the who 2000 tumor classification - Radiology - Uniformed Services ...

USU – Learning to Care for Those in Harm’s WayWHO Gr1 - Pilocytic AstrocytomaUSU – Learning to Care for Those in Harm’s WayWHO Gr1 - Pilocytic AstrocytomaRadiology - http://rad.usuhs.eduRadiology - http://rad.usuhs.eduCircumscribed Mass:Fluid-secretingCyst w/NodulePushing MarginASTROCYTOMA:Circumscribed• “Special” Astrocytomas• Astrocytoma of Young• Various Locations• Well circumscribed (yet, no capsule)• Do NOT spread along WM• Do NOT change grade (except PXA)PILOCYTIC ASTROCYTOMACystic Cerebellar AstrocytomaJuvenile Pilocytic Astrocytoma(“PA” or “JPA”)• Constellation of findings correlates w/ HistologyPILOCYTIC ASTROCYTOMAUSU – Learning to Care for Those in Harm’s WayPilocytic Astrocytoma• Synonyms: Polar Spongioblastoma, , Cystic CerebellarAstrocytoma• Cell of Origin: Astrocyte (bi-polar,hairlike)• Associations: in ON w/ NF-1• Incidence: 3-6% 3of ALL Cranial, 32% of Child• Age: 5-15 (Zulch(3-7)Sex: Slight F (11/9)• Location: Cerebellum, Chiasm/HypothalHypothal, , Optic• Treatment: Surgery, patience• Prognosis: 77% at 5 yrs, 75% at 10 yrs, 75% at 15 yrsRadiology - http://rad.usuhs.eduCyst and Mural Nodule– balanced morphology• Wall may not enhance• Cyst fluid has protein– Not identical to CSF• Nodule low density on CT– may calcify up to 25%• No increase in vascularity• WHO Grade 1• Peak at ~10 yrs