How often does medulloblastoma recur?

Doctors currently treat medulloblastomas with surgery, followed by radiation and chemotherapy. Although these treatment methods are effective, the cancer may come back after treatment in up to one-third of children with medulloblastoma. Doctors may utilize an MRI scan to detect any residual cancer cells, although these scans cannot pick up on small traces of such cells. Oftentimes, scar tissue from surgery and radiation can appear to look just like the tumor. For this reason, routine spinal taps, where a needle is inserted between two lower vertebrae to collect cerebrospinal fluid, may be administered to detect small traces of residual cancer cells in the CSF.