Anaplastic astrocytoma neuropath notes

Anaplastic, WHOIII, infiltrating aggressive, normally in cerebral hemispheres
-nuclear atypia, mitoses, high proliferation,
-mean age 45-50,
-Genetics (high tp53 mutation)
-mean time to transition to gbm ~2yrs, EGFr mutations have worse prognosis

Glioblastoma
-most frequent, most malignant brain tumor, WHO IV, can arise de novo or as malignant transformation, very invasive and cannot be fully resected, peak incidence 45-75.
-tumor most likely to be in cerebral hemispheres. however basal ganglia, thalamus, brainstem not uncommon, but see more in children.
-tumor very commonly spreads through corpus callosum, butterfly appearance on imaging
-imaging: ring enhancing, significant edema,
-GBM does not usually go to subarachnoid and so does not show up in CSF, hematogenous spread does not happen (very rare).
- multifocal GBM -true incidence unknown, estimated to be 2.4% of GBM to be multifocal