Metastasis Stage, Adjuvant Treatment, and Residual Tumor Are Prognostic Factors for Medulloblastoma in Children: Conclusions From the Children's Cancer Group 921 Randomized Phase III Study

VCP plus XRT is a superior adjuvant combination compared with 8-in-1 chemotherapy plus XRT. For patients with M0 tumors, residual tumor bulk (not extent of resection) is a predictor for PFS. Patients with M0 tumors, > or = 3 years with < or = 1.5 cm2 residual tumor, had a 78%+/-6% 5-year PFS rate. Children younger than 3 years old who received a reduced XRT dosage had the lowest survival rate.