Tumors recur when all the tumor cells cannot be removed by surgery or killed by other treatments. In children, medulloblastoma tends to “seed” or drop tumor cells into the spinal fluid. These cells can give rise to tumor growth in the spine. This type
of spread may or may not be accompanied by tumor regrowth in the cerebellum. In adults, the tumor tends to first regrow in the cerebellum. On very rare occasions, the tumor may spread elsewhere in, and outside, of the central nervous system.
Recurring medulloblastoma is treated aggressively with repeated surgery, re-irradiation if possible, and chemotherapy. Recurrences limited to the cerebellum (the posterior fossa) offer the best chance of long-term survival since treatment can
be aimed at the “local” site. Surgery or radiation therapy focused on the regrowth may be a choice.
Chemotherapy may be of benefit if the tumor spreads beyond the local area. If chemotherapy was not used for the initial tumor, it may now be a consideration. Patients who previously received chemotherapy can be given different drugs for the recurrence. High-dose chemotherapy may be considered, as might a clinical trial investigating new therapies.