['Tumor risk stratification during diagnosis is paramount for children with medulloblastomas, primarily because very young patients (<3 years) suffer cognitive deficits from radio- and chemotherapy sequelae. Thus, distinguishing tumors that are biologically more aggressive is essential for medulloblastoma management to maximize the delay in radiation treatment without adversely affecting survival outcome. In this context, current strategies for risk assessment, which are based on clinical parameters, remain unsatisfactory.', 'Array-based comparative genomic hybridization (aCGH) was used to identify chromosomal copy number abnormalities in a cohort of 49 medulloblastoma tumors. Based on the karyotypes generated from aCGH analysis, each tumor was scored for copy number abnormalities, and the log-rank test was used to evaluate whether any cytogenetic events were associated with survival.', 'A single copy gain of 1q was shown to be a negative prognostic marker for survival in medulloblastomas with high statistical significance (P < 0.0001, log-rank test).'] Is gain of 1q a potential univariate negative prognostic marker for survival in medulloblastoma?