In 2008, the TCGA published its first results on Glioblastoma multiforme (GBM) in "Nature". These first results published on 91 tumor-normal matched pairs. While 587 biospecimens were collected for the study, most were rejected during quality control: the tumor samples needed to contain at least 80% tumor nuclei and no more than 50% necrosis, and a secondary pathology assessment had to agree that the original diagnosis of GBM was accurate. A last batch of samples were excluded because the DNA or RNA collected was not of sufficient quality or quantity to be analyzed by all of the different platforms used in this study.