Medulloblastoma: The Treatment Results and Literature Review

Abstract

Twenty-four children (M:F=13:11) whose ages ranged from 10 months to 13 years (median age 6 years) with histologically confirmed medulloblastomas were treated at Mackay Memorial Hospital from January 1982 to December 1991. All 24 patients were to undergo extensive resection and then to receive a primary course of adjuvant craniospinal axis irradiation with a local posterior fossa boost. The anatomical extent of the disease was classified according to the Chang staging system. Headache, vomiting and an unsteady gait were the major presentations in this series. The overall 5-year survival rate was 58% respectively. In addition, the overall 5-year survival rate was statistically higher in females than in males (73% vs 46%, P=0.03), in early-stage tumors (T1 & T2) than in late-stage tumors (T3 & T4) (71% vs 40%, P=0.066), and in patients who received a dose of 50 Gy or more to the posterior fossa than in those who received a lower dose (73% vs 33%, P=0.05). The extent of surgery had no impact on the survival rate (P=0.13). Patients older than 5-years of age had a higher 5-year survival rate but it was not statistically significant (71% vs 40%, P=0.066). The overall relapse rate was 50% in our series with only 3 eases survived in the follow-up. From the literature review and the results of this series, we can conclude that by more than 50 Gy posterior fossa irradiation, the overall survival rate has much improved, so the late sequellae have become an important subject. However, there is still poor outcome in advanced disease and recurrent disease. The optimal selection criteria are urgently required to reduce long-term complications and to increase survival in poor outcome groups.