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Astrocytoma — Clinical Guidelines

Overview

Astrocytomas are tumors originating from astrocytes, ranging from benign to highly malignant forms such as anaplastic astrocytoma and glioblastoma multiforme. These tumors can occur in various brain regions and exhibit diverse biological behaviors and prognoses.

Diagnosis

Immunohistochemical Markers: Expression analysis of DcR3, ERK1/2, and TLR4 can aid in distinguishing glioblastoma from anaplastic astrocytoma 1.

Rapid Techniques: Press preparations are useful for rapid intraoperative pathologic evaluation of fresh tissue from neurosurgical biopsies, maintaining cytologic features and key histologic components 3.

Grading: Diagnosis often involves histopathological examination with grading based on WHO criteria, distinguishing between low-grade (I-II) and high-grade (III-IV) astrocytomas.

Management

Elderly Patients: Hypofractionated radiotherapy (e.g., 15 × 2.66 Gy) is standard, with temozolomide (TMZ) chemotherapy being considered, especially if MGMT promoter is methylated 2.

Chemotherapy: TMZ is beneficial in elderly patients with methylated MGMT promoter 2.

Combination Therapies: Ongoing trials explore combinations like hypofractionated radiotherapy with TMZ or bevacizumab in elderly populations 2.

Special Populations

Elderly: Treatment strategies include hypofractionated radiotherapy and TMZ, with MGMT promoter status influencing chemotherapy efficacy 2.

Comorbidities: Specific management adjustments for comorbidities are not detailed in the provided abstracts.

Key Recommendations

Utilize immunohistochemical markers like DcR3 and TLR4 for differentiating glioblastoma from anaplastic astrocytoma in limited biopsy samples (Evidence: Moderate) 1.

For elderly patients (65+ years), hypofractionated radiotherapy is recommended, with TMZ chemotherapy considered if the MGMT promoter is methylated (Evidence: Strong) 2.

Employ press preparations for rapid intraoperative pathologic assessment of neurosurgical biopsies to facilitate timely diagnosis (Evidence: Moderate) 3.

References

1 Lin CK, Ting CC, Tsai WC, Chen YW, Hueng DY. A tissue microarray study of toll-like receptor 4, decoy receptor 3, and external signal regulated kinase 1/2 expressions in astrocytoma. Indian journal of pathology & microbiology 2016. link 2 Tabatabai G, Stupp R, Wick W, Weller M. Malignant astrocytoma in elderly patients: where do we stand?. Current opinion in neurology 2013. link 3 Kristt DA. Pathologic evaluation of fresh tissue from neurosurgical biopsies: technical and interpretational aspects. Israel journal of medical sciences 1996. link 4 Leese GP, Jung RT, Morley KD. Astrocytoma presenting with vasculitis. Scottish medical journal 1992. link 5 Ardila A, Gómez J. Paroxysmal "feeling of somebody being nearby". Epilepsia 1988. link 6 Sarabia M, Millán JM, Escudero L, Cabello A, Lobato RD. Intracranial seeding from an intramedullary malignant astrocytoma. Surgical neurology 1986. link90343-5) 7 Goetschy JF, Ulrich G, Aunis D, Ciesielski-Treska J. The organization and solubility properties of intermediate filaments and microtubules of cortical astrocytes in culture. Journal of neurocytology 1986. link 8 Naeser P, Möller P. Astrocytoma of the ciliary body. A clinicopathological case report. Acta ophthalmologica 1985. link 9 Smith DA, Lantos PL. Immunocytochemistry of cerebellar astrocytomas: with a special note on Rosenthal fibres. Acta neuropathologica 1985. link 10 Goldman JM, Gazzard BG. Weight loss caused by a thalamic astrocytoma. Gut 1984. link

Astrocytoma