Medulloblastoma

• Tumor of very primitive, undifferentiated cells that can differentiate along neural lines or glial lines

• This is a tumor of kids

• Named based on where it is

  • If it’s in the cerebellum-midline, it’s a medulloblastoma

  • If it’s in the adrenal medulla, it’s a neuroblastoma

  • If it’s in the eye it’s a retinoblastoma

  • If it’s anywhere else it’s a primitive neural ectodermal tumor (PNET)

• Can get into CSF and invade meninges

• Looks like small oat cell carcinoma of the lung

• Sheets of anaplastic cells, abundant mitoses

• Can form pseudo-rosettes (Homer-Wright rosettes)

• Can be treated decently with chemo and surgery (~75% 5YS)

• Grossly they are big, hemorrhagic, mushy messes and may appear slightly cystic (include pilocytic astrocytoma in the differential)

Category: Pathology Notes