The Treatment of Adults with Medulloblastoma: a Prospective Study

Purpose: To assess in a prospective trial the value of prognostic factors and the outcome of medulloblastoma in adults.

Methods And Materials: Patients (> or =18 years) with a histologic diagnosis of medulloblastoma were staged according to Chang et al.'s classification (low risk: T1, T2, T3a, M0, and no residual disease after surgery; high risk: T3b-T4, any M+ or postoperative presence of residual tumor). In low-risk patients, treatment consisted of 36 Gy to the craniospinal axis, supplemented by a local tumor dose of 18.8 Gy (total dose of 54.8 Gy). In high-risk patients, 2 cycles of "up-front chemotherapy" were delivered before the same radiation therapy, followed by maintenance chemotherapy if M1, M2, or M3 disease was present.

Results: Over a 12-year period, 36 evaluable patients were enrolled. Progression-free survival (PFS) at 5 years was higher in low-risk patients compared to the high-risk group: 76% +/- 14% (95% confidence interval [CI] = 52%-100%) vs. 61% +/- 11% (95% CI = 42%-87%). Patients with M- disease showed a significantly better outcome than M+ patients, with 75% showing PFS at 5 years vs. 45% (p = 0.01).

Conclusion: The overall PFS observed is comparable to that obtained in pediatric series and suggests that a more effective therapy must be developed for high-risk patients.