University:
Coventry University
Course:
B940 | Biomedical Science
Academic year:

2023
Views:

281

Pages:

3
Author:

Badusha S.

OLIGODENDROGLIOMA (Grade 11/10) 5-150% of Enliomas 40-50 Molecular genetics mutation in IDHI & IDH-2 (90%) Better Prognosis. Loss of 9p, loss of 109, mutation in CDKN2A MORPHOLOGY Gross Site Common in white matter of Corebral Hemisphere Well-circumscribed. gelatinous, grey show cyst - areas of Hemorrhage, calcification MICROSCOPY Shapes of small, round, regular cells Nuclei spherical nuclei within fine granular chromatin Cytoplasm Nuclei surrounded by clear halo of Cytoplasm giving rise to fried-egg appearance to the cell. Stroma delicate Network of anastomosing. Capillaries (chicken-wire app) Calcification common - Mitotic figure is not seen // Prognosis: Better than astrocytomas // PILOCYTIC ASTROCYTOMA ✓ Relatives benign excellent Prognosis/... -Diff. based on other types of astrocytoma & this gross) & (microscopic appearance Site Cerebellem, Flor, walls of third-ventricle, optic nerve./ CROSS usual cystic or solid and well-circumscribed Microscops show biphasic pattern Fibrillary areas composed of bipolor astrocytes with abundant long, this hair-like glial process GFAP (+) Loose microcystic areas cells contain Rosenthal Fibres and eosinophilic granular Bodies. • Do not show infiltration into surrounding brain EPENDYMOMA Tumor arising form opendymal cells, line the central Canal of spinel cord. Children Sites: First 2 decades of Life 4 4 Ventricl Adults: Spinel cord MICROSCOPY Tumor cells Resemble normal ependymal cells • Cells are regular having well-defined cell-membrane 0 Nuclei Round to oval having granular chromatin • Variable amount of dense-fibrillary- background Rossettes Ependymal rosettes: Tumour cells may form gland-like round or elongated structures which resemble embrabolic epend ma Conal Perivascular pseudorosettes - Tumour cells are arranged arround vessels. Special stain PTAH -positive blepharoplasts (Basal bodies of cile of ependymal canal Immunohis to chemist → GFAP (+) Poon prognosis