi, Awatif (2005). Tumor diagnosis : practical approach and pattern analysis. London New York: Arnold Distributed in the U.S.A. by Oxford University Press. ISBN 0340809442.
↑ Schniederjan, Matthew (2011). Biopsy interpretation of the central nervous system. Philadelphia: Wolters Kluwer/Lippincott Williams & Wilkins Health. ISBN 9780781799935.
↑ Ellison, David (2013). Neuropathology : a reference text of CNS pathology. Edinburgh New York: Mosby. ISBN 0723435154.