TP53 and cancer: For comparison, mutation of the tumor suppressor gene TP53 is the most prevalent alteration identified within The Cancer Genome Atlas (TCGA) dataset, at 37%.18 The next 23 most common alterations observed in TCGA tumors are chromosome arm aneuploidies.13 The most common of these chromosome arm alterations include the gains of 20q (31.9%), 7p (31%), 8q (29.6%), 1q (27.8%), 7q (27.3%), and 20p (26.4%), and the loss of 17p (24.6%).13 These frequencies are comparable to those measured in other cancer data sets.3,4,19,20