Chapter 9: Central Nervous System Cancers

Epidemiology

Work-up

1. Neuroimaging study (MRI of the brain preferred over CT)

   No other staging work-up is required except:

2. Primary CNS lymphoma: MRI of spine, lumbar puncture, and ophthalmologic examination

3. Medulloblastoma: MRI of spine and lumbar puncture when safe to do so

Pathology

1. Neuroepithelial Tumors

   1. Glial tumors (45–50%)

      1. Diffuse astrocytic tumors (75%)

         1. Diffuse astrocytoma (grade II): 20%

            1. Diffuse astrocytoma, IDH-mutant

               • Gemistocytic astrocytoma, IDH-mutant

            2. Diffuse astrocytoma, IDH-wildtype

         2. Anaplastic astrocytoma (AA grade III): 30%

            1. Anaplastic astrocytoma, IDH-mutant

            2. Anaplastic astrocytoma, IDH-wildtype

         3. Glioblastoma (GB, grade IV): 50%

            1. Glioblastoma, IDH-wildtype

               • Giant cell glioblastoma

               • Gliosarcoma: <5% of GB

               • Epithelioid glioblastoma

            2. Glioblastoma, IDH-mutant

         4. Diffuse midline glioma H3 K27M-mutant (grade IV)

      2. Oligodendrogliomas/oligoastrocytomas (5–10%)

         1. Oligodendroglioma (O, grade II)

            1. Oligodendroglioma, IDH-mutant, 1p19q-codeleted

         2. Anaplastic oligodendroglioma (AO, grade III)

            1. Anaplastic oligodendroglioma, IDH-mutant, 1p19q-codeleted

         3. Oligoastrocytoma (OA, grade II)

            1. Oligoastrocytoma NOS (Most OA will fall into this category if molecular testing for oligodendroglioma and astrocytoma is not diagnostic)

            2. Oligoastrocytoma (IDH-mutant, 1p19q-codeleted on oligodendroglioma side, IDH-mutant vs wildtype, 1p19q-intact on astrocytoma side)

         4. Anaplastic oligoastrocytoma (AOA grade III)

            1. Anaplastic oligoastrocytoma NOS (Most AOA will fall into this category if molecular testing for oligodendroglioma or astrocytoma is not diagnostic)

            2. Anaplastic oligoastrocytoma (IDH mutant, 1p19q-codeleted on oligodendroglioma side, IDH-mutant vs wildtype, 1p19q-intact on astrocytoma side)

      3. Other astrocytic tumors (<5%)

         1. Pilocytic astrocytoma (grade I)

         2. Subependymal giant cell astrocytoma (grade I)

         3. Pleomorphic xanthoastrocytoma (grade II)

         4. Anaplastic pleomorphic xanthoastrocytoma (grade III)

      4. Ependymal tumors (5%)

         1. Subependymoma (grade I)

         2. Myxopapillary ependymoma (grade I)

         3. Ependymoma (grade II)

            • Papillary ependymoma

            • Clear cell ependymoma

            • Tanycytic ependymoma

         4. Ependymoma. RELA fusion-positive (grade II or III)

         5. Anaplastic ependymoma (grade III)

   2. Neuronal and mixed glial-neuronal tumors (<1%)

      1. Central neurocytoma (grade II)

      2. Dysembryoplastic neuroepithelial tumor (DNET) (grade I)

      3. Desmoplastic infantile astrocytoma and ganglioglioma (grade I)

      4. Gangliocytoma (grade I)

      5. Ganglioglioma (grade I)

      6. Anaplastic ganglioglioma (grade III)

      7. Dysplastic gangliocytoma of cerebellum (Lhermitte-Duclos disease) (grade I)

      8. Paraganglioma

   3. Nonglial tumors

      1. Embryonal tumors (<5%)

         1. Medulloblastoma (grade IV)

            1. Medulloblastoma, WNT-activated

            2. Medulloblastoma, SHH activated and TP53-mutant

               Medulloblastoma, SHH activated and TP53-wildtype

               Medulloblastoma, non-WNT/non-SHH

            3. Medulloblastoma group 3

            4. Medulloblastoma group 4

         2. CNS neuroblastoma (grade IV)

         3. Atypical teratoid/rhabdoid tumors (AT/RT) (grade IV)

      2. Choroid plexus tumors (<1%)

         1. Choroid plexus papilloma (grade I)

         2. Atypical choroid plexus papilloma (grade II)

         3. Choroid plexus carcinoma (grade III)

      3. Pineal tumors (<1%)

         1. Pineocytoma (grade I)

         2. Pineoblastoma (grade IV)

2. Meningeal Tumors (15–28%)

   1. Meningioma (grade I): (>80–90%)

      1. Secretory meningioma (grade I)

      2. Fibrous meningioma (grade I)

      3. Atypical meningioma (grade II): (10–20%)

      4. Clear cell meningioma (grade II)

      5. Chordoid meningioma (grade II)

      6. Anaplastic (malignant) meningioma (grade III): ...