This is consistent with our additional finding that all patients with a RB1 deletion or mutation did not harbor a CDKN2A deletion/mutation or CDK4 amplification and that all patients with a CDKN2A deletion/mutation or CDK4 amplification did not harbor a RB1 deletion/mutation, suggesting that the genomic alterations in these two pathways are mutually exclusive, consistent with the previous study on Rb1 pathway alteration in 31 tumor types using The Cancer Genome Atlas (TCGA) database [34]. This evidence concerns the gene CDK4 and neoplasm.