Radiation treatment for medulloblastoma: a review of 64 cases at a single institute.

BACKGROUND Although the optimal treatment mode for medulloblastoma is frequently discussed, results based on large series of cases, especially those treated in Asia, have rarely been reported. Our purpose was to evaluate the efficacy of postoperative radiation therapy, and to identify prognostic factors, in a relatively large cohort of patients with limited-stage medulloblastoma treated at a single institute in China. METHODS Between January 1996 and April 2001, 69 patients with Chang stage M0/M1 medulloblastoma were referred to our hospital for radiation therapy after total or subtotal resection of the primary tumor. All patients received 30 Gy to the craniospinal axis followed by a 20-25 Gy boost to the posterior fossa (median fraction, 1.8 Gy). RESULTS Sixty-four patients were followed for a median period of 38.5 months. The rates of 3-year and 5-year overall survival were 68.8% and 55.7%, respectively; corresponding disease-free survival were 57.8% and 51.4%, respectively. Patients who had received radiation treatment within 25 days after resection had a greater probability of 3-year survival (81.5% versus 59.5%; P = 0.11) and 3-year disease-free survival (74.1% versus 46.0%; P = 0.03) than patients who began radiation treatment later. No relationship was found between survival and age, sex or tumor size. CONCLUSIONS This regimen was comparatively ineffective in preventing recurrence of postoperative medulloblastoma; however, we found that the interval between surgery and radiation is a significant prognostic factor for disease-free survival.