Medulloblastomas are primitive neuroectodermal tumors that commonly manifest as a posterior fossa mass and obstructive hydrocephalus.
At least four types of molecularly and prognostically distinct medulloblastomas have been identified based on molecular markers. Prognosis varies by type.
Medulloblastomas can disseminate throughout the cerebrospinal fluid (CSF) and should be staged using lumbar puncture and craniospinal imaging to determine the extent of the spread.
Treatment of medulloblastomas depends on the medulloblastoma genotype, patient age, and extent of the spread. Typically in children, maximal safe resection is followed by multidrug chemotherapy in an attempt to avoid radiation therapy (see also Medulloblastomas in children). In adults, surgery is followed by radiation therapy; some data suggest that adding chemotherapy may improve survival.
Image courtesy of William R. Shapiro, MD.
With treatment, survival rates are ≥ 50% at 5 years and about 40% at 10 years.
