PTEN and soft tissue sarcoma: Review of the TCGA database indicates that co-mutation of TP53 and PTEN occurs more frequently (66.7%; n = 21) in UPS as compared to all other soft tissue sarcomas (43.4%; n = 221) (Chi-squared = 28.108, df = 3, p<0.0001), indicating that this combination of mutations is frequently observed in human UPS.