We retrospectively reviewed 15 adult patients (11 males, median age 34 years; range 23-48) who had been treated and followed in our Institution since 1991 from the time of diagnosis until death or last follow-up in December 2001. Headache was the most frequent symptom (93%). The tumor was hemispheric in 11 patients. Complete resection was achieved in eight. CSF in 12 patients and craniospinal MRI in 6 did not show metastatic disease. Two patients refused adjuvant treatment and died with progressive disease. Thirteen patients received adjuvant craniospinal radiotherapy and 11 systemic chemotherapy. After initial treatment only 2 of the 13 patients relapsed in the posterior fossa. Recurrence was probably related to sub-optimal radiotherapy planning: inadequate low dose in the posterior fossa (37.5 Gy) and long delay in initiating treatment. Two of the 13 patients that received adjuvant treatment died: one from meningitis, and one from recurrent disease. Eleven patients remained alive, and disease-free with Karnofsky performance status ranging 80-100. The median overall survival was not reached after a median follow-up of 5.6 years (range 0.7-10.8 years). Estimated 1-, 5- and 10-year overall survival rates were 86.7%, 72.7%, and 72.7%, respectively. Adult medulloblastoma was predominant in males and the majority of patients had hemispheric tumors. Long-term survival was not uncommon. Although chemotherapy may be useful and well tolerated, radiotherapy remains the mainstay adjuvant treatment as suggested by our two recurrences associated with a delay or inadequate dose.